Until 20 April 1994:
National Industrial Chemicals Notification and
Assessment Scheme
Chrysotile Asbestos
Priority Existing Chemical No. 9
_________________________________________
Full Public Report
February 1999
i
Chrysotile Asbestos
?Commonwealth of Australia 1999
ISBN 0-642-37402-3
This work is copyright. Apart from any use as permitted under the Copyright Act 1968,
no part may be reproduced by any process without prior written permission from the
Commonwealth available from the Department of Communications, Information
Technology and the Arts. Requests and inquiries concerning reproduction and rights
should be addressed to the Commonwealth Copyright Administration, Intellectual
Property Branch, Department of Communications, Information Technology and the Arts,
GPO Box 2154, Canberra ACT 2601 or posted at http://www.dcita.gov.au/cca .
ii Priority Existing Chemical Number 9
Preface
This assessment was carried out under the National Industrial Chemicals Notification and
Assessment Scheme (NICNAS). This Scheme was established by the Industrial
Chemicals (Notification and Assessment) Act 1989 (the Act), which came into operation
on 17 July 1990.
The principal aim of NICNAS is to aid in the protection of people at work, the public and
the environment from the harmful effects of industrial chemicals, by assessing the risks
associated with these chemicals.
NICNAS is administered by the National Occupational Health and Safety Commission
(NOHSC) and assessments are carried out in conjunction with Environment Australia
(EA) and the Therapeutic Goods Administration (TGA), who carry out the environmental
and public health assessments, respectively. NICNAS has two major programs: one
focusing on the risks associated with new chemicals prior to importation or manufacture;
and the other focussing on existing chemicals already in use in Australia.
As there are many thousands of existing industrial chemicals in use in Australia, NICNAS
has an established mechanism for prioritising and assessing these chemicals. Such
chemicals are referred to as Priority Existing Chemicals (PECs).
The scope of the PEC assessment is to establish the risks to workers, members of the
public and the environment from importing, manufacturing, using, storing, handling and
disposal of a chemical in Australia. This permits recommendations to be made which will
assist in the management and/or further evaluation of such risks. Recommendations may
be specifically directed at industry (employers and employees), union bodies and Federal
and State/Territory regulatory authorities or may be of a more generic nature, such as
those identifying further research needs. NICNAS is a national scientific assessment
scheme and cannot make regulatory decisions which fall within the responsibility of the
State/Territories or other Commonwealth authorities. Recommendations can only be
given effect through consideration of risk management practices and processes by those
agencies/authorities charged with regulatory decision making.
This Full Public PEC report has been prepared by the Director (Chemicals Notification
and Assessment) in accordance with the Act. During all stages of preparation, the report
has been subject to internal peer review by NICNAS, NOHSC, Environment Australia
and Therapeutic Goods Administration. Specific sections of this report were also peer
reviewed by WorkCover, New South Wales; University of Sydney, Department of Public
Health and Community Medicine and US EPA Office of Prevention, Pesticides and Toxic
Substances (Risk Assessment Division).
Under Sections 60D and 60E of the Act, applicants were provided with a draft copy of the
report for correction of errors and variation (for a period of 56 days). The corrected draft
was also available for public comment on 6 October 1998 (as notified in the October 1998
edition of the Commonwealth Chemical Gazette and the Weekend Australian on 10/11
October 1998) for a period of 28 days. Over 150 draft reports were requested during this
period and 17 formal requests for variation were received. The Director's decision
(concerning each request) was made available to each respondant and to other interested
iii
Chrysotile Asbestos
parties (for a period of 28 days) by way of notice in the December 1998 edition of the
Commonwealth Chemical Gazette.
In accordance with Section 62 of the Act, publication of this report revokes the
declaration of chrysotile (white asbestos) as a PEC. However, notwithstanding current
State/Territory regulations regarding the use of chrysotile, an introducer of chrysotile
must inform the Director (under Section 64(2) of the Act) of any new circumstances that
may require a further assessment of risks to human health and the environment. For
further details refer to Section 14 (Secondary Notification) of this report.
For the purposes of Section 78(1) of the Act, copies of Full Public Reports for New and
Existing Chemical assessments may be inspected by the public at the Library, Worksafe
Australia, 92-94 Parramatta Road, Camperdown, Sydney, NSW 2050 (between 10 am and
12 noon and 2 pm and 4 pm each weekday). Summary Reports are published in the
Commonwealth Chemical Gazette, which are also available to the public at the above
address.
Copies of this and other PEC reports can also be purchased from NICNAS either by using
the prescribed application form at Appendix 10 of this report, or directly from the
following address:
GPO Box 58
Sydney
NSW 2001
AUSTRALIA
Tel: +61 (02) 9577 9437
Fax: +61 (02) 9577 9465 or +61 (02) 9577 9465 9244
Other information about NICNAS (also available on request) includes:
? NICNAS Service Charter;
? information sheets on NICNAS Company Registration;
? information sheets on PEC and New Chemical assessment programs;
? application forms for chemical assessment;
? subscription details for the NICNAS Handbook for Notifiers; and
? subscription details for the Commonwealth Chemical Gazette.
Information on NICNAS, together with other information on the management of
workplace chemicals can be found on the NOHSC Web site:
http://www.worksafe.gov.au/worksafe/03/030000.htm
iv Priority Existing Chemical Number 9
Contents
Preface iii
Abbreviations and Acronyms xii
1. Introduction 1
1.1 Declaration 1
1.2 Objectives 1
1.3 Scope of the assessment 1
1.4 Sources of information 2
2. Background 3
2.1 Classification of asbestiform materials 3
2.2 Trends in asbestos use worldwide 4
2.3 Trends in asbestos use in Australia 5
3. Chemical and Physical Properties 6
3.1 Chemical name 6
3.2 Other names 6
3.3 Trade names 6
3.4 Molecular formula and structure 7
3.5 Molecular weight 7
3.6 Chemical composition 7
3.7 Impurities 7
3.8 Physical properties 8
3.8.1 Solubility 8
3.8.2 Thermal degradation 9
4. Methods of Detection and Analysis 10
4.1 Qualitative analysis 10
4.2 Determination of asbestos in air 10
4.2.1 Membrane filter method (using phase
contrast microscopy) 10
4.2.2 Transmission electron microscopy (TEM) 11
4.2.3 Scanning electron microscopy (SEM) 12
4.3 Comparison of methods 13
v
Chrysotile Asbestos
5. Manufacture and Use 14
5.1 Historical overview of importation and mining of chrysotile
in Australia 14
5.2 Current importation of chrysotile and asbestos products
in Australia 14
5.2.1 Australian Customs data 14
Imports of raw chrysotile 16
5.2.2
5.2.3 Imports of chrysotile/asbestos products 17
5.3 Current manufacture of chrysotile products 20
5.3.1 Bendix Mintex Pty Ltd 20
5.3.2 Richard Klinger Pty Ltd 21
5.3.3 Vivacity Engineering Pty Ltd 21
5.4 NICNAS surveys on the use of chrysotile products 21
5.4.1 Automotive industry 21
5.4.2 Aircraft industry 21
5.4.3 Industrial equipment and machinery 25
5.5 Current exports of asbestos and asbestos products 25
5.6 Summary
6. Occupational Exposure 29
6.1 Exposure to chrysotile during Australian manufacturing
Processes 29
6.1.1 Manufacture of friction materials 29
6.1.2 Manufacture of compressed asbestos fibre sheeting
(CAF) and gaskets 32
6.1.3 Manufacture of epoxy resin adhesive 38
6.2 Exposure during end-use in Australian industries 38
6.2.1 End-use monitoring data 39
6.3 International exposure/monitoring data 47
6.3.1 Manufacture of asbestos products 47
6.3.2 Exposure to asbestos in end-use products 47
6.4 Summary 53
7. Health Effects and Risk Characterisation 57
7.1 Historical overview 57
7.1.1 Classification of health effects 57
7.2 Human health effects from exposure to asbestos 58
7.2.1 Asbestosis 58
7.2.2 Lung cancer 58
7.2.3 Mesothelioma 59
7.2.4 Other malignancies 61
vi Priority Existing Chemical Number 9
7.3 Human health effects from exposure to chrysotile 61
7.3.1 Asbestosis 62
7.3.2 Lung cancer 62
7.3.3 Mesothelioma 64
7.3.4 Epidemiological studies on friction product manufacture 65
7.3.5 Case reports of mesothelioma in car mechanics 66
7.4 Animal data 66
7.5 The relationship between fibre type and size
to carcinogenicity 67
7.6 Characterisation of lung cancer risk from asbestos exposure 68
7.6.1 Risks in the friction product industry 69
7.6.2 Uncertainties in chrysotile risk estimates 70
7.7 Conclusions 72
8. Public Health Assessment 73
8.1 Public exposure 73
8.1.1 Manufacture 73
8.1.2 End-use 73
8.1.3 Transport and storage 74
8.1.4 Disposal 74
8.2 Public health risks 74
8.3 Conclusions 76
9. Environmental Assessment 77
9.1 Environmental fate and exposure 77
9.1.1 Release from manufacture 77
9.1.2 Release from end uses 78
9.1.3 Fate 78
9.2 Environmental effects 79
9.3 Environmental risk assessment 80
9.4 Conclusions 81
10. Risk Management 82
10.1 Regulation of asbestos in Australia 83
10.1.1 Workplace regulation 83
10.1.2 Transportation regulation 95
10.1.3 Environmental regulation 95
10.1.4 Details of regulation in Australia 96
10.2 International and overseas regulation of asbestos 100
10.2.1 International initiatives 100
10.2.2 Country specific regulations 102
vii
Chrysotile Asbestos
10.3 Compliance issues 108
11. Asbestos Alternatives 110
11.1 Background 110
11.2 Use of alternatives overseas 110
11.3 Use of alternatives in Australia 110
11.4 Friction material alternatives 111
11.4.1 Road safety issues associated with replacement of
chrysotile with non-asbestos materials in friction products 115
11.4.2 Use of alternative materials in friction products
in Australia 115
11.5 Safety assurance/regulation of friction products 118
11.5.1 New vehicle market 118
11.5.2 Vehicle aftermarket 118
11.5.3 General safety and other issues of aging car fleet 119
11.6 Gaskets material alternatives 120
11.6.1 Use of alternative materials in gaskets in Australia 122
11.7 Health effects of alternative materials 125
12. Secondary Notification 131
13. Discussion and Conclusions 132
13.1 Scope of the assessment 132
13.2 Current use in Australia 132
13.3 Effects of concern 133
13.4 Exposures arising from current use 134
13.4.1 Occupational 134
13.4.2 Public 135
13.4.3 Environment 135
13.5 Current regulation and risk management 136
13.5.1 Australia 136
13.5.2 Overseas 137
13.6 Alternatives 137
14. Recommendations 139
14.1 Preamble 139
14.2 Recommendations 140
viii Priority Existing Chemical Number 9
APPENDICES
Appendix 1 List of applicants 145
Appendix 2 Sources of information 146
Appendix 3 Analysis of 1994 Australian customs data on asbestos
and asbestos products 151
Appendix 4 Summary of information received in response to survey
of importers of asbestos products 155
Appendix 5 List of companies involved in the `new vehicle manufacturing
and importing survey' 159
Appendix 6 Sample Material Safety Data Sheet for chrysotile (white asbestos) 160
Appendix 7 Asbestos bans/restrictions in specific countries 165
Appendix 8 Export data on certain products which contain
(or may contain) asbestos 184
Appendix 9 Studies on the relationship of age to safety of the Australian
car fleet 185
REFERENCES 186
ORDER FORM FOR NICNAS PRODUCTS 199
LIST OF TABLES
Table 1 US demand pattern
Table 2 Physical properties
Table 3 Importation of asbestos and non-asbestos brake linings and asbestos
gaskets for the period 1994-1998
Table 4 Use of asbestos parts in aircraft (NICNAS Survey 1994)
Table 5 Number of workers and duration and frequency of exposure
Table 6 Personal air monitoring data for airborne fibres (1992 to 1997) at Bendix
Mintex plant
Table 7 Worker exposure at Perth and Melbourne sites
Table 8 Asbestos air monitoring data (1989-1996) at Richard Klinger
(Melbourne plant)
Table 9 Asbestos air monitoring data (1991-1996) at Richard Klinger
(Perth plant)
Table 10 Worker exposure to asbestos by work practice ?NICNAS Automotive
Aftermarket Survey
Table 11 Personal and static monitoring results using MFM ?br>
NICNAS Automotive
Table 12 TEM fibre types and fibre counts ?NICNAS Automotive
Aftermarket Survey
Table 13 Monitoring results for service garages, Western Australia
Table 14 Air monitoring results during processing of asbestos gaskets
Table 15 Atmospheric monitoring data for overseas manufacturing sites
ix
Chrysotile Asbestos
Table 16 Overseas monitoring data for atmospheric levels of
asbestos in garage
workshops
Table 17 Exposure during gasket removal and installation
Table 18 Summary of epidemiological cohort studies of workers
exposed predominantly to chrysotile
Table 19 Lung cancer risk by industry segment and fibre type
Table 20 Estimates of lung cancer risk from exposure to chrysotile
in different industries
Table 21 Estimated risk of lung cancer at various levels of
exposure to chrysotile
Table 22 Status of implementation in Australian jurisdictions of
NOHSC Standards and Codes relevant to asbestos/chrysotile
Table 23 Comparison of information contained on labels supplied
for chrysotile friction products and gaskets with information
recommended by NOHSC
Table 24 Current Australian State and Territory exposure
standards for chrysotile
Table 25 Main legislative instruments in Australian States and
Territories for the control of asbestos
Table 26 Prohibitions (absolute) on asbestos use in Australia
Table 27 Current status of prohibition of asbestos-containing
friction materials and gaskets (by country)
Table 28 International exposure limits for chrysotile
Table 29 Composition of alternative (non-asbestos) friction materials and uses
Table 30 Advantages and disadvantages of some non-asbestos
alternatives in friction products
Table 31 Introduction of non-asbestos components by top 10 companies
in Australia
Table 32 Properties of asbestos and some alternatives for use in gaskets
Table 33 Advantages and disadvantages of alternative materials
used for gaskets according to Richard Klinger Pty Ltd
Table 34 Alternatives for gaskets in use in Australia
Table 35 Dimensions of asbestos fibres and alternatives
(non-asbestiform) materials
Table 36 Health effects of alternative materials used in friction products
and gaskets
LIST OF FIGURES
Fig 1 Production and importation of chrysotile in Australia, 1890 to 1990
Fig 1A Customs data for import of raw chrysotile during 1997
Fig 1B Customs data for import of fibre cement products during 1997
Fig 1C Customs data for import of "other" products containing
asbestos (including gaskets) during 1997
Fig 1D Customs data for import of friction materials during 1997
x Priority Existing Chemical Number 9
Fig 2 Australian importation of raw chrysotile, 1982 to 1996
Fig 3 Age of vehicles in Australia in 1995
Fig 4 Proportion of cars older than 10 years in 1995
Fig 5 Asbestos air (personal) monitoring data 1992-1996,
Richard Klinger Pty Ltd, Perth site
Fig 6 Incident cases of malignant mesothelioma in Australia 1945-1996
xi
Chrysotile Asbestos
Abbreviations and Acronyms
ABS Australian Bureau of Statistics
ACGIH American Conference of Governmental Industrial Hygienists
ACS Australian Customs Service
ADG Australian Dangerous Goods
ADR Australian Design Rule
AICS Australian Inventory of Chemical Substances
ASME American Society of Mechanical Engineers
CAF compressed asbestos fibre
CAS Chemical Abstracts Service
CF compressed fibre
CSIRO Commonwealth Scientific and Industrial Research Organisation
EC European Commission
EINECS European Inventory of Existing Commercial Chemical
Substances
EA Environment Australia
EEC European Economic Community
EU European Union
f/mL fibres per millilitre of air
FORS Federal Office of Road Safety (Australian)
HSE Health and Safety Executive (UK)
IARC International Agency for Research on Cancer
ILO International Labour Organisation
INSERM Institute de la Santa et de la Recherche Medicale
IPCS International Programme on Chemical Safety
ISO International Organization for Standardization
i.p. intraperitoneal
LD lethal dose
median lethal dose
LD50
LOAEL lowest observed adverse effect level
MFM membrane filter method
MFM/PCM membrane filter method using phase contrast microscopy
MLD minimum lethal dose
xii Priority Existing Chemical Number 9
MOS margin of safety
mpcf millions of particles per cubic foot
MS mass spectrometry
MSDS material safety data sheet
NAO non-asbestos organic
NICNAS National Industrial Chemicals Notification and Assessment
Scheme
NOAEL no observed adverse effect level
NOHSC National Occupational Health and Safety Commission
OECD Organisation for Economic Cooperation and Development
OSHA Occupational Safety and Health Administration (USA)
PAN Polyacrylonitrile
PCM phase contrast light microscopy
PEC predicted environmental concentration
PEC Priority Existing Chemical
PNEC predicted no effect concentration
PPE personal protective equipment
PTFE polytetrafluoroethylene
PVA Polyvinylalcohol
PVC polyvinylchloride
RCF refractory ceramic fibres
RTECS Registry of Toxic Effects of Chemical Substances
SAED selected area electron diffraction
SCBA self contained breathing apparatus
SEM scanning electron microscopy
SMF synthetic mineral fibres
SMR standard mortality ratio
STEL short term exposure limit
SUSDP Standard for the Uniform Scheduling of Drugs and Poisons
TEM transmission electron microscopy
TGA Therapeutic Goods Administration
TSCA Toxic Substances and Control Act (USA)
TWA time weighted average
祄 micrometre
UN United Nations
US EPA United States Environmental Protection Agency
xiii
Chrysotile Asbestos
xiv Priority Existing Chemical Number 9
1. Introduction
1.1 Declaration
Chrysotile (CAS No. 12001-29-5) was declared by the Minister for Industrial
Relations as a PEC under the Industrial Chemicals (Notification and Assessment)
Act 1989 (Cwlth) (the Act) by notice in the Chemical Gazette of 7 November
1995. In accordance with the Act, importers of `raw' chrysotile applied for the
assessment of the chemical as a PEC. Suppliers/importers of chrysotile
`products/articles' were not required to apply for assessment, but were required to
provide relevant information/data. Appendix 1 provides details of applicants.
The declaration was made on the basis that:
? chrysotile is a known human carcinogen;
? there is continued widespread use of chrysotile in Australia;
? the major uses of chrysotile are in the automotive industry in friction products
and in gaskets and, therefore, there is potential for occupational exposure
during distribution and handling, manufacture, aftermarket processing (e.g.,
machining, fitting) and use of chrysotile products; and
? public and environmental exposure to chrysotile may occur during use and
disposal.
1.2 Objectives
The objectives of this assessment were to:
? assess the occupational, public health and environmental risks associated with
current uses and applications in Australian industry;
? characterise current and future uses of chrysotile asbestos in Australia and to
compare the situation with overseas countries;
? assess the feasibility of substitution of chrysotile materials and voluntary
and/or legislative action for reducing potential health and safety risks arising
from manufacture and import of chrysotile and chrysotile products.
? to provide recommendations for a risk reduction strategy for chrysotile based
on the assessment of available information.
1.3 Scope of the assessment
Consistent with the objectives, this report considers all relevant information
relating to exposure to chrysotile from import of raw chrysotile and asbestos-
containing products and manufacture of chrysotile products. Chrysotile products
already in place in the community are outside the scope of this report.
With regard to health effects associated with exposure to chrysotile, reviews were
used as the main source of data, due to the fact that the health effects of chrysotile
have been extensively studied and understood. Similarly, an `in-depth' evaluation
1
Chrysotile Asbestos
of chrysotile alternatives was outside of the scope of this report and therefore
international reviews were evaluated in preference to original studies.
1.4 Sources of information
Information for the different sections of the PEC assessment report required in-
depth and thorough investigations through various data sources and mechanisms.
These data sources and the way they were utilised are detailed in Appendix 2.
The various sources of information that were used for this assessment report
included:
? Data from the Australian Bureau of Statistics (ABS) and Australian Customs
Service (ACS) on import and export volumes of asbestos and asbestos
products;
? Data supplied by importers (applicants) of raw chrysotile;
? Three surveys on companies importing chrysotile products, companies
importing and manufacturing new vehicles and companies involved in the
aftermarket use of chrysotile products;
? Exposure data obtained from a monitoring study carried out by NOHSC; and
? Consultants report on international/national regulations on asbestos.
Other sources of information include database and literature searches and
information obtained from national and overseas regulatory agencies and other
relevant institutions.
2 Priority Existing Chemical Number 9
2. Background
2.1 Classification of asbestiform materials
Asbestos is defined as the fibrous form of mineral silicates belonging to the
serpentine and amphibole groups of rock-forming minerals. The most common
asbestos types are chrysotile (white asbestos) a fibrous serpentine mineral and
amosite (brown asbestos) and crocidolite (blue asbestos) which are amphiboles.
Other forms of amphibole asbestos include actinolite, anthophyllite and tremolite.
ASBESTOS MINERALS
Asbestos
Fibrous serpentine Fibrous amphiboles
Amosite Actinolite
(brown asbestos Tremolite
Chrysotile
(white asbestos)
Crocidolite
Anthophyllite
(blue asbestos)
Asbestos has been used in a variety of capacities for centuries in many countries.
Asbestos, including chrysotile, has been used in many applications because of its
reinforcement, thermal (and electrical) insulation, and heat resistance properties.
Some applications of asbestos only utilise one of these properties whereas other
applications require several properties. Asbestos has also been used in yarns and
textiles due to its flexibility and strength. It is elastically compressible, and
therefore, suitable for use in packings, jointings and seals.
In the past, Australia has mined and imported asbestos fibre. Asbestos fibre was
used to manufacture asbestos products, such as asbestos cement articles, asbestos
yarn cord and fabric, asbestos joint and millboard, asbestos friction materials and
gaskets. These products were also imported into Australia as finished articles.
Asbestos mining (crocidolite and chrysotile) ceased altogether in Australia in
1983.
3
Chrysotile Asbestos
2.2 Trends in asbestos use worldwide
Although significant amounts of amphibole asbestos were used in the past,
chrysotile is the major type used in the world today, with amphiboles comprising
less that 3% of total asbestos usage. Countries that account for the majority of
the world production of chrysotile are Brazil, Canada, China, Kazakhstan, Russia,
South Africa and Zimbabwe (Pigg, 1994; Lemen & Bingham, 1994).
Lemen & Bingham (1994) reported that world production and consumption of
asbestos peaked in 1976 and declined only slightly during the early 1980s. World
production was 4.5 million tons in 1985, dropped to 4.2 million tons in 1988, and
was projected to be 4.4 million tons in 1990.
Some of the commercial applications for asbestos in the world today (Lemen &
Bingham, 1994) are:
Asbestos cement products 70%
Vinyl asbestos flooring 10%
Friction products 7%
Asbestos paper & felt 5%
Gaskets & packings 3%
Paints, roof coatings, caulks, etc 2%
Filter media 2%
Asbestos textile products 1%
All other uses < 1%
Over the last few years, asbestos consumption has declined worldwide, especially
in North America and European markets. For example in the United States
during the period of 1977-1991, there has been a large decline in asbestos use.
This decline is shown in Table 1.
Table 1 - US demand pattern (x 103 tonnes)
Product 1977 1991
Asbestos-cement pipe 115 4
Asbestos-cement sheet 27 2
Coating and compounds 36 1
Flooring products 150 -
Friction products 57 10
Installation: electrical 4 1
Installation: thermal 17 -
Packing and gaskets 28 3
Paper products 7 -
Plastics 8 -
Roofing products 70 15
Textiles 10 -
Other 143 1
Total* 672 34
(Adapted from Pigg,1994)
*Data does not add up to totals shown because of independent rounding.
4 Priority Existing Chemical Number 9
Use of asbestos is increasing in some countries. For example asbestos-cement
production continues to grow in South America, Southeast Asia, the Middle East
and Eastern Europe. Japan, Thailand, Malaysia, Korea and Taiwan imported
430,000 tonnes in 1989, that is, well over 30% of worldwide asbestos (Pigg,
1994). In developing countries the principle use of asbestos is as building
material for dwellings and potable water piping.
2.3 Trends in asbestos use in Australia
Chrysotile was mined in Australia for over 100 years with production gradually
increasing until cessation in 1983. The main Australian centres of asbestos
mining were the crocidolite deposits of the Hamersley Ranges in Western
Australia, and chrysotile deposits at Baryulgil and Woods Reef in New South
Wales, and Lionel and Nunyerrie in Western Australia (Commonwealth of
Australia - Department of National Development Bureau of Mineral Resources,
1965).
Amosite has never been mined in Australia (Hughes, 1977).
Crocidolite dominated asbestos production until the closure of the Wittenoom
mine in 1966. The highest and final quantity of crocidolite production was
between1960-1969 and was 86,566 tonnes.
In Australia the mining of chrysotile peaked during the 1970s in which period a
total of 400,000 tonnes was produced. Mining of chrysotile ceased in 1983, at
which time approximately 55,000 tonnes per year of chrysotile was being
produced in Australia and approximately 20,000 tonnes imported. The
importation of chrysotile has dropped significantly since this period to
approximately 2000 tonnes per annum.
Raw chrysotile continues to be imported into Australia. Articles also containing
chrysotile are both locally produced and imported. The raw chrysotile is used for
the manufacture of friction materials such as brake disc pads, brake linings and
brake blocks and in the manufacture of gaskets. Gaskets are widely used in the
industrial sector for high temperature and pressure applications. Similar
chrysotile products are also imported.
There are many asbestos products that were used in the past that are still present
in the community. These are known as fixed uses. Areas where fixed use of
asbestos may be found are insulation, cement materials (pipe and building
materials), vinyl floor tiles and sealants.
Asbestos use is extensively regulated in Australia. However, in each jurisdiction
more severe restrictions exist in relation to particular forms of asbestos other than
chrysotile (generally amosite and crocidolite). This is discussed further in
Section 10 (Risk Management).
5
Chrysotile Asbestos
3. Chemical and Physical
Properties
3.1 Chemical name
Chrysotile is listed on the Australian Inventory of Chemical Substances (AICS).
CAS number 12001-29-5
EC number 650-013-00-6
RTECS number GC2625000
3.2 Other names
Asbestos
Serpentine asbestos
White asbestos
3.3 Trade names
7-45 Asbestos
Avibest
Avibest C
Calidria RG 100
Calidria RG 144
Calidria RG 600
Cassiar AK
K 6-30
NCI C61223A
5RO4
3.4 Molecular formula and structure
Molecular formula: Mg3Si2O5(OH)4
The crystal structure of chrysotile is layered or sheeted similarly to the kaolinite
group. It is based on an infinite silica sheet (Si2O5) in which all the silica
tetrahedra point one way. On one side of the sheet structure, and joining the
silica tetrahedra, is a layer of brucite, Mg(OH)2. The result is a layered structure.
6 Priority Existing Chemical Number 9
3.5 Molecular weight
283
3.6 Chemical composition
Chemical analysis shows that chrysotile typically consists of the following range
of major constituents (%) (IPCS, 1986):
38 - 42
SiO2
MgO 38 - 42
N2O+ 11.5 - 13
Fe2O3 0-5
FeO 0-3
Al2O3 0-2
CaO 0-2
Na2O 0-1
3.7 Impurities
Impurities that are present in chrysotile may be part of the crystal structure or due
to associated minerals. The most common impurities are iron and aluminium.
Other impurities associated with chrysotile in lesser amounts are calcium,
chromium, nickel, manganese, sodium and potassium.
Common mineral impurities found in commercial grades of chrysotile from
various locations include magnetite, chromite, brucite, calcite, dolomite and
awaruite. Within the chrysotile lattice, nickel and iron can occur as minor
isomorphic substitutions for magnesium.
Chrysotile is frequently contaminated by small amounts of other fibrous minerals
such as tremolite (HSDB, 1998).
7
Chrysotile Asbestos
3.8 Physical properties
Chrysotile is an odourless white, grey, green, yellowish fibrous (flexible) solid
material with a soft, `soapy' texture at standard temperature and pressure (HSDB,
1998).
Table 2 - Physical properties
Property Value Reference
Boiling point Not applicable
Melting point/decomposition (US Department Of Health
800-850篊
temperature & Human Services, 1995)
Tensile strength 31,000kg/sq cm HSDB (1998)
Specific gravity 2.55 HSDB (1998)
Vapour pressure Not applicable, expected to be low
Partition coefficient Not applicable in view of expected
insolubility of this inorganic
compound in octanol.
Isoelectric point 11.8 (US Department Of Health
& Human Services, 1995)
Approximately 10 (in aqueous
pH (Budavari et al., 1989)
slurry)
Electrical charge at neutral pH* Positive (US Department Of Health
& Human Services, 1995)
Flammability limits Non-flammable (US Department Of Health
& Human Services, 1995)
*
Chrysotile is isoelectric (zero charge) over the pH range 10.0 to 12.0, and tends to have a positive
charge at physiological pH.
3.8.1 Solubility
Chrysotile is insoluble in water (pH 7) and organic solvents. The solubility of
chrysotile is both pH and temperature dependent, for example acidic conditions
and high temperatures will cause chrysotile fibres to dissolve rapidly (Schreir,
1989). While other forms of asbestos fibres are stated as fairly resistant to acids,
chrysotile is described as soluble in acid (Kirk-Othmer, 1985), with a 56.0%
weight loss (due to loss of counter-ions; silicate structure remains intact).
However, only around 1% dissolution is seen under basic conditions (US
Department Of Health & Human Services, 1995).
Solubility under acidic conditions is to be expected from the chemical structure of
chrysotile. Serpentine chrysotile has a structure composed of layers of silicate
tetrahedrons linked into sheets. Between the silicate layers are layers of
magnesium hydroxide (brucite layers). In most serpentines, the silicate and
brucite layers are more mixed and produce convoluted sheets. In the asbestos
varieties, the brucite and silicate layers bend into tubes that produce the fibres
(Amethyst Galleries Inc., 1996a). Magnesium hydroxide is practically insoluble
in water, but is soluble in dilute acids (Budavari et al., 1989).
8 Priority Existing Chemical Number 9
3.8.2 Thermal degradation
Chrysotile is subject to thermal decomposition at elevated temperatures. This
thermal decomposition is a two stage reaction consisting first of a
dehydroxylation phase and then a structure phase change. Dehydroxylation or
the loss of water occurs at 600-780篊. At 800-850篊 (see Table 2) the
anhydride breaks down to forsterite* and silica. These reactions are irreversible
(HSDB, 1998).
*Forsterite is a member of the olivine series of iron magnesium silicates, and is non-fibrous. It is
magnesium rich with a formula approximating Mg2SiO4 (Amethyst Galleries Inc, 1996).
9
Chrysotile Asbestos
4. Methods of Detection and
Analysis
4.1 Qualitative analysis
Several methods are available, either singly or in combination, for the qualitative
analysis of asbestos. For specificity in identification of asbestos minerals, the
ranking is electron microscopy, optical microscopy, X-ray diffraction and infra-
red spectophotometry.
4.2 Determination of asbestos in air
The determination of asbestos (including chrysotile) in air entails two steps,
sampling and analysis. Sampling typically involves drawing a measured volume
of air through a filter mounted in a holder. When sampling for occupational
exposure, the holder is located in the breathing zone (personal sampler) of the
worker. Static sampling involves taking samples at fixed locations and provides
information on asbestos concentrations in the general area. Asbestos fibres are
collected on the filter which is removed for analysis at the end of the sampling
period.
Analytical methods usually determine the fibre number concentration of asbestos
in air. Some analytical methods also enable characterisation of the fibres. The
standard analytical method for counting fibres is the membrane filter method
using phase contrast light microscopy (PCM). Electron microscopy techniques,
scanning electron microscopy (SEM) and transmission electron microscopy
(TEM), have also been used for counting, especially for low fibre concentrations
and environmental sampling. Accessories to the electron microscope such as
Selected Area Electron Diffraction (SAED) and Spectrum Analysis (EDXA) have
further enabled identification of fibres.
4.2.1 Membrane filter method (using phase contrast microscopy)
The membrane filter method using phase contrast microscopy (MFM/PCM) has
been used for many years, both internationally and in Australia, as the standard
method for the determination of asbestos in air in the occupational environment.
Although the methodology may vary slightly between the various published
methods and between testing authorities, the basic principles are similar.
In Australia, the National Occupational Health and Safety Commission (NOHSC)
has published the Guidance Note on the Membrane Filter Method for Estimating
Airborne Asbestos Dust (MFM Guidance Note) in: Asbestos: Code of Practice
and Guidance Notes (NOHSC, 1988). The methodology is generally referred to
as the MFM method and is used as the standard for regulatory monitoring in
Australia. Laboratory accreditation for this method is provided by the National
Association of Testing Authorities (NATA).
10 Priority Existing Chemical Number 9
In the MFM method, air is drawn via a sampling pump through an opaque
membrane filter (mixed esters of cellulose or cellulose nitrate), which is later
transformed into a transparent, optically homogeneous specimen. The fibres
collected on the filter are then sized and counted using a phase contrast
microscope and eyepiece graticule. For the purposes of determination of asbestos
in air by the MFM method, a fibre is defined as having a length greater than 5
祄, a width less than 3 祄, and a length/width ratio greater than 3:1. The result
is expressed as fibres per millilitre of air (f/mL), calculated from the number of
fibres on the filter and the volume of air sampled. For occupational exposures,
results are determined as a time-weighted average (TWA) with sampling over a
4-hour minimum period for comparison to the occupational exposure standard.
The main advantage of the MFM method is it is relatively quick and inexpensive.
Although used as the standard method, it has several limitations (mainly
associated fibre counting of fibres rather than sampling), which are discussed
further in the MFM Guidance Note and highlighted by several authors (Corn,
1994; Lippmann, 1994; Kohyama & Kurimori, 1996). Limitations include:
? the method is not fibre specific and cannot discriminate between the various
types of asbestos, or between asbestos and other types of fibres, e.g., wool,
cotton, cellulose and fibre glass;
? the method has limited resolution and cannot detect very thin fibres (lower
limit of optical resolution for PCM is 0.2-0.3 祄), and it may be difficult to
quantify fibre size;
? artifact "fibres" sometimes form on the filters during mounting for
microscopy, which may give rise to false (high) readings if not recognised.
These limitations may lead to problems such as high background counts and
inaccurate results due to the failure to detect artifacts or some smaller airborne
respirable fibres. In dusty occupations background dust levels may be high and
sampling times may need to be reduced to minimise the particulate or fibre load
on the filter, so consecutive samples must be taken to make up the required
sampling time in order to increase the limit of detection. Consequently, the
method is most useful for analysis of samples that contain a significant amount of
asbestos and where there is not a significant fraction of fibres that are too fine to
be counted.
The NOHSC MFM Guidance Note states that the practical lower detection limit
for occupational sampling is 0.05-0.1 f/mL for a 100 L sample and a minimum
fibre loading of 10 fibres/100 graticule areas (NOHSC, 1988). The limits are
based on the assumption that blank filters contain a few countable fibres. In
practice, the limit of detection may be higher if the conditions above are not met,
for example, lower sample volumes and high blank counts. Suggested changes to
the methodology have been recommended in the NOHSC draft public discussion
paper (proposed National Exposure Standard) on chrysotile (NOHSC, 1995a).
4.2.2 Transmission Electron Microscopy (TEM)
Transmission Electron Microscopy (TEM) has developed as a viable technique
for the determination of asbestos in air. The US National Institute for
Occupational Safety and Health (NIOSH, 1990) Analytical Method 7402 for
asbestos fibres employs TEM which has a detection limit of <0.01 f/mL (in
11
Chrysotile Asbestos
atmospheres free from interference). The latest analytical methodology for
asbestos fibres using TEM is prescribed in ISO Standard 10312 (ISO, 1993). This
method has a detection limit of 0.002 f/mL (in ambient air).
The higher magnification and resolution of the TEM method allow an
examination of shorter and finer asbestos fibres, not permitted by PCM. TEM
equiped with high resolution x-ray spectra (fitted with a tilt and rotate specimen
holder) and selected area electron diffraction patterns (SAED), enables reliable
discrimination between asbestos and non-asbestos fibres and also the ability to
distinguish between different types of asbestos fibres. It has been reported that
TEM can resolve fibres down to 0.02 祄1 in diameter (Kohyama & Kurimori,
1996), which makes it the only viable technique for analysis of chrysotile fibres.
TEM, not only requires considerable capital expenditure, but is time consuming.
In occupational exposure monitoring TEM is only used to confirm results
obtained by MFM/PCM. TEM is the preferred method for monitoring asbestos in
the general environment, where fibre sizes and fibre concentrations are usually
much lower than in occupational situations (Rogers, 1998).
A number of different methods of sample preparation have been used with TEM
and are broadly divided into `direct' and `indirect' transfer methods. The fibres
are basically unaltered in direct transfer methods. With indirect methods, some
mechanical breakdown to smaller fibres often occurs, particularly if sonification
is used (Corn, 1994). As chrysotile fibres are more susceptible to breakdown
through sonification than other asbestos fibres (Breysse, 1991). Due to the
probability of fibre breakdown, results by TEM `indirect' methods are often
quoted in mg/m3 rather than f/mL. Direct TEM methods, such as ISO 10312 are
preferred since they do not change fibre size distributions on the collected sample
(Rogers, 1998).
Attempts have been made to adapt TEM analysis into asbestos removal
guidelines. Due to the considerable analytical variability found at such low fibre
concentrations, TEM monitoring has been found to be impractical and routine
clearance monitoring has reverted to MFM/PCM (Rogers, 1998).
4.2.3 Scanning Electron Microscopy (SEM)
Scanning Electron Microscopy (SEM) permits the sizing of small fibres and with
x-ray spectral attachments most fibres can be identified. The resolution of SEM
is not as good as TEM and is similar to the PCM, such that it is possible to
distinguish non-asbestos fibres and most common types of asbestos down to a
fibre diameter of about 0.2 祄 using x-ray spectral attachments. However, only
the elemental ratio for fibre composition is obtained and this is somewhat
insufficient in positively identifying fibres, as it is often necessary to determine
the internal crystalline structures (National Board of Occupational Safety and
Health, 1982). The principal fibres identified by the SEM are amphiboles such as
amosite, crocidolite and anthophyllite asbestos.
Although there are routine analytical methods using SEM, this method is less
favoured than TEM (in the determination of asbestos fibres in air) due to the
1
Higher resolution (down to 0.005 祄) may be achieved with some contemporary computer
controlled instrumentation.
12 Priority Existing Chemical Number 9
lower analytical resolution and possibility of missidentification of fibres using
this technique (Roberson et al., 1992; AIA, 1984).
4.3. Comparison of methods
Several papers comparing the various methods have been published in the open
literature. Some have compared PCM and TEM (Marconi et al., 1984; Dement &
Wallingford, 1990; Snyder et al., 1987), SEM and TEM (Roberson et al., 1992),
and PCM, SEM and TEM (Cherrie et al., 1989; Kohyama & Kurimori, 1996).
In general, the electron microscopic methods give higher total counts (of fibres >
5 祄 in length) than PCM because the latter cannot detect very thin fibres. In a
comprehensive comparison using similar filter sizes, the total chrysotile fibre
count using TEM by the direct transfer method was approximately four times that
obtained by PCM, with the count for fibres of length > 5 祄 approximately three
times higher (Kohyama & Kurimori, 1996). For the purposes of comparison,
some study authors have advocated the use of multiplication factors which vary
depending on the process to convert results from one method to the other (Snyder
et al., 1987; Cherrie et al., 1989). In the identification of fibres in the comparison
between SEM and TEM (Roberson et al., 1992), TEM was the favoured method
for chrysotile whereas SEM was favoured for amosite. In the NICNAS survey a
good agreement was found between the TEM and PCM methods after adjustment
for differences in fibre size observations (see Section 6.2.1).
The consensus appears to be towards the use of the MFM and PCM for routine
analyses and use of TEM for low level and identification work and situations
where the fibre size and identification are important. The reasons for this
approach are that PCM is simple, cheaper and has been used over a long period
(about 30 years). Most health risk assessments have been based on data derived
from the standard MFM/PCM method. However, with the need to improve the
MFM to detect low fibre concentrations, TEM methods are being used more
widely. Use of TEM or improvement in the MFM would be required to support
any lowering of exposure standards for asbestos below 0.1 f/mL. One possibility
would be to upgrade the MFM/PCM so as to utilise the optimum techniques that
are available in optical microscopy.
13
Chrysotile Asbestos
5. Manufacture and Use
This section covers importation of raw chrysotile; manufacture of chrysotile
products in Australia; importation of chrysotile products and end-use and export
of chrysotile products.
There are numerous types of chrysotile products which were used in the past and
are still present in the general community, which include: asbestos-containing
sprayed insulation materials in buildings and other structures; lagging, asbestos
cement sheets, piping and moulded products in building construction, vinyl
asbestos flooring, sealants, textiles (used in heat resistant clothing), conveyor
belts, boards (marine and soft building boards), felts (roofing), pipe and electrical
coverings and insulating ropes and paper, asbestos yarn for packing, asbestos
gloves and headgear.
Consistent with the objectives of this assessment, use of asbestos is defined as
those uses that are currently being introduced, either by import and/or
manufacture, into Australia. Information on use was collated from data provided
by the Australian Bureau of Statistics (ABS), Australian Customs Service (ACS)
and applicants and from surveys of importers and end-users of chrysotile products
(see Appendices 1 and 2 for details).
5.1 Historical overview of importation and mining of chrysotile in
Australia
Figure 1 shows the production of raw chrysotile in Australia from 1890 to 1983
and for comparison the importation of chrysotile from 1950 to 1983. Mining of
chrysotile peaked dramatically during the 1970s, with new mines such as Wood
Reef mine coming into operation in the early part of the decade. A total of
400,000 tonnes was produced during the 1970s. In 1981 there was a decrease in
the production of chrysotile due to a drop in world demand and the increased
operating costs at the Wood Reef mine. Mining finally ceased in 1983 as the
Wood Reef mine could not meet dust control regulations. At the time mining of
chrysotile ceased (1983), approximately 55,000 tonnes per year was being
produced in Australia and approximately 20,000 tonnes per year of chrysotile was
being imported (Leigh, 1994). Importation of chrysotile has dropped
significantly since this time to approximately 2000 tonnes per annum.
5.2 Current importation of chrysotile and asbestos products
5.2.1 Australian Customs data
Appendix 2 details sources of information and import data for chrysotile, which is
briefly summarised below.
There are four major customs tariff categories, including subcategories, relating
to the importation of asbestos and asbestos products. The customs categories,
product types and quantities imported in 1997 are given in Appendix 3, figures
1A-1D.
14 Priority Existing Chemical Number 9
Figure 1 ?Production and importation of chrysotile in Australia, 1890
to 1990
400000
387500
375000
362500
350000
337500
325000
312500
300000
287500
275000
262500
250000
237500
225000
Quantity (tonnes)
212500
200000
187500
175000
162500
150000
137500
125000
112500
100000
87500
75000
62500
50000
37500
25000 X X
12500
0
1890-1899
1900-1909
1910-1919
1920-1929
1930-1939
1940-1949
1950-1959
1960-1969
1970-1979
1980-1989
NOTE: Production
of chrysotile
Years
ceased in Australia
in 1983
Production of chrysotile
Importation of chrysotile
Chrysotile production did occur between 1890 and 1909, however, the amounts
x were small and therefore not identifiable in the graph.
15
Chrysotile Asbestos
The four customs categories include 1) asbestos (white asbestos and other
asbestos), 2) articles of asbestos-cement, of cellulose fibre-cement or the like, 3)
asbestos products (including gaskets) other than fibre cement products and
friction materials and articles thereof.
When analysing the Australian Customs data to identify the current uses of
asbestos products, the following issues arose:
? only one subcategory (2524.00.00.01) specifically includes chrysotile;
? no differentiation exists between asbestos and non-asbestos products for
some categories. For example, Customs data did not distinguish between
asbestos and non-asbestos brake pads as they all fell under the category "May
or may not contain asbestos";
? only one subcategory exists for asbestos gaskets with no subcategory for non-
asbestos gaskets;
? most Customs tariff classifications have changed over time and are different
for import and export, making historical comparisons of trends difficult;
? some importers (or their agents) unintentionally misclassify asbestos and
asbestos products.
These findings support those of a 1990 inquiry into usage, substitutes and
alternatives of asbestos in Victoria (Victorian Occupational Health and Safety
Commission, 1990). The inquiry found that the current ACS tariff classification
system makes the collection of reliable data on asbestos imports into Victoria
difficult. The report of the inquiry also commented that there is a need for the
customs requirements to be reviewed so that asbestos imports can be more readily
identified and quantified.
Bendix Mintex have commented that in attempts to use customs data in the past
(to determine market penetration of imports) they found that for certain periods,
the data (in terms of number of articles) were impossible to reconcile with their
estimations (based upon known information on vehicle population and usage of
friction materials per vehicle) of total market size. Bendix Mintex have also
identified errors at the Customs level with regard to the correct
identification/recording of imported articles.
5.2.2 Imports of raw chrysotile
The quantity of raw chrysotile imported into Australia for the period 1982 to
1996 is shown in Figure 2. In the mid 1980s the importation of chrysotile rapidly
declined. In the last decade, the amount of chrysotile imported into Australia has
been relatively constant, between 1000 and 2000 tonnes being imported per
annum.
The customs category for `asbestos' (2524.00.00) contains two subcategories:
chrysotile (white) and `other asbestos' (see Appendix 3, Fig.1A). Customs data
for 1997 showed that approximately 735 tonnes of `other asbestos' was imported
into Australia. If this figure is correct it would be a concern due to prohibitions
existing under State and Territory legislation for other forms of asbestos such as
crocidolite and amosite. However, on further investigations and discussions with
importers in relation to this category for 1994 data, it was found that errors had
occurred in tariff coding and that all of the asbestos imported under this
16 Priority Existing Chemical Number 9
subcategory was chrysotile. It is therefore likely that all asbestos being imported
into Australia is chrysotile, however the ACS has been asked to provide further
data for the 1997 figures so that this can be investigated.
Figure 2 ?Australian importation of raw chrysotile, 1982 to 1996*
16,000
14,000
12,000
Quantity (tonnes)
10,000
8,000
6,000
4,000
2,000
0
1982-83
1983-84
1984-85
1985-86
1986-87
1987-88
1988-89
1989-90
1990-91
1991-92
1992-93
1993-94
1994-95
1995-96
Year
*Data for figure 2 was retrieved from the Australian Bureau of Statistics
Customs data for 1997 indicated that approximately 1500 tonnes of chrysotile
was imported (all sourced from Canada), the majority of which was imported by
Bendix Mintex Pty Ltd and Richard Klinger Pty Ltd with Vivacity Engineering
importing much smaller amounts (approximately 16 tonnes/year). These
companies have also stated that they imported similar amounts in 1994, 1995 and
1996. Vivacity Engineering stated that they intended phasing out use of
chrysotile during 1997, however phase out had not been achieved when last
contacted in August 1998.
Current use of raw chrysotile is therefore between 1-2 thousand tonnes per year
and would seem to show no sign of declining in the immediate future although
work is proceeding for alternatives to chrysotile in some industry sectors (see
Section 11 on Asbestos Alternatives). Bendix Mintex have estimated that their
use of chrysotile (as percentage of total sales) will decrease by about 5% per
annum over the next 5 years.
5.2.3 Imports of chrysotile/asbestos products
ABS data for 1997 indicates that chrysotile is imported in a wide range and high
number of products. The ABS data show that the most highly imported asbestos
products are brake linings (category 6813), which numbered approximately
17
Chrysotile Asbestos
860,0002 articles, gaskets (category 6812) numbering approximately 200,000 and
clutch facings numbering 6000 articles. Detailed information on the customs
tariff codes for product categories that may contain asbestos (according to
product type, volume, and number of companies importing, is provided in
Appendix 3, Figs 1B,C,and D).
NICNAS surveys of importers
Surveys were conducted by NICNAS in 1995 (see also section 5.4) to determine
the accuracy and representitiveness of the 1994 customs data (see Appendix 2 for
details of the surveys conducted). A total of 843 companies ranging from
shipping, building, timber, marine, engineering, aircraft, industrial equipment and
machinery, vehicle importers and manufacturers and automotive spare parts
suppliers were surveyed throughout all States and Territories in Australia.
Of the 843 companies, approximately 766 companies used products in the
categories for friction materials and articles thereof and gaskets. The results of
the survey of these companies are discussed in Appendix 4.
Of the remaining 77 companies, 37 imported fibre-cement products (which may
or may not contain asbestos) and 40 imported `asbestos products not otherwise
specified'.
Customs data indicated that there were two categories (6811 and 6812) which
comprised products other than friction materials. The survey of importers of
fibre-cement products in this customs category (6811) showed that asbestos
containing fibre cement products are unlikely to be imported into Australia. All
15 companies surveyed in this category confirmed this. The remaining 6
companies were unable to be contacted.
For category 6812 (asbestos products other than goods in 6811 and 6813) the
survey of importers showed that the major import was gaskets. The survey
showed that asbestos and non-asbestos gaskets are being used in both the
automotive industry and for industrial applications and that a greater numbers of
non-asbestos gaskets were used in industrial applications.
Other uses of asbestos identified (other than in friction material and gaskets)
were: blades in high vacuum pumps, asbestos yarn for packing, asbestos gloves
and asbestos washers for miners oil flame safety lamps. It should be noted that
these were all one-off imports (refer to Appendix 4 for a breakdown of survey
responses).
Trends in importation of brake linings and gaskets (Customs data)
Due to changes in Customs categories or lack of identification within a category,
trends could only be followed for brake linings and gaskets since 1994. Table 3
provides figures for the importation of brake linings and gaskets for calendar
years 1994 to 1997, together with the first 8 months data for 1998.
2
This figure does not include brake pads "that may contain asbestos" under Customs code
6813.10.10.45, which totaled approximately 100,000 articles in 1997.
18 Priority Existing Chemical Number 9
Table 3 - Importation of asbestos and non-asbestos brake linings
and asbestos gaskets for the period 1994-19981
Number of articles2
19983
Product and Customs 1994 1995 1996 1997
category (Jan ?Aug)
Asbestos brake linings 492,295 47,735 43,087 771,182 (548,692)
for passenger cars
6813.10.10.41
6813.10.10.42
Non-asbestos brake 70,109 321,472 485,812 2,084,963 (4,057,143)
linings for passenger
cars
6813.10.10.43
6813.10.10.44
May or may not contain 218,033 65,849 35,041 104,261 (76,876)
asbestos - brake linings
for passenger cars
6813.10.10.45
Asbestos brake linings 103,087 79,443 22,922 90,926 (87,994)
for industrial use
6813.10.90.46
6813.10.90.47
Non-asbestos brake 308,864 557,167 371,381 1,889,537 (203,259)
linings for industrial use
6813.10.90.48
6813.10.90.49
Asbestos gaskets for 45,682 49,519 52,707 59,811 (46,478)
passenger cars
6812.90.10.57
110,003 176,159 196,254 139,745 (87,386)
Asbestos gaskets for
industrial use
6812.90.90.59
1
Data provided by Australian Bureau of Statistics (ABS)
2
For friction products, industry have advised that, for brake linings/pads, the number of articles should
be multiplied by 4 (i.e., no. of articles per pack), in order to obtain the actual number of linings/pads.
3
Data for 1998, are for 8 month period only.
Passenger cars
When comparing the use of asbestos and non-asbestos brake linings, the figures
indicate that since 1994 significantly more (up to 10 fold) non-asbestos than
asbestos brake linings have been imported for use in passenger cars.
A sharp decrease in the use of asbestos brake linings in passenger cars was seen
in 1995 and 1996, which correlated with increased imports of non-asbestos
linings. However 1997 and 1998 saw large increases in importation of both
asbestos and non-asbestos linings (up to 10 fold), compared to 1996 quantities.
All asbestos brake linings imported between January and August 1998 were of
the moulded type (category 6813.10.10.41).
The use of asbestos gaskets in passenger cars appears to have gradually increased
(about 10% per annum) since 1994. There are no customs data for non-asbestos
gaskets.
Customs data verification
In order to validate Customs data for passenger car brake linings, an ABS
investigation (at the request of NICNAS) was carried out for 1998 import data for
19
Chrysotile Asbestos
brake linings. Customs brokers were asked to verify the accuracy of records for
the months March to August 1998. This process identified errors in the data
classified to 6813.10.10.42 (amendments included in Table 3). No errors were
found with regard to data classified to category 6813.10.10.41. Extrapolation of
this data provides an estimated annual total of 800,000 articles (i.e. 3,000,000
brake linings/pads ?see footnote to Table 3) imported for 1998, which is
consistent with data for 1997. It was concluded that either, imports have risen
significantly since 1995/96 or that the 1995/96 data is incomplete (industry
sources have stated that import figures for category 6813.10.10.41 for 1995/96
appear to be underestimates). With regard to the latter possibility, miscoding was
not evident from an analysis of other categories for asbestos and non-asbestos
brake products, in particular, data for category 6813.10.10.45 (see Table 3).
Industrial applications
More than three times the amount of non-asbestos than asbestos brake linings was
imported for industrial applications in 1994, the proportion of which has doubled
annually, up to around twenty fold in 1997. Data for 1998, although incomplete,
indicate a sharp decrease in non-asbestos imports.
As with passenger cars, a significant decrease in imports of asbestos linings for
industrial applications was seen in 1996 and, also as seen for passenger vehicles,
increased (around 4 fold) importation (see section 5.2.3 for qualification) of
asbestos linings was seen in 1997 and 1998.
The use of asbestos gaskets in industrial applications has gradually increased
(about 10% per annum) from 1994 to 1997. There is no Customs coding for non-
asbestos gaskets.
5.3 Current manufacture of chrysotile products
Imported raw chrysotile is used by 3 companies in the manufacture of asbestos
products (see Appendix 1 for details). Applicants provided the following
information on current manufacture of chrysotile products in Australia.
5.3.1 Bendix Mintex Pty Ltd
Bendix Mintex uses raw chrysotile in the manufacture of disc brake pads,
commercial vehicle blocks and linings and passenger car drum linings. Most of
the sales volume is for passenger vehicles, with commercial vehicle blocks and
linings comprising less than 10% of sales.
These products are supplied to:
? the Australian automotive aftermarket via automotive wholesalers, resellers,
and brake specialists;
? the Australian car companies aftermarket service and distribution outlets; and
? export markets direct to distributors overseas.
Bendix Mintex also sell brake blocks and linings to Australian brake shoe re-
manufacturers (bonders) and overseas distributors. Products are not sold directly
to the public. Bendix Mintex no longer manufactures clutch facings. Brand
names for Bendix asbestos-containing friction products are Bendix and Don.
20 Priority Existing Chemical Number 9
5.3.2 Richard Klinger Pty Ltd
Richard Klinger Pty Ltd uses raw chrysotile in the manufacture of compressed
asbestos fibre (CAF) sheeting. This product is sold in sheeting and cut gasket
form and is used to make spiral wound gaskets that will resist pressure,
temperature and aggressive media. Such gaskets are used by a broad range of
industries which include: petrochemical, shipbuilding, petroleum refineries, pulp
and paper mining, chemical processing and food processing.
5.3.3 Vivacity Engineering Pty Ltd
Vivacity Engineering use chrysotile as a `non-sag' additive in epoxy resin
adhesives used for affixing marble and granite panels to walls of buildings. The
final product contains 2% by weight chrysotile.
5.4 NICNAS surveys on the use of chrysotile products
Because of the difficulties in distinguishing between asbestos or non-asbestos
products from Customs data (see Section 5.2.1), a NICNAS survey (see also
Section 5.2.3) of potential importers/users of asbestos products was carried out
for the following product categories:
? 6811 - Fibre cement products;
? 6812 - Asbestos products other than goods of 6811 or 6813; and
? 6813 - Friction materials and articles thereof.
For full details of survey methodologies see Appendix 2.
5.4.1 Automotive industry
The major use of asbestos in the automotive industry is in friction materials
(brake linings, disc brake pads, brake blocks and clutch facings) and gaskets.
Since 1994, the vast majority of brake linings being introduced into Australia are
non-asbestos, the use of which is divided almost equally (between 1995 and
1997) between industrial and automotive applications (see Table 3). The 1994
survey indicated that the majority of disc brake pads (no Customs category)
imported into Australia were non-asbestos for use in both automotive and
industrial applications. Brake blocks (no Customs category) were still being used
in the automotive industry but their use was minimal. Brake blocks (non-
asbestos) were more commonly used for rail vehicles and other industrial
applications.
The NICNAS survey confirmed that clutch facings are predominantly non-
asbestos. The 1997 Customs data showed that the number of asbestos clutch
facings imported into Australia were around 6,000 in contrast to 600,000 non-
asbestos facings. According to ABS data, none of the asbestos clutch facings
imported in 1997, were for use in passenger vehicles.
The survey also confirmed that alternatives are available for many applications.
This is discussed in more detail in Section 11.
21
Chrysotile Asbestos
New vehicles
Out of 26 companies, 25 stated that they are using non-asbestos original
equipment in all current models. One company (Ford Motor Australia) reported
that they are still using asbestos parts in 2 current models: asbestos head gaskets
for the Econovan and asbestos rear brake linings for the Ford Utility. Ford
Australia introduced non-asbestos components for their most popular models (e.g.
Laser, Falcon and Fairlane) between 1989 and 1995. Other current models
manufactured by Ford have been asbestos-free since their introduction.
Asbestos parts are imported by 6 of the 26 companies (BMW, Ford, Mazda,
Mitsubishi, Nissan and Toyota) with five companies using asbestos parts for
superseded vehicles and one company (Ford Australia) using asbestos parts in
superseded and current models. In response to the question whether asbestos
parts in superseded models could be replaced with non-asbestos parts, companies
stated that although this was possible for certain vehicles, the extent to which this
was possible had not been investigated. This would require actual `on-vehicle'
testing or other suitable simulation in order to determine the adequacy of non-
asbestos replacement parts.
The majority of the vehicle manufacturing companies stated that they have had
policies in place in regard to not using asbestos components in new vehicles for
the last 5 to 10 years.
To further supplement the survey, the use of asbestos and non-asbestos parts by
companies importing commercial vehicles (trucks, buses and coaches) and not
included above, was investigated. Four major companies namely Hino,
Kenworth Trucks, Man Bus and Volvo Trucks were contacted with 3 companies
responding. Responses indicated that the majority of current commercial vehicles
have non-asbestos `original' equipment. All 3 companies also reported that non-
asbestos parts can replace asbestos parts in superseded vehicles and that use of
non-asbestos parts was generally introduced in the late 1980s.
Automotive Aftermarket Survey
The small number of new cars manufactured in Australia compared to the number
of imported (obtained from Customs data) and manufactured asbestos friction
materials and gaskets, suggests that there must be significant use of asbestos
products in the aftermarket industry.
NICNAS conducted an Automotive Aftermarket Survey in which service
garages, brake bonders and gasket manufacturers were surveyed on the use of
asbestos and non-asbestos products. For details of this survey see Appendix 2
and Section 6 (Occupational exposure).
Results from these surveys indicated that a high proportion of the work with
friction products (up to 90% in brake bonding workshops) involved the use of
chrysotile products. However, the reported availability of new products (e.g.
clutch kits and disc brake pads) which are already cut to size, limit the amount of
machining (sanding, grinding and cutting) that is now required. In addition,
workshops reported that the majority of clutches which come in kit-form are non-
asbestos.
22 Priority Existing Chemical Number 9
Currently, large quantities of asbestos friction materials are still used in asbestos
and non-asbestos original equipment vehicles. The `Automotive Aftermarket
Survey' identified some of the reasons for the continued use of asbestos products
in the automotive replacement aftermarket and these are discussed in detail in
Section 11.
The continued `aging' of the Australian vehicle fleet is considered to be the
predominant factor in the sustained use of asbestos friction products. Recently
(June 1997), a comprehensive national survey of motor vehicles published by the
Australian Bureau of Statistics found that between 1971 and 1995, the average
age of the vehicle fleet increased steadily from 6.1 years to 10.6 years. Also the
proportion of cars that were at least a decade old rose sharply from less than a
fifth to more than a half of total vehicles (Australian Bureau of Statistics, 1997).
Figure 3 provides information on the age of vehicles in Australia in 1995. For
comparison, information on the average age of cars in other countries is providing
in Figure 4. It can be seen that in 1995, Australia had the highest percentage
(52%) of cars older than 10 years, with Japan the lowest (<0.5%). Data for UK,
USA, Italy and Spain were similar with percentages ranging from 28% to 31%,
with France (23%) and Germany (22%) being slightly lower.
23
Chrysotile Asbestos
Figure 3 ?Age of vehicles in Australia in 1995
100
90
Percentage of vehicles older than age specified
80
70
60
50
40
30
20
10
0
25 23 21 19 17 15 13 11 9 7 5 3 1
Age in years
Source: Australian Bureau of Statistics (1995)
Figure 4 ?Proportion of cars older than 10 years in 1995, by
country
60
52
50
40
Percentage
31 30 29 28
30
23 22
20
10
0.48
0
Spain
Germany
France
Japan
Australia
USA
UK
Italy
Source: Federal Chamber of Automotive Industries (1977)
24 Priority Existing Chemical Number 9
5.4.2 Aircraft industry
Surveys were sent to the two major Australian airlines, Ansett and Qantas. Only
Qantas responded to the survey. The company stated that asbestos has special
physical properties that are not currently available in alternative materials.
Consequently most aircraft engines, particularly older designs, use parts
containing asbestos. These parts are usually in the form of gaskets and seals and
comprise asbestos in a composite or matrix of other materials. While extensive
efforts worldwide have been made to retrofit many of these parts with non-
asbestos materials, alternatives have not been found for several applications.
Qantas supplied information on the current use of asbestos parts in two different
aircraft (Boeing 767 and Boeing 747) and the information is summarised in Table
4.
Table 4 - Use of asbestos parts in aircraft (NICNAS Survey 1994)
Product Use
Consumables For component flange interfaces in high temperature
e.g. sealing goop applications (contains 1-10% chrysotile).
Clamps Metal clamps with polytetrafluoroethylene (PTFE) bound
asbestos cushions are used in many locations on gas turbine
engines, to insulate hydraulic tubes and fuel lines from the high
temperatures cases to which these tubes and lines are secured.
The metal clamps also protect tubes from vibration and chafing.
Gaskets and seals Various flange interface surfaces are assembled with asbestos-
containing seals.
Rub pads & blocks Asbestos bound into a matrix is used in some aircraft
applications to prevent metal to metal contact between parts,
usually in high temperature and high vibration areas.
Heat shields & Insulating shrouds are used around gas turbine to protect
shrouds vulnerable components (such as electrical components and fuel
systems) from the very high temperature combustion and
turbine section.
5.4.3 Industrial equipment and machinery
To determine whether asbestos friction parts and gaskets are continuing to be
used in industrial equipment and machinery e.g. forklift, cranes used in mining,
miniloader, tractors, hoisting equipment, diesel engines and diggers surveys of 15
companies were carried out. Fourteen companies stated that they are using non-
asbestos parts in all current models. These companies also stated that they are
replacing asbestos parts with non-asbestos parts in superseded models. Most of
the companies stopped using asbestos parts in the late 1980s.
One company reported that they are still using asbestos gaskets in diesel engines
due to the lack of an effective substitute. One manufacturer of asbestos gaskets
reported that their business consisted of 25% asbestos and 75% non-asbestos
gaskets, respectively. This company supplied asbestos gaskets to industries
which use gaskets in special applications e.g. high temperature and high pressure
applications in oil refineries and chemical plant or when specially requested by
customers.
25
Chrysotile Asbestos
The NICNAS Survey (1994) also identified the use of asbestos brakes in
draglines3 used in the coal industry. Although it is possible that there are some
asbestos brakes still in use in older draglines, mining companies have generally
replaced these with non-asbestos parts (since the late 1980s).
5.5 Current exports of asbestos and asbestos products
Export of raw asbestos from Australia ceased in 1984. A total of 22 tonnes of
raw asbestos was exported during 1984.
Customs export data for asbestos products from 1990 to 1997 were analysed.
Specific information on exports for this period, such as product category, quantity
and cost are presented in Appendix 8. Customs coding for asbestos exports is not
as detailed as that for imports.
Only one category in the export data, "articles of asbestos", which includes
gaskets, differentiates between asbestos and non-asbestos articles. The other
three categories; brake linings and pads, transmission linings and friction
materials for clutches do not distinguish between asbestos and non-asbestos
products. The export data were found to be variable and no trends could be
established. The export and import Customs categories did not correlate, hence
direct comparisons could not be made.
Bendix Mintex stated that friction products, including friction material mixes
containing chrysotile, are exported to friction material suppliers and
manufacturers in the Asia Pacific Region. Details requested, including quantities
were not provided by Bendix Mintex, although they have indicated that such
exports represent some 20-30% of total asbestos market volume.
Richard Klinger manufacture both asbestos and non-asbestos sheeting and spiral
wound gaskets for export. Of the total asbestos and non-asbestos products
manufactured in Australia, 78% and 36% are exported, respectively.
Vivacity Engineering report that virtually all of their chrysotile-containing
product is exported.
5.6 Summary
Raw chrysotile is no longer mined nor exported in Australia and is imported at
approximately 1000 ?2000 tonnes per year. This level has been stable since
1989 and shows no sign of decline/increase.
The current major uses of raw chrysotile imported into Australia are for the
manufacture of friction materials and CAF sheeting for gasket production for
both industrial and automotive applications. Although a significant proportion of
asbestos braking components and gaskets are still used for these applications, the
majority are asbestos free.
A small quantity of raw chrysotile is used in the manufacture of a `non-sag'
additive in epoxy resin adhesives. The manufacturer reports that this product is
being phased out and currently is virtually all exported.
3
A dragline is a type of excavating equipment used in mining which casts a rope-hung bucket for
collection and deposition of excavated material.
26 Priority Existing Chemical Number 9
A small number of `one-off' uses for asbestos products exist and these include
blades in high vacuum pumps, asbestos yarn in packing, asbestos gloves and
asbestos washers for miners oil flame safety lamps. Investigations confirmed that
chrysotile is no longer imported for a range of other past applications, such as
pipes, textiles etc. Investigations have confirmed that the importation of asbestos
fibre cement products is unlikely.
Chrysotile brake linings/pads and clutch facings continue to be imported into
Australia for use in passenger motor vehicles and industrial applications. The use
of brake blocks in Australia is declining with the predominant use in industrial
applications (e.g. railway industry and mining equipment). The majority of these
imports are non-asbestos.
For new vehicles, only one company is using asbestos `original' parts in just two
of their current models. New vehicles include passenger cars, trucks, light trucks
and heavy trucks. The majority of new vehicle companies have policies in place
regarding transition to asbestos substitutes. Approximately 20% of the Australian
new vehicle manufacturing/importing companies import asbestos products for
superseded models. Although a sharp decrease in imports of asbestos brake
linings for passenger cars was seen in 1995 and 1996, a marked increase was
apparent (see section 5.2.3 for qualification) in 1997 and 1998. The reason(s) for
this trend is unclear, but may reflect either:
? increased use in the domestic market;
? miscoding of products by importers for 1995/96; and/or
? transcription errors in customs data for 1995/96.
Imports of non-asbestos brake linings for passenger cars have also increased
significantly, from around 100,000 in 1994 to 4 million in the first 8 months of
1998.
Asbestos friction materials are extensively used in the vehicle aftermarket. This,
together with the fact that Australia has a significantly high proportion of `old'
vehicles (compared to other developed countries), is the predominant factor in the
sustained manufacture and import of asbestos brake linings.
It is not possible to determine the proportion of asbestos versus non-asbestos
gaskets in use from Australian Customs categories. A significant number of non-
asbestos gaskets are used for industrial applications, however, investigations
indicate that there continues to be a large number of asbestos gaskets in use for
both industrial applications and passenger cars. The importation of asbestos
gaskets for industrial applications averaged at around 150,000 per annum for
1994 to 1997, but shows an increasing trend (about 10% per annum) for
passenger cars during this period.
The majority of industrial equipment and machinery (e.g. agricultural
machinery), has non-asbestos original parts. A significant number of companies
use non-asbestos in both superseded and new equipment and machinery and most
stopped using asbestos parts in the late 1980s.
In the airline industry asbestos parts are still being used in new and older aircraft
e.g., gaskets and seals. However, as with other industries there is a continued
effort towards the identification of possible substitutes.
27
Chrysotile Asbestos
Australian export of raw asbestos ceased in 1984. As several customs export
categories include articles which `may or may not contain asbestos' and since the
customs tariff classifications for imports and exports are different, the amount of
export trade in specific asbestos products has proved difficult to determine.
Export data for certain brake linings and pads and transmission linings for the
period 1991-1998 can be found in Appendix 8. Detailed export data (quantities)
were not provided by any of the applicants. However, Bendix Mintex, Richard
Klinger and Vivacity Engineering, reported that exports constituted up to 30%,
80% and `nearly all', respectively, of their manufactured chrysotile products.
28 Priority Existing Chemical Number 9
6. Occupational Exposure
Workers may be exposed to chrysotile during warehousing and distribution,
manufacture, processing and end-use of products containing chrysotile. The
major route of worker exposure is inhalation, with oral exposure likely to be a
very minor route. Consistent with the objectives of this assessment, this section
covers those uses currently being introduced either by import or manufacture.
However, there are sources of data relating to other exposures which would need
to be included in any consideration of these other scenarios. This includes
Australian data on worker exposure in some asbestos contaminated Australian
mines (Rogers et al. 1997).
6.1. Exposure to chrysotile during Australian manufacturing processes
This section covers the following: manufacture of friction materials (brake disc
pads, brake linings, brake blocks and clutches), manufacture of asbestos fibre
(CAF) and processing (of CAF) in the production of gaskets and manufacture of
epoxy resin adhesive. Information in this section was provided by Bendix
Mintex, Richard Klinger and Vivacity Engineering.
6.1.1 Manufacture of friction materials
Chrysotile friction materials are now manufactured at only one workplace,
Bendix Mintex Pty Ltd, Ballarat, Victoria in Australia.
Manufacturing processes are as follows. Prior to mixing, 50 kg plastic bags of
raw chrysotile are transferred to the pre-weigh department with other ingredients
required to make up a product mix. Following the transfer of other ingredients to
the mixer, bags of raw chrysotile are placed in the mixer and opened (by knife)
under dust extraction. The empty chrysotile bag is pushed through a chute in the
mixer and delivered into a plastic bag attached to the mixer. When full, this
plastic bag is sealed and eventually taken to a controlled disposal site. Mixing is
a closed process.
After mixing, the product is emptied under extraction into large bins. These bins
are placed in enclosures prior to decanting into smaller mix buckets for weighing
and use in moulding and finishing processes. The mix is weighed (manually)
under dust extraction and placed into a die for moulding. The moulding of
asbestos product is a hot process. When this process is complete, the moulded
product undergoes finishing processes, which include grinding, grooving and
drilling. All of these processes are conducted under dust extraction.
The finished products, disc pads and commercial vehicle brake blocks and
linings, are wrapped and packed into sealed containers.
Potential for exposure
Potential for exposure exists during the following operations:
? opening and emptying bags of chrysotile into the mixer;
29
Chrysotile Asbestos
? during the moulding and finishing processes;
? during maintenance of processing equipment; and
? handling of damaged bags containing raw chrysotile.
According to Bendix Mintex around 700 workers are employed at the plant.
Approximate numbers of workers and typical exposure times for the various
groups of workers are summarised in Table 5.
Table 5 - Number of workers and duration and frequency of exposure
No. of Maximum exposure per
Category of workers
workers employee (h/day/year)
Management-supervisory - non-factory 29 minimal
Management- factory 4 1 h/100 days/year
Supervisory - factory 16 3.6 h/230 days/year
Professional - non-factory 6 minimal
Professional - factory 10 1 h/30 days/year
Trades/skilled - non-factory 44 minimal
Trades/skilled - factory 26 3.8 h/115 days/year
Engineering/technical 55 3.8 h/115 days/year
Clerical and related 40 minimal
Sales 6 minimal
Plant operating 1 minimal
Process and related 501 7.6 h/ 230 days/year
Production support staff, who include maintenance, engineering and quality
assurance workers, have various levels of involvement in the production process.
Office employees (management, clerical, sales) have minimal involvement in the
production process except on occasions when they work in the factory, for
example, during peak production times. Bendix Mintex has stated that this has
occurred only on rare occasions and is not expected in the future.
Atmospheric monitoring
The monitoring of worker exposure to chrysotile at Bendix Mintex is performed
in accordance with the standard membrane filter method (MFM), as outlined in
the Guidance Note on the Membrane Filter Method for Estimating Airborne
Asbestos Dust (NOHSC, 1988). Primarily personal monitoring is conducted,
however static monitoring is also performed on a limited basis.
Personal monitoring data provided by Bendix Mintex (Ballarat site) for 1992 to
1997 is summarised in Table 6 and in Figure 5. Approximately 84% of the 461
samples taken between 1992 and 1997 were <0.1f/mL; 10% were 0.1 - <0.2
f/mL, 6% were 0.2 - <0.5 f/ml and <1% were 0.5 f/mL. There was no trend in
the data over time.
For all activities, over this period, between 54 and 97% of all samples were <0.1
f/mL. Weighing and drilling operations recorded a higher percentage of results >
0.1 f/mL, which was to be expected as these activities are more likely to release
30 Priority Existing Chemical Number 9
chrysotile fibres. Only during weighing4 were exposures (2 samples) recorded
>0.5 f/mL, with the highest result being 1.02 f/mL.
Apart from 2 samples in 1996 (3% of total samples), all were below 0.5 f/mL for
other years (see Table 6).
Table 6 ?Personal air monitoring data for airborne fibres* (1992 to
1997) at Bendix Mintex plant
Year Total no. Results Summary
of
Range Sample Groupings
samples
(f/mL)
Fibre range No. of
(f/mL) samples
22 100% of samples < 0.5 f/mL
1992 29 0.00 ?0.09 <0.1
> 0.1 - < 0.2 7 76% of samples < 0.1 f/mL
> 0.2 - < 0.5 0
51 100% of samples < 0.5 f/mL
1993 59 0.01 ?0.43 <0.1
> 0.1 - < 0.2 4 86% of samples < 0.1 f/mL
> 0.2 - < 0.5 4
1994 111 0.01 ?0.27 <0.1 108 100% of samples < 0.5 f/mL
> 0.1 - < 0.2 2 97% of samples < 0.1 f/mL
> 0.2 - < 0.5 1
1995 103 0.01 ?0.16 <0.1 96 100% of samples < 0.5 f/mL
> 0.1 - < 0.2 7 93% of samples < 0.1 f/mL
> 0.2 - < 0.5 0
1996 87 0.01 ?1.02 <0.1 47 97% of samples < 0.5 f/mL
> 0.1 - < 0.2 18 54% of samples < 0.1 f/mL
> 0.2 - < 0.5 20
> 0.5 2
58 100% of samples < 0.5 f/mL
1997 72 0.00 ?0.28 <0.1
11 81% of samples < 0.1 f/mL
> 0.1 - < 0.2
> 0.2 - < 0.5 3
* Monitoring and analysis method (MFM/PCM) does not enable differentiation between chrysotile and
other fibres
Sampling carried out using SKC portable programmable pumps (0.5 L/min) with cellulose membrane
filter.
Data provided by Bendix Mintex.
4
Respiratory protection is used in the weighing area
31
Chrysotile Asbestos
Figure 5 ?Personal air monitoring data (1992 to 1997) at Bendix
Mintex plant.
120
100
80
A
B
60
C
D
40
20
0
1992 1993 1994 1995 1996 1997
Years
A <0.1 f/ml
B 0.1 - <0.2 f/ml
C 0.2 f/ml - <0.5 f/ml
D 0.5 f/ml
6.1.2 Manufacture of compressed asbestos fibre sheeting (CAF) and gaskets
Compressed asbestos fibre (CAF) sheeting, using raw chrysotile, is manufactured
in Australia by Richard Klinger Pty Ltd at Booragoon, Perth, Western Australia.
The majority of the CAF sheeting is then exported and the remainder processed
into finished cut gaskets (for use in industrial applications) at both their
Melbourne and Perth (post 1996) sites.
At Booragoon, the bags of raw chrysotile are inspected to ensure there are no
broken bags. If broken, the bags are sealed by operators and immediately
consumed in the manufacturing process. Where necessary, the surrounding area
is vacuumed using high efficiency cleaners. The polyethylene bag is removed
from the raw chrysotile using a debagging machine, which is enclosed and under
negative pressure. The machine disposes of the chrysotile containing bag
automatically into a fresh sealed plastic bag. The sealed bag is then removed
from the machine manually.
32 Priority Existing Chemical Number 9
The production of CAF sheets is a closed process. The chrysotile fibres are
transferred under negative pressure through conduits attached to the bagging
machine to the hammer mill, where the fibres are milled and introduced into a
mixing machine via a closed loop system. The fibres are then encapsulated by
combining with various grades of rubber to form a wet mash, which is then
passed through a calendering machine to form CAF sheets.
The CAF sheets are then printed and trimmed using knife action tooling, for
example, a guillotine. The CAF sheets are cut to size using knife bladed tools.
For spiral wound gasket production, imported rolls of asbestos filler material are
slit using a rotary die block. The slit material is then wound between alternate
layers of stainless steel. The finished goods are stored prior to packing for
distribution to customers.
Gasket off-cuts also undergo secondary manufacturing at the Perth site. These
off-cuts are recycled for further use.
Gasket cutting from CAF is also carried out by other workshops and this is
discussed under end-use in section 6.2.
Potential for exposure
There is potential for worker exposure during the following operations:
? when damaged bags are encountered during raw material preparation;
? when removing plastic bag from debagging machine;
? during the maintenance of processing equipment;
? during finishing processes and gasket cutting operations; and
? when the rolls of asbestos filler are slit for spiral wound gasket production.
Workers at Richard Klinger wear cotton overalls, half face mask respirators (with
class M cartridges) and leather gloves when handling chrysotile or conducting
equipment maintenance operations. The number of workers, maximum duration
and frequency of exposure at the Perth and Melbourne plants are summarised in
Table 7.
Laboratory staff conduct a number of destructive and non-destructive tests (Perth
site) on gasket material. The only destructive test used where there is a potential
for release of fibres is the tensile test. Tensile tests are infrequently performed on
samples of compressed asbestos fibre sheeting. A maximum of 5 samples are
tested per week with a test time of approximately 1.5 minutes per each sample.
Control measures in place include the use of disposable masks appropriate for
asbestos fibres and wipe down (with damp cloth) of testing equipment.
Atmospheric monitoring
Both personal and static monitoring are conducted at Richard Klinger sites. At
the Perth site, air monitoring is carried out weekly at various testing sites,
including the raw material preparation area and the calendering and guillotining
process areas. At the Melbourne site, air monitoring is carried out every 2 years.
All testing is performed according to the NOHSC Asbestos Code of Practice
(NOHSC, 1988), with the sampling period between 5 and 8 hours. Air
monitoring data provided by Richard Klinger is summarised in Table 8
33
Chrysotile Asbestos
(Melbourne site) and Table 9 (Perth site). At the Melbourne site, where raw
chrysotile is not handled, all personal samples were <0.5 f/mL. Although data
were only provided for a few workers at each location, Richard Klinger have
stated that locations monitored represent the highest CAF usage areas.
Table 7 - Worker exposure at Richard Klinger sites
Max. exposure/employee
Category of workers No. of workers
(h/day/year)
Booragoon, Perth, WA - CAF production
Raw material preparation 6 4 h/231 days/year
Calendering 10 4 h/231 days/year
Finishing 4 4 h/231 days/year
Stores 5 1 h/231 days/year
Gasket cutting 3 3 h/231 days/year
Maintenance personnel 5 1 h/231 days/year
Laboratory staff 1 0.75 h/231 days/year
Melbourne, VIC - Gasket production
Gasket cutting 16 6 h/231 days/year
Spiral wounding 10 6 h/231 days/year
Stores 6 3 h/231 days/year
data provided by Richard Klinger
Table 8 - Asbestos air monitoring data (1989 - 1996) at Richard
Klinger, (Melbourne plant).*
Year Location Sampling No. Concentration
type samples (f/mL)
Spiral wound gasket na na 0.04
1989
area
1991 Industrial cutting shop personal 2 below limit of detection
static 2 < 0.01, 0.01
Handcut area personal 1 below limit of detection
static 1 < 0.01
Stores personal 1 below limit of detection
Spiral Wound area personal 2 below limit of detection
static 2 0.01
1993 Cutting shop na na 0.04
1995 Handcut area personal 1 < 0.05
Press personal 3 <0.05
Press static 2 0.01
Small guillotine static 1 < 0.01
Packing area static 1 < 0.01
na = not available
* data provided by Richard Klinger
34 Priority Existing Chemical Number 9
35
Chrysotile Asbestos
36 Priority Existing Chemical Number 9
A total of 232 personal samples (including 17 overloaded or damaged filters)
were taken during raw material preparation at the Richard Klinger Perth site
between 1991 and 1996. Of the personal samples, 58% were <0.1 f/mL, 18%
were 0.1 - <0.2 f/mL, 23% were 0.2 - <0.5 f/mL and 1 sample was 0.5 f/mL
(i.e. 0.8 f/mL). The personal monitoring data for 1992 to 1996 is presented
according to year in Figure 5. There appears to be no trend in measurements over
time. Static samples (94) were recorded during guillotine and calender/trimming
activities at the Perth site. All samples were 0.05 f/mL.
Figure 6
Persoanl Air Monitoring Data (1992-1996)
at Richard Klinger (Perth site) during
Raw Material Preparation
90
80
70
60
50
40
30
20
10
0
1992 1993 1994 1995 1996
Years
< 0.1 f/ml
0.1 - < 0.2 f/ml
0.2 f/ml
37
Chrysotile Asbestos
6.1.3 Manufacture of epoxy resin adhesive
Vivacity Engineering (New South Wales) use chrysotile as a `non-sag' additive in
the formulation of an epoxy resin adhesive for affixing marble and granite panels
to the walls of buildings.
Chrysotile is imported in compressed form in 15 kg paper bags, wrapped in
plastic. Approximately 500 bags are imported in a shipping container which is
stored on site.
The liquid ingredients are first added to the mixer. Bags containing chrysotile are
manually opened, the chrysotile weighed and then added to the mixing vessel. A
lid is placed on the vessel which is exhaust ventilated. Mixing takes
approximately one hour. The product is a thick paste and is mechanically forced
out of the vessel using a plunger. The product is produced in batches for
approximately 50% of the year. It is packaged in 2, 4 or 20 litre plastic buckets.
Any spills or loose asbestos released during cutting are collected during
vacuuming and waste is disposed of in drums to a licensed contractor.
At the time of the survey, 17 workers were employed at the site, around half of
which were engaged on the factory floor and storage areas. Workers wear 3M
8710 respirators when handling and weighing asbestos. Gloves are worn by all
factory floor workers.
Potential for exposure
Exposure to chrysotile may occur during the following operations:
? when damaged bags are encountered during storage and raw material
preparation;
? when manually opening chrysotile bags and adding chrysotile to the mixing
vessel;
? during general clean-up and disposal.
Atmospheric monitoring
Vivacity Engineering advised that no air monitoring has been conducted at this
site.
6.2 Exposure during end-use in Australian industries
The main end-uses for chrysotile products are friction materials (brake disc pads,
brake linings, clutch facings and brake blocks) and gaskets in the automotive
aftermarket and for industrial applications. Worker exposure may occur during
the removal and replacement of worn parts. Wear and tear of parts may result in
production of friable chrysotile (dust) which may be easily disturbed and become
airborne during repair and removal. In addition, modification of parts, such as by
cutting, grinding, sanding and drilling may release fibres.
38 Priority Existing Chemical Number 9
It has been estimated that up to 10,0005 workers are intermittently exposed to
chrysotile during end-use. These workers are found in the construction industry,
automotive brake and clutch repair, gasket cutting and brake bonding workshops
and other service industries (NOHSC, 1995a).
There is limited occupational exposure data available for end-use. Australian
data include:
? a survey (carried out by NICNAS) of the automotive aftermarket (this also
included a gasket cutting workshop) see Appendix 2;
? data from Western Australia for service garages;
? data on gasket removal and installation at a single company; and
? data on preparation of gaskets (for use in engineering applications).
Potential exposure to chrysotile for end-users exists when fibres are released,
such as in the following situations:
Gasket workshops
? during fabrication of CAF sheeting to produce gaskets - this may involve
cutting, sawing and drilling.
Brake bonding industry
? when worn brake pads and clutch facings are stripped from their metal
supports; and
? during assembly of disc brakes and clutches - this may involve grinding
(grinding generates high volumes of dust and very fine fibres).
Garage service workshops
? during changing of worn brake disc pads, brake shoes and clutch facings.
6.2.1 End-use monitoring data
NICNAS Automotive Aftermarket Survey (Sydney, NSW)
A small survey (carried out by NICNAS) in 1996 of the Automotive Aftermarket
industry was conducted to gauge the relative usage of both asbestos and non-
asbestos products in garages and workshops and to assess occupational exposure
to chrysotile in the workplaces. Detailed information on the methodology of this
survey can be found in Appendix 2.
Control measures used in the workshops were also investigated and this
information is summarised in Table 10.
The automotive aftermarket survey found that:
? In service garages, exposure to asbestos may occur during brake changes and
clutch repair, with the number of hours per day/week varying from garage to
5
The Victorian Asbestos Diseases Society are of the opinion that this figure is likely to be a
significant underestimate, based on assumptions derived from ABS statistics for the numbers of
workers reported (55,000 at September 1997) under the category `automotive repair and services'.
39
Chrysotile Asbestos
garage. The service garages surveyed indicated that they rarely undertook
cutting, grinding or sanding of asbestos products.
? In brake bonding the work normally consists of removal and replacement of
worn brake pads and clutch facings. Worn pads and facings are stripped from
their metal backing by abrasive action. Once the metal has been cleaned new
linings are glued into place, cured in an oven, and then ground to size. Some
cutting of new linings is carried out, but in most cases, the brake and clutch
material comes precut.
? In gasket workshops cutting and stamping (by machine) takes place. Sawing
and drilling are sometimes performed in the finishing process. The average
exposure time was 5 h/week however, the number of hours was dependent on
customer orders and hence varied considerably.
Personal and static monitoring was also conducted (using MFM) at all workshops
surveyed and results are summarised in Table 11. The TEM results and
corresponding MFM results are provided in Table 12.
The light microscopy monitoring results indicate that exposure to chrysotile was
greatest during the cutting and grinding of brake shoes. The only results >0.05
f/mL were obtained in brake bonding workshops, with the highest personal
monitoring result being 0.2 f/mL. However, the sampling duration was less than
the preferable minimum of 4 hour and therefore the results cannot be directly
compared with the TWA exposure standard. The results indicate that exposure to
chrysotile on a task basis was less than 0.05 f/mL (the detection limit of the
MFM), during repair work in service garages. As this is the detection limit of the
method, the exposure on a 4 hr basis would be the same i.e. <0.05 f/mL.
Background fibre concentrations (static monitoring) were all less than 0.03 f/mL.
Results of TEM analysis, which are summarised in Table 13 show that chrysotile
fibres were found in all 3 brake bonding workshops and the gasket workshop but
only in one service garage,. The highest number of chrysotile fibres (using TEM)
was found in brake bonding workshops where up to 100% of sampled fibres were
identified as chrysotile.
Lower numbers of chrysotile fibres were found in samples from the gasket
workshop.
No chrysotile fibres were detected in the samples taken from 4 of the 5 service
garage workshops. This may indicate that no asbestos was present in the
atmosphere during sampling or that it was present at concentrations less than the
detection limit of the method. These samples were taken during removal and
replacement of asbestos parts e.g., changing drum and disc brakes. All mineral
fibres that were identified in the service garage for buses were amorphous silica
and forsterite which are products from heat affected chrysotile.
The results show that the TEM (asbestos) count was significantly higher than that
measured under light microscopy in 3 samples. This is due to the finer diameter
fibres counted using TEM, which are presumably caused by greater mechanical
breakage such as cutting and grinding. When diameter differences are taken into
account there is reasonable agreement between adjusted TEM counts and light
microscopy counts in nearly all samples.
40 Priority Existing Chemical Number 9
41
Chrysotile Asbestos
42 Priority Existing Chemical Number 9
43
Chrysotile Asbestos
Other Australian monitoring data
Atmospheric levels of asbestos have been monitored in several service garages by
occupational health and safety authorities in Western Australia (Table 13). In all
cases, the MFM method, including phase contrast light microscopy was used for
counting. Little information was provided on sampling details such as sampling
time and nature of the work being carried out. The majority of fibre
concentrations were < 1.0 fibres/mL, and all the most recent (1986-89) analyses
were <0.1 f/mL.
The data suggests that exposure levels have decreased over time. This may be a
result of the introduction of new work practices such as increased use of pre-
ground, ready-to-install parts, non-blowing methods of brake removal and use of
exhaust local ventilation.
Monitoring data were available from an Australian oil refinery for the removal
and replacement of asbestos gaskets. The standard NOHSC MFM method was
used except for sampling time. Sampling time was considerably less than 4 hours
for several samples. These results are tabulated in Table 14 at the 4 locations
designated as A, B, C and D. The results were < 0.1 fibres/mL in all cases.
Data were also available (provided by Richard Klinger Pty Ltd) from a limited
`test situation' study on airborne asbestos fibre concentrations during the
preparation of asbestos gaskets for use in typical engineering applications (i.e.
pipe flange sealing). Extensive work was conducted on the CAF sheeting
including cutting, hammering, drilling. Three gaskets were completed in the hour
test period. Personal exposures were < 0.05 f/mL (the detection limit) and a static
sample taken close to the work-piece was < 0.01 f/mL.
44 Priority Existing Chemical Number 9
45
Chrysotile Asbestos
Table 14 - Air monitoring results during processing of asbestos
gaskets
No. of Sampling Conc.
Location / Operation Comments
workers time (min) (f/mL)
Personal monitoring
4 250 < 0.01
A. handling CAF
gaskets
B. cutting gaskets 60 0.08 45 min. cutting with
a ball peen
hammer, 5 min.
with hand cutters,
remainder cleaning
up.
C. (i) scraping gaskets 1 13 0.07 3 successive
(ii) cutting gaskets 1 37 0.07 operations by one
(iii) cleaning up 1 12 0.1 worker
D. removal and 5 240 < 0.01 Actual time working
replacement of with gaskets was
gaskets significantly less
than 4 hours.
Static monitoring
C. at 3 locations 2-3 m 124 < 0.01
from cutting area
D. near cutting area 60 < 0.01
Note: Data for a limited test situation study on airborne asbestos fibre concentrations while preparing
asbestos gaskets for use in typical engineering applications, was provided by Richard Klinger.
46 Priority Existing Chemical Number 9
6.3 International exposure/monitoring data
6.3.1 Manufacture of asbestos products
Limited monitoring data for sites manufacturing friction materials and gaskets is
available in the literature. Information published in 1986 in the OSHA Report on
Occupational Exposure to Asbestos (Environmental Protection Agency, 1986) is
summarised in Table 15.
Table 15 - Atmospheric monitoring data for overseas manufacturing
sites
Product Activity Atmospheric Comments
Concentration
(f/mL)
Friction introducing raw 0.03 - 0.21 Monitoring of 15 employees
products chrysotile
(monitoring at
1 plant) involved in wet n.d. - 0.3 Monitoring of 28
mechanical operations employees. Most results
were < 0.2 f/mL.
involved in dry 0.07 - 1.7 One third of workers were
mechanical operations regularly exposed to levels
(e.g. grinding and > 0.2 f/mL.
machining)
Gaskets introducing raw 0.2 2 plants reported levels in
(monitoring at chrysotile excess of 0.75 f/mL.
3 plants)
involved in wet and dry < 0.2
mechanical operations
6.3.2 Exposure to asbestos in end-use products
Results from a number of air monitoring studies of garage workshops are
available in the scientific literature. Air monitoring studies were also available
for gasket modification and installation at oil refineries and chemical plants.
Removal and installation of friction materials
Monitoring data for atmospheric levels of asbestos in garage workshops are
summarised in the Table 16.
47
Chrysotile Asbestos
48 Priority Existing Chemical Number 9
49
Chrysotile Asbestos
50 Priority Existing Chemical Number 9
51
Chrysotile Asbestos
52 Priority Existing Chemical Number 9
The monitoring data includes results from studies conducted up to 25 years ago,
so these data may not be representative of current exposures in brake service
garages. However, the results provide some insight into the influence that control
measures have had on personal exposure. Higher results generally occurred in
the older studies during blowing and grinding operations. The more recent
studies (Sheehy et al., 1989 and Cooper et al., 1988) indicated lower exposures.
The MFM/PCM results indicate that exposure levels are generally <0.2 f/mL (no
grinding). In these studies control measures included enclosed devices or wet
cleaning.
In most cases monitoring was conducted only during the maintenance operation,
that is, only during the often very short period when fibres may be released.
These results are generally higher and not representative of exposure during 8 hr
shift or standard work periods. Therefore, the results should not be compared to
the occupational TWA exposure standard, where a minimum sampling duration
of 4 hours is required.
Several bulk samples of brake dust contained < 1% asbestos.
Removal and installation/modification of gaskets
The results of 3 studies carried out primarily to investigate the removal and
installation of gaskets are summarised in Table 17. The MFM results were
generally below 0.06 f/mL for monitoring of full workshifts during wet removal
of gaskets. Cheng and McDermott (1991) compared different methods of
removal of gaskets and found that the results were much higher during dry
removal of gaskets using a power sander (up to 1.4 f/mL). This study also
included monitoring during fabrication (cutting) of sheet gaskets (CAF), where
the maximum time-weighted average exposure was 0.017 f/mL.
6.4 Summary
Workers may be exposed to chrysotile during the manufacture and use of
chrysotile products. Exposure is most likely to occur during the handling of raw
chrysotile during manufacture and installation/modification and replacement of
the products in the aftermarket.
Air monitoring data were analysed from various sources including, applicants
(Bendix Mintex, Richard Klinger), the automotive aftermarket survey (carried out
by NICNAS), air monitoring in service garages in Western Australia and
international exposure data in garage workshops and industries involved in the
removal and replacement of asbestos friction products and gaskets. Results from
these studies indicate that over the past 10 years, samples were less than 1 f/mL
(NOHSC national exposure standard for chrysotile6).
Raw chrysotile is used by Bendix Mintex in the manufacture of friction products.
Air monitoring data was provided for the period 1992 to 1997. During this period
more than 80% of personal samples (all fibres) were < 0.1 f/mL and only two
samples were > 0.5 f/mL. There are no other manufacturers of asbestos friction
6
Where exposure to other asbestos fibres is possible, the NOHSC exposure standard is 0.1 f/mL
(NOHSC 1995d).
53
Chrysotile Asbestos
54 Priority Existing Chemical Number 9
products in Australia, however information available to NICNAS indicates that at
least 10 other companies import asbestos friction products.
At Richard Klinger (Perth site), raw chrysotile is used in the manufacture of CAF
sheets for production of gaskets. Air monitoring data (between 1991 to 1996)
showed that during raw material handling, approximately 60% of personal
samples (all fibres) were <0.1 f/mL and only one sample was > 0.5 f/mL (i.e. 0.8
f/mL). Richard Klinger is the only gasket manufacturer in Australia using raw
chrysotile, however there are a number (at least 5 companies) of
manufacturers/processors (using CAF sheeting starting material) of asbestos
gaskets.
At Richard Klinger (Melbourne site), processing (cutting and stamping) of
gaskets is undertaken, however no sanding or grinding occurs. Air monitoring
samples for both personal and static samples for the years 1989, 1991, 1993 and
1995 were < 0.05 f/mL. Although only a few samples were undertaken at
specified locations, Richard Klinger indicate that they represent highest exposure
potential to CAF sheeting. In addition, Richard Klinger have stated that it would
be incorrect to assume that this data is representative of other manufacturers of
CAF gaskets as potential chrysotile exposure levels are related to the grade of
CAF (i.e., degree of fibre encapsulation in the CAF matrix and amount of a free
surface layer asbestos7).
The third applicant, Vivacity Engineering stated that they had not conducted any
air monitoring studies and that they intended phasing out all use of chrysotile
during 1997, although this had not occurred as at August 1998.
Asbestos fibres may be released during replacement of friction products and
gaskets in vehicles. Many service garages around Australia carry out brake and
clutch repair work and therefore workers may be exposed to friable asbestos.
Results of the NICNAS air monitoring studies in an automotive aftermarket
industry indicate that personal and static short-term exposures were < 0.05 and <
0.03 f/mL respectively. These levels may have been lower if the sampling
duration was longer. For comparison with TWA occupational exposure
standards, the preferable minimum total sampling duration is 4hr.
Monitoring data from Western Australia service garages carried out in the last 10
years indicate exposures to be < 0.1 f/mL. These results also show that recent
exposure levels appear to be lower than in the past.
International monitoring results in service garages indicate that exposure levels
are generally < 0.2 f/mL (no grinding). The data includes studies conducted up to
25 years ago and indicates that exposure levels have decreased over time.
Decreases in exposure levels are likely to be due to implementation of better
engineering controls and good work practices (e.g., use of compressed air to blow
dust from brake parts is prohibited and the use of grinders has diminished) during
brake and clutch servicing.
In the brake bonding industry worn brake pads and clutch facings are stripped
from their metal supports and replaced with new pads and linings. The NICNAS
automotive aftermarket survey indicated that exposure to chrysotile was highest
7
Richard Klinger have indicated that the CAF sheeting they manufacture is a high grade product
(i.e., maximum encapsulation and low dust residue).
55
Chrysotile Asbestos
during grinding of brake shoes and cutting of brake linings. The highest personal
monitoring result obtained was 0.16 f/mL, during cutting of brake shoes. This
exposure level could be reduced with improved local exhaust ventilation.
In the gasket industry, CAF sheeting is cut to size and is modified by stamping,
sawing and drilling at several workshops in Australia. Limited monitoring data is
available in this area. Results of short-term monitoring data in 3 Australian
studies indicate that personal exposures were 0.08 f/mL and static exposures <
0.01 f/mL. Personal exposure in an overseas study was < 0.02 f/mL (TWA)
during cutting of CAF.
A review of 3 international studies on occupational exposure to asbestos during
removal and installation of gaskets showed that the highest exposure levels were
during dry removal of gaskets (up to 1.4 f/mL). During wet removal of gaskets
exposure levels were below 0.06 f/mL.
56 Priority Existing Chemical Number 9
7. Health Effects and Risk
Characterisation
The human health effects from exposure to asbestos, including chrysotile, are
well documented. There are many reviews available that give detailed
information on the pathology and/or epidemiology of asbestos-related diseases.
These include: Doll and Peto (1985); International Programme on Chemical
Safety (IPCS) Environmental Health Criteria 53 (1986); IPCS Environmental
Health Criteria 203 (1998); Mossman and Gee (1989); Roggli (1990); Selikoff
(1990); Hughes and Weill (1991); McDonald and McDonald (1991); Liddell
(1991 & 1997); Stayner et al (1996); Smith and Wright (1996). The data
presented here is not intended to be a detailed review of the literature, but is a
summary of the pertinent data on the health effects and risk estimates for
exposures to asbestos/chrysotile. In addition, controversial issues and
uncertainties associated with the assessment of hazard and risk are highlighted.
7.1 Historical overview
Since the turn of the century, asbestos has been recognised as an occupational
health hazard. All forms of asbestos have been linked with asbestosis, lung
cancer and mesothelioma in humans. Other malignancies (including
gastrointestinal cancer) have also been associated with asbestos exposure,
however, the epidemiological evidence is inconclusive.
Mining and industrial use of asbestos goes back to the late 19th century.
Asbestosis was first identified in the 1920s. Public awareness that lung tumours
were causally related to asbestos was first noted in an epidemiological study of
chrysotile textile workers in Rochdale, UK in 1955 (Doll, 1955). Malignant
mesotheliomas were first described in the northwestern Cape region of South
Africa in miners exposed to crocidolite (Wagner et al., 1960).
7.1.1 Classification of health effects
All forms of asbestos, including chrysotile, are classified by regulatory authorities
as carcinogenic to humans.
The International Agency for Research on Cancer (IARC) classify all forms of
asbestos under carcinogen Category 1 (IARC, 1987). NOHSC classify chrysotile
as a Category 1 carcinogen (Risk phrase 45) . This classification is consistent
with that of the EU (EEC Council Directive 67/548/EEC). In addition, according
to NOHSC (NOHSC, 1994c), chrysotile products containing > 0.1% chrysotile
should also be classified as carcinogenic (Category 1).
57
Chrysotile Asbestos
7.2 Human health effects from exposure to asbestos
7.2.1 Asbestosis
All forms of asbestos may cause asbestosis. Asbestosis was the first asbestos-
related lung disease to be recognised. It is defined as diffuse interstitial fibrosis
of the lungs resulting from exposure to asbestos dust. It is this scarring of the
lungs which reduces their elasticity and function resulting in breathlessness. It
can appear and progress many years after the termination of exposure.
Epidemiological data indicate that the disease incidence rate increases and
becomes more severe with increasing dust levels and duration of exposure (Weill,
1994).
7.2.2 Lung cancer
Lung cancer has been shown to be caused by all types of asbestos fibre. Lung
cancer has been responsible for the largest number of deaths attributable to
occupational exposure to all principal commercial asbestos forms i.e. chrysotile,
amosite and crocidolite. An increased incidence of lung cancer has been
documented among workers involved in asbestos mining and milling and in the
manufacturing and use of a variety of asbestos products. The average latency
period of the disease (from the first exposure to asbestos) ranges from 20 to 30
years.
Combined exposure to asbestos and cigarette smoke increases the risk of lung
cancer. Together they act synergistically and the combined risk is much greater
than the individual risks for exposure to asbestos or for smoking (IPCS, 1996).
Lung cancers caused by asbestos are clinically indistinguishable from those
caused by cigarette smoking.
IPCS (1998) concluded that based on available data in miners and millers, there is
an interaction between tobacco smoke and chrysotile in the induction of lung
cancer which appears to be less than multiplicative.
The question of whether asbestos-induced lung cancer can develop in the absence
of asbestosis has been the subject of intense debate. The issue has been discussed
in detail in several reviews including Becklake (1991); HEI-AR (1991) and
Meldrum (1996).
Autopsy investigations in some workers have shown that asbestos-induced lung
cancer is seen in association with pulmonary fibrosis (Newhouse et al., 1985;
Kipen et al., 1987; Wagner et al., 1988). Hughes and Weill (1991) also reported
excess risk of lung cancer being restricted to workers with x-ray film evidence of
asbestosis. Meldrum (1996) states that there is sufficient evidence to demonstrate
an association between asbestosis and lung cancer. Evidence includes similarities
in dose-response relationships, latency periods for development and similar
dependencies on fibre length and type. These findings are consistent with the
view that asbestos is a lung carcinogen by virtue of its fibrogenicity.
On the other hand, a number of studies have suggested that lung cancer may be
caused by asbestos in the absence of asbestosis (Anttila et al., 1993; Hillerdal,
1994; Wilkinson et al., 1995; Egilman & Reinert, 1996).
58 Priority Existing Chemical Number 9
Abraham (1994) and Roggli et al. (1994) argue that there is insufficient evidence
to determine the association between these two diseases. Should there be a causal
relationship between asbestosis and asbestos-induced lung cancer, this would
support a `threshold for effect' hypothesis for asbestos induced lung cancer.
7.2.3 Mesothelioma
Pulmonary mesothelioma is a primary malignant tumour of the mesothelial
surfaces, generally affecting the pleura and less commonly the peritoneum.
Mesothelioma has been associated with occupational exposure to chrysotile,
amosite and crocidolite. The latency period is generally between 35 and 40 years.
In almost all cases prognosis is extremely poor, with the survival rate generally
being less than 2 years following diagnosis.
IPCS (1996) reports that although up to 90% of pleural mesothelioma cases have
been attributed to asbestos, no evidence has been advanced to delineate the
effects of smoking on this disease.
The Australia Mesothelioma Surveillance (AMS) Program
The AMS Program began on 1 January 1980, to monitor the incidence of the
disease and to explore occupational and other associations with mesothelioma. A
system of formal voluntary notifications of mesothelioma cases was introduced.
Information collected included full occupational and environmental history,
diagnosis by a pathology panel and assessment of lung fibre content.
From January 1986, a less detailed notification system has operated, the
Australian Mesothelioma Register, and is a continuation of the AMS Program
(Leigh et al., 1997). This includes a short questionnaire history, followed up by
mail. Only histologically confirmed cases are accepted but there is no
confirmation of the diagnosis by a pathology panel. Incident cases from 1945 to
end 1996 totaled 4585 notifications and a continuing upward trend over time is
clearly evident (Figure 6). There has been an increase in both male and female
rates of mesothelioma cases, however the male rate is over 7 times the female
rate. Leigh et al. (1997) reports that these are the highest reported rates in the
world and that incidence is now similar to Hodgkins lymphoma or liver cancer
and the mortality greater than that of cervical cancer.
Occupation/industry classification of the mesothelioma cases on the register are
based on the Australian Bureau of Statistics `Industry and Occupation Codes'.
The percentage of overall cases of mesothelioma (January 1986 to March 1995)
according to exposure category are; repair and maintenance of asbestos materials
(13%), shipbuilding (3%), asbestos cement production (4%), railways (3%),
power stations (3%), boilermaking (3%), mining (Wittenoom) (5%), wharf labour
(2%), para-occupational, hobby, environmental (4%), carpentry (4%), building
(6%), navy (3%), plumbing (2%), brake linings (manufacture/repair) (2%) and
combinations of the above (multiple) (12%) (Leigh et al., 1997). Leigh (1994)
reported that the pattern of exposure is shifting away from the older traditional
industries towards product, domestic and environmental exposure. An analysis of
16 years data in 1996 by Yeung et al (1997) showed more cases (on a number of
cases basis) in more recent years in the asbestos user industries and from
occupations such as plumbers, carpenters, machinists and car mechanics.
59
Chrysotile Asbestos
60 Priority Existing Chemical Number 9
In the AMS Program, the potency for mesothelioma for different asbestos types
has been investigated. Analysis of some 1,000 cases indicated that appoximately
one third of cases were primary asbestos workers, while a further third came into
contact with asbestos in the coarse of their work and for the remaining third, there
was either no available information or they did not have a history of occupational
exposure to asbestos. Almost all of the occupationally exposed cases had been
exposed to mixed asbestos types (combinations of crocidolite, amosite or
chrysotile) with the exception being those from Wittenoom (crocidolite only), but
these cases only contributed 7 % of all cases in Australia (Ferguson et al., 1987).
Data were analysed on a case-referent basis, to relate relative risks of
mesothelioma to dose of fibre, as measured both by lung content and estimated
airborne exposure. Multivariate analysis of Australian cases found a dose
response relationship for lung fibre content of crocidolite, amosite and chrysotile
and the development of mesothelioma. Either a multiplicative or additive model
could be used to fit the relative risk/dose coefficients for the various asbestos
types. A progressive increase in relative risk with increasing fibre content was
reported for all fibres (Rogers et al, 1991; Leigh, 1994). Tests for trend were
highly significant in all cases.
Further review of the information contained in the case histories, provided
evidence that the effects of increased lung clearance of chrysotile (see section
7.5) reduced considerably the relative risk of mesothelioma compared with the
risk associated with amphiboles. Using an additive risk model adjusting in terms
of relative airborne exposure levels, the risk coefficients8 for each fibre type were
9.1 for crocidolite, 5.2 for amosite and 0.013-0.006 for chrysotile (Rogers et al.,
1994). It was concluded that although the evidence shows that crocidolite,
amosite and chrysotile can all cause mesothelioma, chrysotile is less potent in this
regard (Leigh, 1994). A review of this work and a comparison of findings from
other epidemiological studies was presented to NOHSC (Rogers and Leigh,
1991).
7.2.4 Other malignancies
In some cohorts of workers occupationally exposed to asbestos (Hillerdal et al.,
1983; Doll & Peto, 1987) cancer of the larynx, oropharynx, and upper and lower
digestive tract have been reported to be increased. The excess risk for these
tumour types appears to be small.
7.3 Human health effects from exposure to chrysotile
Chrysotile can cause asbestosis, lung cancer and mesothelioma. In most groups
of workers, lung cancer is the predominant cause of death related to chrysotile
exposure. There is increasing consensus that the hazards of the different forms of
asbestos are different, with chrysotile less hazardous than amphiboles (see section
7.5). Therefore, the data on chrysotile needs to be considered in isolation to, and
in conjunction with, data on other forms of asbestos. In addition, it has been
argued that fibre size also impacts on the degree of hazard.
8
This figure is based on lung fibre levels in humans, whereas the relative potency estimate
reported in section 7.5 of this report was based on clearance data obtained from animal studies.
Both estimates have been critiqued.
61
Chrysotile Asbestos
The major heat degradation product of chrysotile (of relevance to applications
where chrysotile may be heated to high temperatures i.e., in its use in friction
products) is forsterite. Forsterite or other `olivine' minerals have been shown to
be non fibrogenic and non-carcinogenic in animal studies and do not appear to
cause fibrosis/silicosis in humans (Anderson 1995; Jones et al., 1996).
7.3.1 Asbestosis
Chrysotile has been shown to cause asbestosis. There is some evidence
indicating that chrysotile is less potent than amphiboles in causing asbestosis
(Wagner et al., 1988; Becklake, 1991). There is also evidence to suggest that fibre
size may influence the degree of hazard. For example, the rate of radiologic
asbestosis in Quebec textile plant workers was greater than in Quebec miners and
millers, possibly due to differences in fibre size.
7.3.2 Lung cancer
Exposure to chrysotile is associated with an excess risk of lung cancer. Table 18
summarises the results for mortality from lung cancer (and mesothelioma) from a
recent update of cohorts predominantly exposed to chrysotile.
In all but one study, mortality from lung cancer was greater than expected,
however this was only statistically significant in 50% of studies. In the studies
that included information on tobacco habits, the observed excesses of lung cancer
mortality did not appear to be related to differences in cigarette consumption.
Studies indicate that there are marked differences in the levels of risk for the
various industries i.e., greater risk in textile manufacturing compared to mining,
milling and friction product manufacture. The most common reason suggested
for these differences is fibre size, as longer fibres were generally used in the
textile industry (Doll & Peto, 1985).
The carcinogenic potency of chrysotile compared to the amphiboles has been
increasingly debated in the literature. Several authors have also concluded that
there is sufficient epidemiological evidence to show that chrysotile, at
comparable exposures, is less potent than amphiboles in the induction of lung
cancer. Across-study comparisons have been conducted to examine the
relationship of fibre type and risk of lung cancer. However, such comparisons are
limited as exposure levels and other differences cannot be taken into account and
most occupational scenarios involve exposure to mixed asbestos fibres.
Therefore, the comparative risks for different fibre types cannot be quantified.
Table 19 is a summary of lung cancer risk in industrial cohorts by industry
segment and fibre type.
The studies and results are discussed in more detail by (Hughes, 1991), where
references for individual studies are provided. Hughes concluded that the above
epidemiological studies demonstrate increased lung cancer risk among past
asbestos-exposed workers. The studies indicate that lung cancer risk associated
with chrysotile exposure is likely to be lower than from exposure to amphiboles
or mixed fibres, except in the textile industry. The information also indicates that
where exposure is primarily to chrysotile, the potential risk is related to industry
type.
62 Priority Existing Chemical Number 9
In contrast, Stayner et al. (1996) stated that the results of the textile industry do
not support the theory that chrysotile is less potent than amphiboles in inducing
lung cancer. They concluded that variations in risk are more related to industry
type rather than fibre type and that there is little evidence to indicate a lower risk
of lung cancer from exposure to chrysotile. From the available human and
animal data, Nicholson and Landrigan (1994) concluded that chrysotile is as
potent a lung carcinogen as any other variety of asbestos.
Table 18 - Summary of epidemiological cohort studies of workers
exposed predominantly to chrysotile
Industry Lung cancer Mesothelioma Study
deaths cases
Observed Expected Observed Deaths
No. %
a
1 0.6 (Acheson et al., 1982)
Gas masks 6 4.8
Textiles, friction 21 6.7* 2 0 (Cheng & Kong, 1992)
materials and
cement
Textiles 126 64.0* 2 0.2 (Dement et al., 1994)
Electrical conduit 6 3.7 1 1.0 (Finkelstein, 1989)
pipe
b
1.0-1.9 (Finkelstein, 1989)
Automotive 11 7.9 1-2
Cement 70 53.2 1 ... (Hughes et al., 1987)
c
manufacturing
15.6a*
8 asbestos (Huilan & Zhiming,
65 2 0.4
factories 1993)
(McDonald et al.,
Friction products 73 49.1* 0 0
1984)
Mining and (McDonald et al.,
518 389.7* 28 0.4
millingd 1980) and (McDonald
et al., 1993)d
Mining 22 19.9 2 0.5 (Piolatto et al., 1990)
Paper and 4 4.3 0 0 (Weiss, 1977)
millboard
TOTAL 922 618.9 41 0.3
Table adapted from (Stayner et al., 1996)
a
Expected number for cancer of the lung and pleura combined.
b
One or two cases of mesothelioma were reported. Only one was included in the totals.
c
Results are for workers exposed only to chrysotile from one of two plants studied. The
total number of deaths was not reported: thus the percentage of mesothelioma deaths
could not be estimated.
d
Observed and expected numbers exclude observations from the asbestos factory.
* Significantly different from the observed number, P<.05 (two tailed).
This percentage is for all studies combined.
63
Chrysotile Asbestos
Table 19 - Lung cancer risk by industry segment and fibre type
Chrysotilea Mixed Amphiboles
Industry Obs Exp Obs/ Obs Exp Obs/ Ob Exp Obs/
Exp s Exp
Segment Exp
Mining/milling 239 192.7 1.24 91 34.5 2.64
Gas mask 6 4.8 1.25 33 15.8 2.09
manufacturing
Friction 161 131.4 1.23
productsb
Insulation 397 93.7 4.24 84 17.5 4.80
Assorted 4 4.3 0.93 77 72.4 2.71
manufacturing
Asbestos 58 56.3 1.03 351 225.1 1.56
cement
Textiles 94 55.6 1.69 342 188.9 1.81
Total 562 445.1 1.26 1167 536.1 2.18 208 67.8 3.07
Table source: Hughes (1991)
Obs = Observed
Exp = Expected
a
exclusively or predominantly chrysotile
b
combined results from studies by McDonald et al. (1983) and Newhouse and Sullivan
(1989)
7.3.3 Mesothelioma
Chrysotile has been shown to be associated with an increased risk of
mesothelioma in humans. It is not possible to compare the number of observed to
expected cases as mesothelioma is such a rare disease in the general population.
Stayner et al. (1996) compared the percentage of deaths due to mesothelioma to
the background percentages in the United States to demonstrate the association
between chrysotile and mesothelioma (see Table 18).
Based on epidemiological evidence some investigators are of the opinion that for
a given exposure, the risk of developing mesothelioma is greater with amphiboles
(primarily crocidolite) than chrysotile (Hughes & Weill, 1986; Leigh, 1994;
Rogers et al 1994; Meldrum, 1996; Stayner et al., 1996).
In contrast, other investigators have concluded that chrysotile is a major cause of
mesothelioma in humans and has a similar potency to amphiboles. The US EPA
(US EPA, 1989), in its quantitative assessment of mesothelioma risk, concluded
that epidemiological and animal evidence did not conclusively establish
differences in mesothelioma hazard for the various asbestos fibre types and as
such all asbestos fibres should be regarded as exhibiting similar carcinogenic
potency. Smith & Wright (1996) reviewed the data from the asbestos cohorts
ranked according to the ratio of pleural mesotheliomas per 1,000 deaths, and
found chrysotile to be the primary asbestos type for at least 2 of the 10 top-
ranking cohorts. The authors concluded that chrysotile is of similar potency to
amphiboles. Similarly, Huncharek (1994) concluded that for mesothelioma (as
for lung cancer) the differences for carcinogenic potential appear to be more
64 Priority Existing Chemical Number 9
related to fibre size than fibre type. In support of this were findings in an
Australian study, where a significant dose-response effect for short chrysotile
fibres was independent of the presence of long amosite and long crocidolite
fibres, based on lung fibre content (Leigh, 1994).
7.3.4 Epidemiological studies on friction product manufacture
There are 3 major studies relating to the mortality and cancer incidence of
employees working in the manufacture of chrysotile friction products (Berry &
Newhouse, 1983; McDonald et al., 1984; Finkelstein, 1989).
The mortality of over 13,000 workers at a UK factory producing friction products
has been reported. The initial study analysed mortality data for the period 1941-
1979 (Berry & Newhouse, 1983). The study was then extended to include data
to1986 (Newhouse & Sullivan, 1989). During this period only chrysotile was
used in the factory, with the exception of 2 periods before 1945 when crocidolite
was used. The study found that there was no detectable excess of deaths due to
lung cancer, gastrointestinal cancer or other cancers. There were 13
mesothelioma cases, however, eleven of these subjects had known contact with
crocidolite. Of the 2 remaining mesothelioma cases, diagnosis was uncertain for
one case and the occupational history was not well established for the other.
From 1931-1950 exposures were 5-20 f/mL in certain areas, after 1950 they were
<5 f/mL and since 1970 levels were <1 f/mL (Newhouse & Sullivan, 1989). The
SMR was 106, but was not considered statistically significant (Berry &
Newhouse, 1983).
A study by McDonald et al. (1984) investigated mortality due to lung cancer,
mesothelioma and asbestosis in three US factories manufacturing friction
products and packings. The cohort comprised 3641 men employed between
1938-1958. During the 1930s exposures for most processes were 1-5 mpcf
(millions of particles per cubic foot) and >10 mpcf during dry mould mixing. By
the 1960s most exposures were <0.5 mpcf. A significant excess of deaths
(reference was to mortality rates for Connecticut) due to respiratory cancer was
observed however this was not related to duration of employment. No cases of
mesothelioma were reported. There was limited evidence of an increase in risk of
lung cancer with increasing exposure. However the SMR for lung cancer was
noted in workers with less than one year of service.
A study by Finkelstein, (1989) investigated mortality rates among 1657
employees at two Ontario factories manufacturing chrysotile friction materials.
The study population consisted of workers employed for at least 12 months after
1 January 1950. The study showed a significant increase in mortality from
laryngeal cancer and lung cancer. No increase in mortality was noted from
gastrointestinal cancer or from non-malignant respiratory disease. One or two
deaths may have been due to pleural mesothelioma. Case-control analysis
demonstrated a lack of association between the risk of death from laryngeal or
lung cancer and the duration of employment or employment in departments
where chrysotile had been used. The author also notes that cigarette smoking is a
risk factor for laryngeal cancer and lung cancer, and therefore, increased risk may
be in part attributable to differences in smoking habits.
In reviewing the above studies, Berry (1994) concluded that the risk from
working in the manufacture of chrysotile friction materials are small compared to
risks associated with working with chrysotile in the textile industry.
65
Chrysotile Asbestos
7.3.5 Case reports of mesothelioma in car mechanics
In Germany, Woitowitz and Rodelsperger (1991) reported that out of 174
identified cases of mesothelioma, 14 were in car mechanics. Eleven of these
cases were workers who moved from this occupation to others where asbestos
exposure was known. Only 3 had remained as car mechanics for the duration of
their working life. The authors concluded that there was an increased incidence
of mesothelioma among car mechanics. This finding was refuted by Wong
(1992) in a letter to the Editor, which provided further statistical interpretation of
these results together with a review of similar studies carried out in the US, which
indicated no increased mesothelioma risk for garage mechanics. In response, the
authors conducted a further study on a larger group of mesothelioma cases (324
cases), which included 16 cases listed as car mechanics. On detailed
examination, only 6 cases had definate exposure to asbestos (during brake repair)
and the authors concluded that there was no evidence that car mechanics are
exposed to an increased risk of mesothelioma, even if they are involved in brake
repair work (Woitowitz and Rodelsperger, 1994).
Of 413 cases of mesothelioma notified to the UK Mesothelioma Register during
the period 1967 to 1968, only 1 case was listed as a motor mechanic (Greenburg
and Davies 1974). A review of the period 1967 ?1992 from the UK register,
indicated a total of 11,492 cases, in which there was no mention of garage or
motor mechanics as being in groups with an increased incidence of mesothelioma
(Rogers 1998). A more detailed analysis of the occupations associated with these
cases (reported at the Inhaled Particles Conference in Oxford, UK in 1996)
reported that during this period, motor mechanics had a mesothelioma incidence
rate of approximately 50% of the general (background) UK population (Rogers
1998).
An analysis of the Australian Mesothelioma Surveillance Programme (AMS) and
Register for the period 1979-1985 indicated that 7 cases out of a total of 858
cases were recorded in car mechanics who had handled asbestos friction products
(Ferguson et al., 1987). Out of 2119 mesothelioma cases registered (with a
response to history) for the period 1986-1995, 46 cases were listed for the
category `brake lining - manufacture/repair', 40 of which were recorded in car
mechanics, of which 37 were exposed to asbestos in this occupation only9 (Leigh
et al., 1997; Rogers et al. 1997). Overall the numbers indicate a slight increase of
around 1-2 cases per year, which is roughly proportional to the growth rate of all
mesothelioma cases in Australia (Rogers, 1998).
7.4 Animal data
Results from animal studies reflect the known human health effects of asbestos.
IARC (1987) reports that asbestos has been tested for carcinogenicity by
inhalation in rats, by intrapleural administration in rats and hamsters, by
intraperitoneal injection in mice, rats and hamsters and by oral administration in
rats and hamsters. Chrysotile, crocidolite, amosite, anthophyllite and tremolite
produced mesotheliomas and lung carcinomas in rats after inhalation and
mesotheliomas following intrapleural administration. Chrysotile, crocidolite,
9
Bendix Mintex have questioned this job description, as they state that most brake work is carried
out by mechanics who may be exposed to asbestos in other (non-friction material) products e.g.
gaskets, body fillers and historically, tremolite talc (used in puncture repair).
66 Priority Existing Chemical Number 9
amosite and anthophyllite induced mesotheliomas in hamsters following
intrapleural administration. Intraperitoneal administration of chrysotile,
crocidolite and amosite induced peritoneal tumours, including mesotheliomas, in
mice and rats and abdominal tumours in rats (administered crocidolite).
Animal studies have been useful in studying the association between lung cancer
and asbestosis and the time course of disease development following exposure.
Studies have shown that fibre-induced lung cancer is preceded by the
development of pulmonary fibrosis and that exposures which are insufficient to
cause asbestosis do not lead to an increase in lung tumour incidence (Meldrum,
1996, Davis and Cowie, 1990). However, available inhalation studies are
considered inadequate for investigating dose-response relationships and no study
has clearly identified a NOAEL (no adverse effect level) for any of the endpoints.
7.5 The relationship between fibre type and size to carcinogenicity
Although all forms of asbestos are hazardous and have been shown to cause
asbestosis, lung cancer and mesothelioma, there is accumulating evidence to
indicate that the degree of hazard (pathogenicity) is intrinsically related to:
? fibre type; and
? fibre size distribution.
Several authors have concluded that there is sufficient evidence to demonstrate
that chrysotile is less hazardous than amphiboles (McDonald & McDonald, 1987;
Hughes, 1991; Churg, 1994; Meldrum, 1996). With respect to mesothelioma,
Leigh (1994) concluded that chrysotile is some 14 times less potent in this
regard.*
As commercial chrysotile may contain low levels of tremolite, it has been
suggested that tremolite may be the cause of mesotheliomas in populations
exposed primarily to chrysotile (Churg & Harley, 1984; Weill & Hughes, 1988;
McConnochie et al., 1989). However, Begin et al. (1992) reported that in Quebec,
mesothelioma rates are as high in the `Asbestos region' as the `Thetford mines
region', despite much lower tremolite contamination of chrysotile in the former
region. In addition, mesotheliomas have been reported in animal studies from
exposure to `pure' chrysotile ( Wagner et al., 1974; Frank et al., 1997). In
conclusion, the tremolite issue is largely unresolved and has been considered by
many as academic, in that tremolite is an impurity in most commercial chrysotile
samples.
IPCS concludes that dose-response information is needed for animal studies for
various asbestos fibre types in order to evaluate the differential risks from
different fibre types (IPCS, 1998).
The predominant reason proposed for a lower potency for chrysotile, compared to
other asbestos fibres, is the shorter residence time of chrysotile fibres in the lung.
This could be a result of:
? chrysotile being chemically unstable in the lung and the leaching of
magnesium, eventually leading to dissolution of the fibre; and
*This figure is based on clearance data obtained from animal studies, whereas the relative potency estimates
reported in section 7.2.3 of this report were based on human lung fibre levels. Both estimates have been
critiqued.
67
Chrysotile Asbestos
? chrysotile rapidly fragmenting into very short fibrils that are easily
phagocytised and removed from the lung (Churg, 1994).
It has also been postulated that due to their shape, inhaled chrysotile fibres do not
reach the parenchyma but instead are trapped at large airway bifurcations,
whereas amphiboles (due to their straight shape) are carried in the airstream into
the periphery of the lung (Mossman & Gee, 1989; Churg, 1994). However,
animal studies have shown extensive chrysotile deposition in the lungs and some
reports have concluded that deposition fractions of amphiboles and chrysotile
fibres are similar (Churg, 1994).
There has been intense debate about which property (fibre type or fibre size) has
the greatest impact on potency. For example, Nicholson & Landrigan (1994) and
Smith & Wright (1996) examined the evidence from epidemiological and animal
studies published in the literature and concluded that, in general, the differences
between studies using the same fibre type exceed those that exist between using
different fibres. There is however good evidence to indicate that long fibres are
more hazardous than short fibres (Stanton et al., 1981; Smith & Wright, 1996).
Relative risks for mesothelioma, in particular, have been shown to be statistically
higher for chrysotile, crocidolite and total amphibole fibres > 10 祄 than for
risks associated with fibres < 10 祄 (Leigh, 1994).
It is generally accepted that the fibre dimensions that correlate most strongly with
increased lung tumour incidence are fibres that measure > 5 祄 long (length) and
< 3 祄 wide (diameter) (Spurney 1995). However high correlations have been
seen in other size ranges, such as > 8祄 long and <0.25 wide and > 4 祄 long
and < 1.5 祄 wide (Stanton et al. 1981). Dimensions of asbestos and non-
asbestos fibres can be found in Table 35 (Section 11). In addition, it is generally
assumed that the carcinogenic effect of fibres decreases rapidly when the ratio of
length to diameter (aspect ratio) falls below 3 (EC, 1997).
IPCS (1998) concluded that the significance of physical and chemical properties
(e.g. fibre dimension, surface properties) of fibres and their biopersistence in the
lung in relation to their biological and pathogenic effects needs further
elucidation.
7.6 Characterisation of lung cancer risk from asbestos exposure
Several risk estimates for occupational exposure to chrysotile have been
published in the literature. Because lung cancer is the overriding risk from
chrysotile exposure, most estimates are based on this effect. Table 20
summarises estimates of lung cancer risk by industry and fibre type for different
cohort studies (Stayner et al., 1996). These risk estimates have been based on a
linear, non-threshold model, where the slope of the linear dose-response
relationship (expressed as the excess relative risk of lung cancer per unit of
cumulative exposure (fibre.year/mLs) is indicative of the level of risk.
The risk estimates indicate that there is an increased risk with increasing exposure
in all industries. The rate at which the risk of lung cancer increases with
cumulative exposure (the slope of the line) appears to vary significantly for
different industries. Textile manufacture produces the highest risk of lung cancer,
with lower risks for production of cement products, friction materials and
68 Priority Existing Chemical Number 9
Table 20 - Estimates of lung cancer risk from exposure to chrysotile
in different industries
Excess relative
Study Industry Fibre type
risk
per fibre.year/mL
Dement et al., 1994 Textiles Chrysotile 0.031
0.017a
McDonald et al., 1983 Mainly textiles Chrysotile,
amosite, &
crocidolite
0.015b
Peto et al., 1985 Textiles Chrysotile &
crocidolite
a,c
McDonald et al., 1993 Mining and milling Chrysotile 0.0006
0.0071a
Hughes et al., 1987 Cement products Chrysotile
0.0076b
Chrysotile &
crocidolite
Berry & Newhouse, 1983 Friction products Chrysotile 0.00058
a
McDonald et al., 1984 Friction products Chrysotile 0.00053
Table adapted from Stayner et al., (1996)
a
A conversion factor of 3 fibres/cc being equivalent to 1 million particles per cubic foot
was assumed.
b
Data are based on results for workers employed after 1951.
c
Slope was estimated by fitting a linear relative risk Poisson regression model to the
standardised mortality ratio results reported by (McDonald et al., 1986).
chrysotile mining. The reasons for the variation in risk between industries are not
clear, however, it has been postulated that differences may be partly attributable
to differences in the airborne fibre size distributions in the industries, and also to
inaccuracies in the reported exposure estimates (Meldrum, 1996). A study of fibre
morphology by (Dement & Wallingford, 1990) indicated that airborne asbestos
fibres in the textile industry were longer than in the cement pipe or friction
products industries. Another possible explanation is that the processing of
chrysotile could change fibre sizes and morphology.
Based on the weight of evidence, different forms of asbestos appear to possess
different degrees of hazard (see section 7.5). Several investigators have also
concluded that there is sufficient evidence to show that the level of risk of lung
cancer for chrysotile exposure varies between industry sectors (Doll & Peto,
1985; Nicholson, 1991; Meldrum, 1996).
7.6.1 Risks in the friction product industry
The industry of most relevance to chrysotile usage in Australia is the manufacture
of friction products. Risk estimates for this industry are available from two
studies (Berry & Newhouse, 1983 and McDonald et al., 1984). Similar risk
estimates (based on a linear extrapolation methodology) of approximately 0.0006
(excess relative risk per fibre.year/mL) were obtained for these studies (see Table
20).
NOHSC reviewed the available epidemiological data on the risk of lung cancer
associated with chrysotile (NOHSC, 1995a). It was decided that risk estimates in
Australia should be based on data from mining and friction product
69
Chrysotile Asbestos
manufacturing industries. For this purpose the UK/US OSHA additive relative
risk model (RR = 1 + excess relative risk) was used. Using the excess relative
risk10 (0.0006 fibre.year/mL) obtained from McDonald et al (1993) and Berry &
Newhouse (1983) data, estimates were derived for lung cancer risk at different
chrysotile exposure levels (see Table 21).
Table 21 - Estimated risk of lung cancer at various levels of exposure
to chrysotile
Excess risk1
Exposure
(yearly average fibre/mL) (per 100,000 persons exposed)
NOHSC US OSHA US NIOSH
1 173 2880 5760
0.5 86 1440 2880
0.1 17 288 576
1
Excess risk = Risk coefficient x lifetime exposure (yrs) x average exposure level (f/mL) x
background risk*
[*A cumulative background risk for lung cancer in the male population was used in these
calculations (i.e., 7,200/100,000 assuming mixed smoking habits)].
NOHSC estimated that the number of lung cancers per 1000 workers lifetime
(assuming mixed smoking habits and 40 years continuous exposure) expected in
the Australian friction products industry is 1-2 cases at 1 f/mL, 1 case at 0.5 f/mL
and 0.2 case at 0.1 f/mL (NOHSC, 1995a).
There has been some debate over the choice of the risk coefficient for the
calculation of excess risk. The US OSHA lifetime excess risk from exposure to
chrysotile is considerably higher (28.8/1000) than the NOHSC estimate and was
based on a coefficient of 0.01 obtained from epidemiological studies on textile
workers. More recently, US NIOSH studies put this coefficient at closer to 0.02
(Stayner et al. 1997) ?see Table 21. According to Lash (1997), a meta-analysis
of all chrysotile cohorts (with dose-response data), suggests a lower coefficient of
0.0025.
None of the above estimates include mesothelioma (due to the lack of adequate
dose-response data) and therefore may understate the overall incremental cancer
risk.
7.6.2 Uncertainties in chrysotile risk estimates
The risk estimates used in the calculations in Table 21 were derived from past
exposures to relatively high levels of chrysotile. Current levels of exposure are
much lower than the levels estimated in the cohort studies (presented in Table 20)
and as such risk extrapolations in Table 21 may be an overestimate.
There are several other reasons why there is a great deal of uncertainty regarding
these risk estimates, which include:
1. Past occupational exposures have generally involved exposure to a mixture of
asbestos fibres. As it appears likely that different types of asbestos have different
degrees of hazard, it is difficult to determine the risk attributable to chrysotile per
10
Known also as the risk coefficient
70 Priority Existing Chemical Number 9
se. In addition, commercial chrysotile often has low levels of tremolite
contamination.
2. Fibre size, such as difference in fibre size between different chrysotile industries,
probably influences the degree of hazard and/or potency.
3. There is a long latency between exposure to asbestos and development of lung
cancer. Hence, it is not possible to state definitively what fibre type and level of
exposure caused the disease. Consequently, risk estimates are related more to
duration of employment rather than intensity of exposure.
4. A linear, non-threshold model may not be an appropriate model as there is some
evidence suggesting that lung cancer due to chrysotile exposure may have a
threshold for effect.
5. Past exposure estimates (both quantitative and qualitative) are subject to
considerable error. For example, conversion of historical results in mpcf units to
fibres/mL has inherent uncertainties.
6. There is a high background level of lung cancer in the general population due to
smoking. Cases of lung cancer attributable to asbestos cannot be distinguished
from those due to smoking. Attribution can only be assessed in terms of excess
of lung cancers above a control population, hence the choice of control
population is critical.
7. The identification of the disease is dependent on medical diagnosis, however
autopsies are not always conducted.
The impact of some of these uncertainties can be accounted for to some extent.
For example, it is considered that (1) and (2) are largely accounted for by basing
risk estimates on epidemiological studies where exposure was only to chrysotile
in the most relevant industry.
For the remainder of the above uncertainties it is unclear what influence they
have on the risk estimates and how they should be accounted for. For example,
recently there has been some debate in the literature as to whether a threshold or
non-threshold model should be used when predicting risk due to chrysotile
exposure. Meldrum (1996) states that based on balance of toxicological
evidence, the linear no-threshold model for chrysotile-induced lung cancer may
not be appropriate. An association between pulmonary fibrosis and lung cancer is
evident in that both diseases show a similar dose-response relationship with
respect to asbestos exposure, similar latent periods for development, similar
dependence on fibre type and size, and both diseases originate from the same
underlying chronic inflammatory condition. This suggests that asbestos-induced
lung cancer, like fibrosis, is a threshold phenomenon. Epidemiological data alone
are not able to clearly distinguish between the possibility of a threshold or a non-
threshold model due to the relatively high background rate of lung cancer in the
human population. There is at present no consensus with respect to a threshold
level of exposure for chrysotile below which there is no risk of disease.
71
Chrysotile Asbestos
7.7 Conclusions
Chrysotile, like all other asbestos forms, causes asbestosis, lung cancer and
mesothelioma in humans and animals and has been shown to cause these diseases
with a dose-response relationship. Chrysotile is classified as a known human
carcinogen (IARC, 1987; NOHSC, 1994c). It has been shown that smoking and
asbestos act in a synergistic manner, increasing the overall risk of lung cancer.
There is continuing debate over the potency of chrysotile, particularly in relation
to the amphiboles; crocidolite and amosite. There is accumulating evidence to
indicate that chrysotile is less potent in causing asbestosis, lung cancer and
mesothelioma, although this issue has not been conclusively resolved.
Risk estimates are based on the incidence of lung cancer, as this is the overriding
risk from asbestos exposure and insufficient dose-response data exist to estimate
risks of mesothelioma. Risk estimates have assumed a linear, non-threshold
approach and are extrapolated from high to low doses. Although risk estimates
for chrysotile exhibit a dose-response relationship, the degree of risk appears to
be dependent on the type of industry. The most relevant industry in Australia is
the friction product manufacturing industry. NOHSC have estimated the risk of
lung cancer in Australia based on the estimated risk in overseas friction product
industries (NOHSC, 1995a). Analysis of other cohorts by US agencies provide
higher risk estimates (up to 30 fold).
There are many problems associated with low-dose risk extrapolation, such as the
assumption of a linear relationship. However as insufficient data exists to
indicate a threshold exposure for effect, the linear extrapolation methodology
provides a conservative worst-case scenario estimate of risk. Other confounding
factors in estimating risks from epidemiological data are possible contamination
by other fibre types and inaccurate estimates of historical exposures.
Although the hazards of chrysotile (asbestosis, lung cancer and mesothelioma)
have been researched and discussed in great detail, there are still many
uncertainties regarding the level of risk associated with its use. Therefore, any
estimate of risk should be used with caution.
72 Priority Existing Chemical Number 9
8. Public Health Assessment
There is the potential for public exposure during the transport, storage and
disposal of raw chrysotile, emissions from manufacture and from end-use of
products containing chrysotile, particularly friction products.
8.1 Public exposure
8.1.1 Manufacture
In Australia, raw chrysotile is currently fabricated in friction materials and gasket
sheeting in 3 locations and into epoxy resin adhesive at another site.
Detailed information on the manufacturing processes and dust emission control
measures can be found in Section 6 (Occupational Exposure) and Section 10
(Risk Management), respectively.
In general, manufacturing processes are carried out in enclosed systems and dust
levels are controlled by dust extraction with automatic plant shutdown when dust
levels exceed prescribed limits. Monitoring of manufacturing and processing
activities has revealed personal exposure levels generally < 0.1 f/mL with most
samples 0.05 f/mL. Significant exposure of the public to chrysotile fibres from
these manufacturing processes is therefore unlikely.
8.1.2 End-use
Automotive applications are likely to be the major source of public exposure to
chrysotile dusts. Chrysotile friction materials contain between 40 and 60%
chrysotile. A proportion of the end-use products containing chrysotile may be
sold directly to the public, particularly automotive friction products and gaskets.
In the home mechanic situation, little if any personal protective equipment is
likely to be worn when replacing brake pads and shoes, clutch plates or engine
gaskets. In the case of gaskets, generation of significant quantities of dust is
unlikely as the chrysotile is bound into the matrix of the gasket. Similarly dusts
created from clutch facings tend to be enclosed in the transmission of the vehicle
and most replacement clutch facings do not contain chrysotile. During the
changing of brake pads and drum shoes, however, significant exposure is
possible. In commercial operations compressed air is generally no longer used to
remove excess dust and improved housekeeping practices has reduced exposure
levels occupationally and as a consequence, has reduced the likelihood of public
exposure from this source. The home mechanic however, may have significant
intermittent exposure during the changing of brake pads and shoes.
Generation of chrysotile dusts at busy traffic intersections, by braking vehicles, is
a known source of public exposure. Studies (Jaffrey, 1990) on the levels of
chrysotile fibres at two busy (approximately 2000 vehicles/hr) London
intersections found total asbestos levels of between 5.5 x 10-4 to 6.2 x 10-3 f/mL.
Of the fibres detected, less than 10% had dimensions within the peak hazard
range (>5 祄 long by < 3 祄 wide) prescribed by WHO (Spurney 1995).
73
Chrysotile Asbestos
Another study carried out in Australia found airborne asbestos levels to be very
low (0.5 particles/mL) in the immediate vicinity of the intersection braking area
of the Tullamarine (SE exit) freeway (Alste et al 1976). The particles consisted
of small bundles of fibres and the number of fibres in the bundle was not
determined. The majority of fibres had a maximum dimension of 2 祄 and the
crystal structure of the fibres was unchanged. At a different location (30 metres
from the nearest traffic), levels were below the limits of detection (Alste et al.
1976). Therefore, exposure from this source is likely to be highly localised and
intermittent for most people.
The use of chrysotile in industrial gaskets, such as in petrochemical plants, is
unlikely to yield significant public exposures. Similarly, the use of `sag resistant'
epoxy resins (containing approximately 2% chrysotile) in building and
construction work, is unlikely to lead to significant public exposure as the
chrysotile is bound into the adhesive matrix. These applications are generally
limited to large industrial complexes or commercial buildings, utilise relatively
small volumes of chrysotile at any one location, are likely to enclose the material
between metal or masonry surfaces, and would not generally be expected to
produce significant quantities of free chrysotile fibres.
8.1.3 Transport and storage
Imported raw chrysotile is landed in 50 kg polyethylene woven bags within a
sealed sea going container which is shipped, intact, to manufacturing sites. The
nature and construction of these containers is such that, other than in
extraordinary circumstances, a transport accident is unlikely to release significant
quantities of raw chrysotile. The shipment of bulk raw chrysotile in non-
contained cardboard boxes could pose a significant public hazard in the event of a
transport accident, however this would be localised and could be ameliorated by
vacuum removal of dispersed material. Finished products containing chrysotile
bind the fibres into the matrix of the product. Shipment of the types of products
currently manufactured in Australia is unlikely to result in significant public
exposure to chrysotile fibres.
8.1.4 Disposal
Waste chrysotile, the polyethylene bags in which it is supplied, and chrysotile
containing materials from the manufacturing process, are disposed to landfill by
licensed disposal contractors. As chrysotile fibres are unlikely to be mobile in the
soil or water table, landfill is not inappropriate from a public health perspective.
8.2 Public health risks
The health effects of chrysotile are described in detail in Section 7.
Chrysotile is unequivocally a human carcinogen, however the risk to the public
associated with its continued use is dependent on the nature of the material to
which the public is exposed and the level, frequency and duration of exposure.
The most prevalent chrysotile induced disease is lung cancer, hence an
assessment of the likely risk to the public of this hazard, from current sources of
public exposure, will provide a qualitative indication of the likely risks for
mesothelioma. At the levels of exposure likely to be encountered by the public
74 Priority Existing Chemical Number 9
the risk of asbestosis, which follows a dose response relationship, is essentially
zero (IPCS, 1986).
As the major source of public exposure to chrysotile is that generated from brake
linings in commercial and private vehicles, exposure is likely to be widespread
with exposure via oral, dermal and inhalation routes, predominantly by inhalation
and dermal contact.
Levels of exposure will vary widely, with rural residents expected to have the
lowest exposure levels and those living or working adjacent to busy intersections
having the highest exposures. As the levels of exposure at peak generation points
such as traffic intersections remains low in absolute terms, and the levels tail off
rapidly as measurements are taken further from the point of generation,
cumulative exposures for the bulk of the population are expected to be low.
In assessing the risk to the public from exposures likely to be encountered in the
worst case scenario, by a newspaper seller on the corner of a major traffic
intersection for example, the most relevant epidemiological data available comes
from studies on workers in friction material manufacturing plants. NOHSC have
estimated that the number of lung cancers per 1000 workers lifetimes (assuming
mixed smoking habits and 40 years of continual exposure) expected in the
Australian friction industry to be 1 to 2 cases from exposure to 1 f/mL, 1 case at
0.5 f/mL and 0.2 case at 0.1 f/mL (NOHSC, 1995a). Because of the process of
derivation of this figure, particularly the no threshold assumption with low dose
linearity and the level of exposure, it is considered a conservative estimate of the
risk.
As the nature of the dusts generated from milling, cutting and grinding of
chrysotile-based friction materials in manufacturing plants is likely to be either
similar to, or considerably more hazardous than, that produced by automotive
traffic, the conclusion that the risk to the public from exposure to dusts generated
by commercial and private vehicles is likely to be low, is reasonable. There is
also some evidence to suggest that the fibres generated by vehicles may be less
hazardous. Chrysotile fibres in the debris from brake shoes and clutch linings
measured in automotive workshops tend to be relatively short with a large
proportion < 1 祄 and 84% < 0.4 祄 in length (Plato et al., 1995). These
figures are consistent with those obtained at busy traffic intersections discussed
above. As these fibres are smaller than the peak hazard dimensions (see Section
8.1.2), the risk from exposure to them will be lower than to exposure to the raw
chrysotile prior to fabrication.
In the home mechanic setting, a risk of substantial intermittent exposure to
chrysotile dusts exists. The degree of exposure and the risks associated with this
are largely unquantifiable, nevertheless a warning to avoid inhalation of brake
housing dusts during exchange of brake pads/shoes should be carried on or
included in their packaging. In a study of automotive mechanics in Sweden
(Plato et al., 1995), time weighted exposures in the 1960s were given as 0.11-0.41
f/mL falling to 0.003-0.08 f/mL in 1985. The `Automotive Aftermarket Survey',
conducted during this assessment, found exposure levels were less than 0.03 f/mL
during the replacement of friction products in vehicles. Earlier studies where
dusts were blown out of the brake housing with compressed air exposures of up
to 40 f/mL were recorded. Although the home mechanic is less likely to employ
the precautions likely to be used at automotive repair centres, their less frequent
75
Chrysotile Asbestos
exposure to friction material dusts is likely to yield lower time weighted
exposures. Based on the NOHSC risk estimates, the maximal exposures reported
for mechanics, if applied to home mechanics, would yield approximately one
additional lung cancer case per 1000 lifetimes in home mechanics. As discussed
above, this is likely to be an overestimate of the risk.
The majority of new cars manufactured and imported into Australia no longer
include asbestos containing components. As a consequence, the generation of
chrysotile-containing dusts from this source will gradually decline as the
proportion of chrysotile-free vehicles increases. The general decline in use of
chrysotile containing parts is assisted by the trend away from drum brakes
towards disc brakes. A high proportion of vehicles may be fitted with chrysotile-
containing brake pads or shoes in the automotive aftermarket and in home car
maintenance, due to the lower cost of chrysotile components. However, the
overall use of chrysotile-containing brake parts is unlikely to rise because of the
increased use of non-asbestos brakes in most new vehicles.
In general, as exposures experienced by the public will normally be considerably
lower and less frequent than those experienced in the industrial environment, the
expected lung cancer incidence in the public due to exposure to chrysotile will be
lower than those estimated for workers. Based on the NOHSC risk estimates for
the industrial setting, the risk to the public, even in the worst case situation, is
considered to be low. Should a threshold model for chrysotile induced lung
cancer prove to be more accurate, then the current NOHSC risk estimates will
tend to overstate the actual risk and the risk to the public will be even lower.
The International Programme on Chemical Safety (IPCS) in assessing the risk to
the public from asbestos exposure concluded that "the risks of mesothelioma and
lung cancer cannot be quantified reliably and are probably undetectably low" and
that "the risk of asbestosis is virtually zero" (IPCS, 1986). The conclusions of the
IPCS, although referring to a broader range of mineral fibres than chrysotile
alone, are consistent with the conclusions drawn from the discussion above.
8.3 Conclusions
Chrysotile is a known human carcinogen, however the risks associated with its
use are dependent on the nature of the application and of the product utilised.
Based on the data available, the continued use of chrysotile on friction surfaces,
gaskets, and in seals for critical industrial applications is not expected to present a
significant hazard to public health. As such there are no objections to the
continued use of chrysotile in these applications, however, continued progress
towards a phase out of this material in favour of less hazardous materials is
supported, where this phase out does not introduce greater risks through the lesser
performance of substitute materials.
76 Priority Existing Chemical Number 9
9. Environmental Assessment
9.1 Environmental fate and exposure
9.1.1. Release from manufacture
In Australia, raw chrysotile emissions/release may arise from the manufacture of
friction products, CAF sheets for production of gaskets and the manufacture of
`non-sag' epoxy resin. Detailed information on manufacturing processes can be
found in Section 6 (Occupational Exposure).
At the Bendix Mintex site mixing, moulding and finishing processes during
manufacture of friction products are carried out under dust extraction. The bag
filters used to filter extracted air from the plant are a potential release point. Dust
waste disposal quantities for 1994 from Bendix Mintex Pty Ltd, i.e. the amount of
chrysotile wastes collected in the fabric filter dust collector, was estimated at
1085 kg per day. Imports of chrysotile imported in this year were 947 tonnes.
Assuming 260 days per annum where production occurs, losses collected through
the fabric filter dust collector account for almost 30% of the imported chrysotile.
Solid friction material scrap containing chrysotile landfilled as part of the
companies solid scrap was estimated at 320 kg per day. Car brakes and clutches
contain between 40 and 60% asbestos (Bendix Mintex) and assuming the
maximum ratio, up to 190 kg per day will be released with solid friction material
scrap. This accounts for a further 5% of the imported chrysotile.
Another use of raw chrysotile in Australia is the manufacture of CAF sheeting for
gasket production (carried out by Richard Klinger Pty Ltd). Manufacturing of the
raw material is carried out in Perth, while gasket processing (e.g. cutting) is
performed at both Perth and Melbourne factories. Richard Klinger estimates that
a maximum of 600 tonnes of CAF (510 tonnes of chrysotile) is produced in any
one year. The volume of waste generated and sent to landfill is estimated at 35
tonnes per year, with an additional 30 tonnes recycled within the processing
plant. Further, the plant's dust extraction system collects approximately 25 kg of
general dust per week, of which a fraction is asbestos fibre, all of which is then
recycled through the system.
Waste disposal
It is known that Bendix Mintex disposes of its waste to specifically engineered
landfills. Richard Klinger bags their waste in polyethylene containing an
asbestos warning. These are sealed and placed in an asbestos waste collection bin
for disposal by a licensed waste contractor. This process is in accordance with
the disposal methods recommended by the Asbestos Institute for friable waste
(The Asbestos Institute & Quebec Asbestos Mining Association, 1993). With
regard to disposal of empty bags in which chrysotile is imported, Bendix Mintex
seal (in plastic bags) these bags immediately they are emptied into the mixer. As
with chrysotile waste, these bags are disposed of to a controlled disposal site.
77
Chrysotile Asbestos
9.1.2 Release from end-uses
Major uses (of both processed raw chrysotile and imported products containing
chrysotile) is for friction material and gaskets. The major release expected from
these uses will be when used parts are sent to landfill. This will result in diffuse
release around the country.
Release of chrysotile from brake linings during use appears limited. A study
conducted in the Greater London Area over two busy intersections stated that the
levels of asbestos fibres generated by the high traffic density was low. The
combined results of all samples collected at these sites show the levels of all sized
fibres to range from 5.5x10-4 to 6.2x10-3 f/mL (Jaffrey, 1990). It is difficult to
find ambient air concentrations for asbestos in the Australian environment.
However, Environment Australia believes that, unless asbestos is used or occurs
naturally in the area, the background concentrations will be negligible. The levels
measured by Jaffrey, (1990) are certainly lower than the current NOHSC
occupational exposure standard (TWA) concentration for chrysotile of 1 f/mL11.
It is claimed that the amount of asbestos found in the dust arising from braking is
rarely more than 1%12 of the wear product (Asbestos Information Committee,
1975). It is not known what quantity of chrysotile is imported in brake linings
and other friction materials, but ABS data indicates in excess of 750,000 articles
(brake linings, pads and clutch facings) being imported in 1997 containing
asbestos and therefore possibly containing chrysotile. Assuming each unit
weighs 200 g and contains 50% chrysotile, this equates to around 150 tonnes of
chrysotile per annum. Assuming a further 1000 tonnes of chrysotile present in
friction products manufactured in Australia, it is estimated that (assuming a worst
case scenario of 1% release per annum, i.e., all products are completely worn in
one year13) around 11.5 tonnes of chrysotile will be released per annum
countrywide or 32 kg per day spread all around the country. It is acknowledged
that this figure may be an overestimate, as studies have shown that some of the
chrysotile is degraded to magnesium silicates and forsterite (section 9.1.3). In
addition, some of the debris will be retained in the brake system and removed and
disposed of under controlled conditions.
The remainder of the chrysotile, as used friction or gasket products is likely to be
disposed of to landfill.
9.1.3 Fate
Terrestrial fate
The majority of waste chrysotile from manufacturing (i.e. from dust extracted and
caught in fabric filters, or as off cuts from end products) is expected to be
disposed of to landfill. This waste will be secured in landfill through containment
11
Where exposure to other asbestos fibres is possible, the NOHSC exposure standard is 0.1 f/mL
(NOHSC 1995d).
12
This figure was questioned (as being an underestimate) during the variation phase of this report.
However, it was concluded from further assessment of the literature that this figure is
representative of the best quality data available.
13
This does not imply that every vehicle will have brake linings replaced on an annual basis, but
reflects the annual import/manufacture quantities and hence the amount of chrysotile used per
annum.
78 Priority Existing Chemical Number 9
in plastic bags. It is known that at least one of the manufacturers sends such
waste to a specifically engineered landfill.
Waste from use (i.e. used linings and gaskets) will be disposed of to unsecured
landfill, and would not be readily available for transport by wind or water as it
would be encapsulated in end articles, and possibly bagged. Due to temperature
decomposition during use it is possible that these worn articles will contain more
forsterite14 than chrysotile with overall chrysotile levels reduced even more.
Normal use of motorised vehicles is associated with wear of the brake and clutch
linings, which will liberate a small amount of chrysotile to the terrestrial
environment. Of the material dislodged in this manner, it is stated that in cars,
81.6% of the wear material was deposited on the ground (where it will be
available for transport by wind and water), 14.4% retained in the brake housing
and 3% emitted to the atmosphere (Jaffrey, 1990). During end use as friction
materials or in gaskets, the chrysotile will be exposed to high temperatures. It
appears that at temperatures of 500-6000C chrysotile decomposes rapidly by loss
of water to form non-fibrous magnesium silicates and forsterite although there is
some question as to whether although there is some question as to whether
braking during town driving generates enough heat to effect this change.
Aquatic fate
It can reasonably be expected that chrysotile fibres from end use will reach
aquatic systems arising from dust generated during brake wear and to a lesser
extent, from disposal to unsecured landfill. Where present as a result of the
above activities, fibres could be transported to nearby water bodies through wind
or runoff to stormwater drains as a result of their small size.
Degradation
Chrysotile is not expected to degrade in aquatic systems although some
degradation may occur under acidic conditions. One literature reference claims
asbestos fibres are highly persistent in water, with a half-life greater than 200
days (University of Virginia, 1996), although methods of testing are not known.
Soil/groundwater
Asbestos fibres have very small dimensions, hence they can be quite mobile.
Water turbulence may suspend and transport fibres over long distances in surface
waters. Leaching potential for asbestos in soils is not well understood, especially
with regard to concerns over drinking water quality (Pennsylvania State
University, 1994).
9.2 Environmental effects
There is a paucity of data available as to the effects of asbestos in the
environment.
Environmental effects are more likely to be of a physical rather than chemical
nature as a result of the fibrous nature of asbestos. Data are insufficient to
14
Forsterite is a member of the olivine series of iron magnesium silicates, and is non-fibrous. It is
magnesium rich with a formula approximating Mg2SiO4 (Amethyst Galleries Inc, 1996).
79
Chrysotile Asbestos
determine if asbestos poses any acute or chronic toxicity hazard to plants birds or
land animals. It is possible that birds or land animals may develop cancers or
other long-term effects from inhalation of asbestos fibres (Asbestos Information
Committee, 1975), although it is improbable animals will suffer chronic exposure
as they are unlikely to remain for long periods of time in areas where high
concentrations of fibres are expected (e.g., road intersections).
A study of the effects of chrysotile was carried out by Belanger and co-workers
on all life stages of the cyprinodontid fish, the Japanese medaka (Oryzial latipes),
including egg hatchability and survival, larval to juvenile growth and survival,
histopathology and asbestos bioaccumulation and adult reproduction. Studies
demonstrated that larval and juvenile fish were the most sensitive with significant
growth reductions occurring at 106 to 108 f/L. At 1010f/L, 100% mortality was
recorded in 56 days of exposure (Belanger et al., 1990).
Direct evidence of chrysotile accumulation was present with concomitant
epidermal lesions. A small percentage (5%) of fish at 1010 f/L developed ventral
non-invasive epidermal hyperplastic plaques (Belanger et al., 1990.
Reproduction tests resulted in 33% spawning frequency from 104 and 105 f/L
compared to control populations and 25% more viable eggs (Belanger et al.,
1990).
The study concluded that chrysotile may represent a significant environmental
hazard, especially to juvenile fish and that asbestos should receive greater
attention than it has historically. Environment Australia considers the hazard will
be low as it is unlikely that fibre concentrations in water will approach those
tested above. Ambient levels of asbestos in water are not known, however,
assuming ambience in water similar to that for air, a concentration of chrysotile
of 10-9 f/L would be a good approximation.
9.3 Environmental risk assessment
Anthropogenic releases outlined above, if managed in the manners described, are
unlikely to be of concern to terrestrial species from inhalation due to the disperse
nature of fibres entering the atmosphere.
Bearing in mind the outcomes of the fish toxicity study cited above, it is possible
to derive a predicted environmental concentration (PEC) to determine the
likelihood of a hazard existing.
Extrapolation of the upper concentration of 0.0062 f/mL (results from the study
by (Jaffrey, 1990) on asbestos fibres release from vehicular traffic in London) by
assuming a direct correlation from the top 1 mL above ground, provides an area
measurement of 0.0062 f/mm2. Assuming roadways cover 10% of a hectare, this
equates to 2.6 x 106 fibres per hectare (every 4 hours). Assuming this is a
constant rate and there is no loss of fibres through wind movement, then after a
week, 2.6 x 108 fibres will be present per hectare. If rain washes these fibres into
a standing body of water, 1 hectare in area and the rain fills the body of water to
15 cm depth, this quantity of fibres will result in a concentration of around 174
f/L. This is four orders of magnitude lower than the 106 f/L shown to cause
growth reduction in Japanese medaka fish, and suggests a low environmental
hazard.
80 Priority Existing Chemical Number 9
Risk is further mitigated when accounting for dispersal of fibres through wind,
and further dilution in flowing water and coastal areas.
9.4 Conclusions
Based on available data for Australia, it can be predicted that the use of chrysotile
(including manufacturing) when used in the manners outlined in this report, will
result in a low hazard to the environment.
When chrysotile is encapsulated in end use products such as brake linings and
epoxyresin adhesives, it is unlikely fibres will be in a form where an
environmental hazard is posed. Therefore, disposal of used parts to standard
municipal landfills is acceptable.
81
Chrysotile Asbestos
10. Risk Management
In this section, measures currently employed in the management of human health
risks from potential exposure to chrysotile and other asbestos fibres are discussed.
All uses are covered, as background for consideration of approaches which may
be appropriate for those uses of chrysotile which fall within the scope of this
assessment.
The information reviewed includes national and international standards, together
with relevant guidance material, MSDS and labels. Where appropriate, measures
for managing risks from exposure to asbestos are dealt with separately for
specific workplace scenarios.
In addition to the provision of relevant information by manufacturers (applicants)
and users of chrysotile products, data were also obtained from site visits, surveys
and questionnaires and a commissioned consultancy project to survey current
national and international regulatory controls for chrysotile and other asbestos
products.
In Australia and overseas, legislation is currently in place that restricts or controls
activities which involve exposure to asbestos.
General legislative measures currently taken for the control of asbestos include:
? restricting use through prohibition (often subject to exemptions) of imports
and sale, manufacturing or use and/or by licensing certain activities such as
import and waste disposal;
? regulating its use in the workplace through specific restrictions on the method
or standard of carrying out an activity, such as prohibitions against exceeding
prescribed exposure standards;
? labelling requirements for asbestos and asbestos-containing products; and
? controls on methods for packing and transportation.
Controls are generally imposed by legislation or regulations (or their equivalent)
on specific activities, and enforced under occupational health and safety or
environmental legislation, or both.
Legislation commonly includes `chrysotile' in the definition of asbestos, and as
such chrysotile is usually regulated under regulations pertaining to asbestos. The
focus of most legislation is on asbestos manufacturing activities and exposure to
asbestos in construction and demolition work. Regulation tends to be "risk
based", focussing on high risk activities (such as spraying of asbestos containing
substances) and prevention of risk to employees. With the exception of
construction activities, regulation is not generally directed at industry specific
risks.
82 Priority Existing Chemical Number 9
10.1 Regulation of asbestos in Australia
During the preparation of this report, chrysotile was regulated as a Priority
Existing Chemical (PEC) under the Commonwealth Industrial Chemicals
(Notification and Assessment) Act 1989.
Chrysotile is regulated in Australia through various State and Territory legislation
relating to occupational health and safety, dangerous goods and to a limited
extent through environmental protection. In some cases a national framework or
model is in place to enable uniformity.
10.1.1 Workplace regulation
NOHSC has declared several national standards under s.38(1) of the National
Occupational Health and Safety Commission Act 1985 (Cwlth) which address
risks associated with asbestos and prescribe actions to be taken to address such
risks. National standards, which may take the form of national model regulations,
are instruments of advisory nature only, except where a law other than the
NOHSC Act , or an instrument under such a law, makes them mandatory. The
expectation is that national standards will be suitable for adoption by
Commonwealth, State and Territory governments. Table 22 provides information
on NOHSC Standards and Codes relevant to the regulation of asbestos in the
workplace, together with the current status of adoption in State/Territory OHS
regulations.
Also of relevance to the regulation of asbestos/chrysotile are the following
documents15, called up under the Hazardous Substances Standard and Code:
? List of Designated Hazardous Substances (NOHSC, 1994c)*
? National Code of Practice for the Labelling of Workplace Hazardous
Substances (NOHSC, 1994d)
? National Code of Practice for the Preparation of Material Safety Data Sheets
(NOHSC, 1994e)]
? Guidelines for Health Surveillance (Asbestos) (NOHSC, 1995c)*
? Guide to the Control of Asbestos Hazards in Buildings and Structures
(NOHSC, 1988)*
? Australian Code for the Transport of Dangerous Goods by Road and Rail
(FORS,1998)*
The key elements in the management of occupational risks from chrysotile are:
? workplace control measures;
? hazard communication and training; and
? workplace monitoring (air monitoring and health surveillance).
15
Documents marked with an asterisk (*) contain requirements specific to chrysotile.
83
Chrysotile Asbestos
Table 22 ?Status of implementation in Australian jurisdictions of
NOHSC Standards and Codes relevant to asbestos/chrysotile
Standard/Code
CWLTH
NSW
QLD
ACT
TAS
VIC
WA
NT
SA
Hazardous A A A A A A A A A
Substances
- Standard and
Code1
Asbestos (1988) A A A A A A A A A
- Code and
Guidance Note2
A A C Y A A A A A
Carcinogens (1994)
- Standard and
3
Code
Exposure A A A A A A A A -
Standards (1990)
- Standard4
A = Adopted or committed to adopt
C = Under consideration
Y = Yet to be considered (standard recently declared or standard to be first reviewed by
state advisory body)
1
Refers to National Model Regulations for the Control of Workplace Hazardous
Substances and National Code of Practice for the Control of Workplace Hazardous
Substances (NOHSC, 1994b).
2
Refers to Code of Practice for the Safe Removal of Asbestos and Guidance Note on the
Membrane Filter Method for Estimating Airborne Asbestos Dust (NOHSC, 1988).
3
Refers to National Model Regulations for the Control of Scheduled Carcinogenic
Substances and National Code of Practice for the Control of Scheduled Carcinogenic
Substances (NOHSC, 1995b).
4
Refers to Exposure Standards for Atmospheric Contaminants in the Occupational
Environment (NOHSC, 1995d).
OHS control measures
According to the NOHSC National Model Regulations for the Control of
Workplace Hazardous Substances (NOHSC, 1994b), exposure to hazardous
substances should be prevented or, where that is not practicable, adequately
controlled so as to minimise risks to health. The NOHSC National Code of
Practice for the Control of Workplace Hazardous Substances (NOHSC, 1994b)
provides further guidance in the form of a hierarchy of control strategies, namely:
? elimination;
? substitution;
? isolation;
? engineering controls;
? safe work practices; and
? personal protective equipment.
The following sections provide a summary of information on control measures
relevant to the manufacture of chrysotile products and their end-use. Information
on the manufacture of chrysotile products was provided by applicants.
Information on end-use was obtained from a survey of automotive garages and
84 Priority Existing Chemical Number 9
gasket workshops, previously described as the `Automotive Aftermarket Survey'
(see Appendix 2). Control measures for the maintenance or removal of asbestos
from past uses, such as asbestos sheeting, are not covered in this report and
further information can be obtained from the Guide to the Control of Asbestos
Hazards in Buildings and Structures and Code of Practice for the Safe Removal
of Asbestos (NOHSC, 1988).
Elimination and substitution
Where an activity involves the use of a hazardous substance that is not essential
for that use, the hazardous substance should be eliminated wherever practicable.
Elimination is defined as the complete removal of a chemical from a process or
product. Brake pads and gaskets of some material are an essential requirement
and therefore total elimination of such is not possible. Where elimination is not
practicable, substitution of the chemical should be considered. Substitution
includes substituting with a less hazardous substance (alternative), the same
substance in a less hazardous form or process.
An asbestos alternative is any material that replaces asbestos in a commercial
product. The development of chrysotile substitutes has been vigorously pursued
for many years due to the health risks posed by the release of asbestos fibres
during manufacture, use, repair and disposal of asbestos-containing products.
Currently there is no one substitute material available for all uses that exhibits all
the advantageous properties of chrysotile. Since no single alternative material is
available, manufacturers use blends of different types of material to produce the
final product. The use, availability and health effects of asbestos alternatives are
discussed in detail in Section 11.
Isolation
Isolation involves separation of the process from people by distance or the use of
barriers to prevent exposure. For Bendix Mintex and Richard Klinger, handling
of raw chrysotile takes place in a separate area and away from workers involved
in other manufacturing operations.
Engineering controls
Engineering controls are plant construction or processes which minimise
exposure to hazardous substances such as ventilation, enclosure (closed process)
and automation.
The three manufacturers of chrysotile products in Australia have various
engineering controls in place at their manufacturing sites. These controls include:
? dust extraction systems which operate during different stages of the
manufacturing process;
? automated process for the opening and removal of the woven polyethylene
bag which contains the raw chrysotile and disposal of the bag;
? mixing vessels enclosed and operated under negative pressure;
? automated decanting of asbestos mixes and machining of final product
? localised automated dust extraction; and
85
Chrysotile Asbestos
? centrally ducted vacuum systems.
Detailed information on the manufacturing processes can be found in Section 6 -
Occupational Exposure.
Engineering controls in place at five service garages, three brake bonding
workshops and one gasket workshop, surveyed as part of an investigation of the
automotive aftermarket, included the following:
Service garages:
? natural ventilation (considered adequate in 4 of the 5 workshops)
Brake bonders:
? local exhaust ventilation
Gasket workshop:
? use of machines to cut gaskets
Safe work practices
Safe work practices are administrative practices that require people to work in
safer ways. For the companies manufacturing chrysotile products the following
safe practices are in place:
? all work areas are vacuumed before leaving work area and vacuuming any
spills or loose chrysotile fibres;
? exposed areas of skin are washed before eating and drinking;
? clothes are cleaned by vacuuming before leaving work areas;
? portable high efficiency vacuum cleaners in place for housekeeping;
? processes that create dust are not permitted;
? processes (such as die cutting and winding) which do not create dust when
cutting CAF sheets are used;
? preventive maintenance program in place for plant, equipment and extraction
systems;
? damaged bags of chrysotile are sealed immediately and surrounding area
vacuumed;
? damaged chrysotile bags are consumed immediately in the manufacturing
process;
? all waste chrysotile or materials containing chrysotile are collected into
polyethylene bags. Bags are printed with an asbestos warning and sealed
with a bag tie and placed in an asbestos waste collection bin for collection;
and
? disposal of waste drums by licensed disposal contractor.
Safe work practices adopted by end-users of chrysotile products included:
Service garages
? wet rag used to transfer dust into plastic bag;
86 Priority Existing Chemical Number 9
? wet brushing and an aerosol spray for dusty jobs;
? aerosol water spray for back drum brakes (disc brakes not dusty);
? watering of brakes if dusty;
? aerosol can (containing 48% dichloromethane and 12% isopropanol) used for
dust control and as a degreasing agent;
? no cutting and grinding of brake linings for brake drums and brake disc pads
(these are sent to brake bonders for bonding); and
? vacuum for cleaning workshop area.
Brake bonders
? wet brushing
Gasket workshops
? No special precautions were taken at a gasket workshop visited as very little
dust released.
Personal protective equipment
In general, the use of personal protective equipment (PPE) as a control measure
should be limited to situations where other control measures are not practicable or
where it is used in conjunction with other measures to increase protection.
PPE used by chrysotile product manufacturers in Australia include:
? respiratory protection (e.g. half-face mask respirators with class M cartridges
or 3M 8710 respirators);
? safety glasses or goggles in designated eye protection areas or on designated
machines (e.g. grinders);
? cotton overalls; and
? gloves for handling of materials.
In most service garages and gasket and brake bonding workshops, overalls were
worn by all employees. All brake bonding shops and one service garage reported
that respiratory protection was used during times of potential exposure to
asbestos. During site visits it was observed that a 3M 8710 mask was used during
cutting and grinding of brake linings (in brake bonding) and during the changing
of brake linings (service garage).
NSW WorkCover has published a guidance document on the use of personal
protective equipment (NSW WorkCover, 1996). Personal protective equipment
should be selected according to manufacturers/suppliers recommendations,
usually available in the MSDS. Personal protective equipment should also meet
the appropriate Australian Standards (see information contained in sample MSDS
at Appendix 6).
87
Chrysotile Asbestos
Hazard communication and training
Material Safety Data Sheets (MSDS)
MSDS are the primary source of information needed to handle chemicals safety.
In accordance with the NOHSC National Model Regulations for the Control of
Workplace Hazardous Substances (NOHSC 1994b) and corresponding State and
Territory legislation, suppliers are obliged to provide MSDS to their customers
for all hazardous substances.
An MSDS (prepared by the Asbestos Institute) submitted by Richard Klinger,
was the only MSDS for raw chrysotile available for assessment. Assessment
against the NOHSC National Code of Practice for the Preparation of MSDS
(NOHSC 1994e) indicated it did not contain the following information:
? statement of hazardous nature;
? Australian occupational exposure standard for chrysotile; and
? contact details of the company.
Further, the health effects information is both inadequate and inaccurate.
Terminology, such as `overexposure' is not defined (essential, given the
carcinogenic nature of chrysotile). Information on preventive measures was also
considered inadequate and referred to ILO or US regulations rather than the
respective Australian regulations. In addition, the MSDS did not specify the type
of personal protective equipment to be worn and in particular there is no mention
of respirator use.
For chrysotile products, a number of MSDS were obtained from the NICNAS
survey, from Bendix Mintex (friction products) and Richard Klinger (CAF
sheeting/gasket products). In general these MSDS provided adequate
information, particularly in the following areas: ingredient listing and quantities,
health hazard, Australian exposure standard, PPE, safe handling statements and
contact details for further information.
A sample MSDS for chrysotile, prepared in accordance with the MSDS Code, is
provided in this report in Appendix 6. This sample MSDS is for guidance
purposes only. Under the National Model Regulations, manufacturers and
importers have the responsibility to prepare their own MSDS and ensure that the
information is up-to-date and accurate.
Labelling
Under the NOHSC National Model Regulations and Code of Practice for the
Control of Workplace Hazardous Substances (Model Regulations) (NOHSC,
1994b) and the corresponding State and Territory legislation, suppliers of
hazardous substances are obliged to provide labels in accordance with the
NOHSC Code of Practice for the Labelling of Hazardous Substances (Labelling
Code) (NOHSC, 1994d).
In accordance with the NOHSC National Code of Practice (NOHSC, 1994b),
articles which give rise to hazardous substances during use, should be
appropriately labelled and indicate the conditions of use leading to the generation
of hazardous substance(s). As such, for the purpose of labelling asbestos-
88 Priority Existing Chemical Number 9
containing articles, items such as brake parts, clutches, gaskets and CAF sheets
should be labelled in accordance with NOHSC requirements.
In addition to NOHSC labelling requirements, requirements for labelling of
asbestos-containing wastes and construction materials should comply with the
NOHSC Asbestos Code of Practice (NOHSC, 1988) and the ADG Code for
labelling of chrysotile containing materials for the purposes of transport by
road/rail (see section 10.1.2).
NOHSC requirements for labelling of asbestos and asbestos products
Chrysotile is listed in the NOHSC List of Designated Hazardous Substances (the
List) (NOHSC, 1994c) and is classified as follows:
Concentration* of chrysotile Risk phrases
>10% R45; R48/23
>1% to <10% R45; R48/20
0.1 to <1% R45
* Refers to concentration of chrysotile (w/w basis) in a mixture. Raw chrysotile should
be classified as R45; R48/23.
R45 = May cause cancer (carcinogen category 1)
R48 = Danger of serious damage to health by prolonged exposure (R20 and R23 indicate
the critical route of exposure is inhalation)
The provision for inclusion of the Risk phrase R48 is to provide warning of the
potential for the non-carcinogenic effects of asbestos, primarily asbestosis. The
use of this Risk phrase in combination with R20 or R23 is to denote the critical
route of exposure for such effects (i.e., inhalation).
The List (NOHSC, 1994c) also recommends the use of the following Safety
phrases:
S22 = Do not breath dust;
S44 = If you feel unwell, contact a doctor or Poisons Information Centre
immediately (show label where possible); and
S53 = Avoid exposure - obtain special instructions before use.
Although the inclusion of Risk and Safety phrases is a requirement of the
Labelling Code, the Model Regulations stipulate only, that containers of
hazardous substances are appropriately labelled. As such the above risk and
safety phrases are not mandatory, provided adequate hazard and safety data are
included.
According to The List all substances (including hazardous articles) containing
chrysotile at and above 0.1% should be classified as `Toxic'. The Labelling Code
provisions permit the use of the (signal) word `Hazardous' as an alternative
and/or the ADG Code Class label 9 (Class 9).
Other information to be included on labels (for chrysotile/asbestos) as prescribed
by the Model Regulations and/or the Labelling Code are:
? Disclosure of the chemical name (e.g., chrysotile) - under the provisions for
Type I ingredients;
89
Chrysotile Asbestos
? UN number;
? Proportion of ingredients;
? Directions for use;
? Contact details of the Australian supplier; and
? Reference to an appropriate MSDS for further directions (on use and
handling etc.,).
Labels for raw chrysotile
Raw chrysotile should be labelled in accordance with the NOHSC Labelling
Code, the minimum requirements of which should include product/chemical
name; details of supplier; hazard category/signal word and/or ADG Code16 Class;
risk and safety phrase information and reference to the MSDS.
Labels for raw chrysotile were supplied by Bendix Mintex Pty Ltd, Richard
Klinger Pty Ltd and Vivacity Engineering. Labels provided appear to be based
on labelling guidelines produced by NHMRC (National Health and Medical
Research Council, 1982), in addition to relevant provisions of EEC Directive
76/769 (Anon, 1983). None of the labels complied completely with NOHSC
requirements. Bendix and Klinger labels, although containing warning of
potential hazards and safe handling instructions, did not contain the NOHSC
recommended hazard category/signal word or ADG Code classification and class
information. The label provided by Vivacity, although containing ADG Code
classification and class information, did not contain the NOHSC recommended
hazard category/signal word or adequate data on potential hazards and safe
handling.
None of the labels provided risk and safety phrases or a reference to the
appropriate MSDS.
It was pointed out by one applicant that some of the above information was
present in the Emergency Procedure Guide (EPG)17, provided by the freight
forwarding company, however, the EPG provided for assessment had not been
updated for over 10 years and was deficient with respect to hazard
category/signal word, ADG Code classification/class information, risk and safety
phrases or reference to the MSDS. In addition, it was considered (by NICNAS)
unlikely that EPGs would be provided to workers handling bags of raw
chrysotile.
It should be noted that raw chrysotile is imported and that apart from affixing the
standard (as recommended by EEC) label for asbestos and asbestos products (i.e.
`a' ?WARNING/ CAUTION CONTAINS ASBESTOS), the above companies
do not appear to re-label the imported containers/bags.
Labels for chrysotile products
A total of 14 labels for chrysotile products were obtained from the following
sources:
16
Additional information e.g. Hazchem Code (2X) and Packaging Group (III) are required by this
Code for the purpose of transportation by road/rail.
17
Emergency Procedure Guide 9B7 - White Asbestos - (AS 1678, March 1988).
90 Priority Existing Chemical Number 9
? a survey of the automotive aftermarket (see Survey 3 in Appendix 2) (5
labels);
? a survey of importers of chrysotile products (see Survey 1 in Appendix 2) (7
labels); and
? applicants (2 labels).
Labels were provided for chrysotile friction materials (brake blocks, brake disc
pads and brake linings), gaskets and CAF sheeting. No labels were provided for
clutch facings and automotive transmission discs. More than 5 labels were
sighted during the automotive aftermarket survey, however only 5 (representing
one for each product type) were analysed for this assessment. Bendix Mintex Pty
Ltd provided a label which it was claimed appears on the packaging of all
chrysotile containing products that they manufacture, as did Richard Klinger Pty
Ltd.
Table 23 presents a comparison of the information on the labels provided, with
some of the safety and health hazard information recommended by NOHSC.
Table 23 - Comparison of information contained on labels supplied
for chrysotile friction products and gaskets with
information recommended by NOHSC.
Brake Disc Drum Gaskets/
Recommended information
blocks brake brake CAF
linings1
pads sheeting
Total number of labels 1 5 3 5
Hazard category/Signal word:
`Toxic' or `Hazardous' 0/1 0/5 0/3 0/5
Recommended safety phrases and
directions:
Do not breath dust 0/1 0/5 0/3 0/5
If you feel unwell, contact a doctor or 0/1 0/5 0/3 0/5
Poisons Information Centre
immediately (show label where
possible)
Avoid exposure ?obtain special 0/1 0/5 0/3 0/5
instructions before use
Refer to MSDS for further directions 0/1 0/5 0/3 0/5
Recommended health hazard/risk
information:2
May cause cancer 0/1 2/5 2/3 3/5
Danger of serious damage to health by 1/1 5/5 3/3 5/5
prolonged exposure
Toxic by inhalation 3 0/1 5/5 3/3 5/5
1
Includes the Bendix Mintex generic label
2
actual phrases used on labels sometimes differed in wording, but were counted as complying where
the meaning was the same
3
No labels contained this phrase, however all except one indicated that inhalation was the critical
route of exposure by such wording as `Breathing asbestos dust may cause serious damage to
health.'
91
Chrysotile Asbestos
All labels had a general statement about the risk of serious damage to
health , however only half the labels contained a reference to the risk of
cancer. None contained the relevant signal word/hazard classification.
The labels, as supplied, were deficient in the recommended safety phrases and
directions. Some labels for brake pads and linings did contain important safety
directions, specifically, instruction to use a damp cloth when handling the product
and to not use an airline or brush to remove dust from brake drums (3/8). Most
labels also contained a direction to avoid creating dust or to keep dust down
(9/14).
It was noted that all of the labels contained a symbol for asbestos recommended
to be placed on labels by the EEC, in part 1 to Annex II of Directive
76/769/69/EEC (white `a' on black background). Four of the labels followed the
full EEC recommendations concerning this particular label, namely, the above
symbol together with the words: `Warning Contains Asbestos. Breathing
Asbestos Dust is Dangerous to Health. Follow Safety Instructions'. However, no
safety instructions were provided. It was observed during the automotive
aftermarket survey that safety directions are sometimes enclosed within the
packaging in the form of a pamphlet. A potential problem arising from this form
of labelling is unintentional discarding of safety directions with the packaging.
It was also noted that six of the labels were labelled in accordance with
NH&MRC guidelines issued in 1981, which recommended the following words:
`Caution. Contains asbestos fiber. Avoid Creating Dust. Breathing asbestos may
cause serious damage to health, including cancer. Smoking greatly increases the
risk.'
Some workers interviewed during the automotive aftermarket survey claimed that
there were some product labels for asbestos-containing friction products that did
not identify the presence of asbestos. These products originated from overseas
(e.g. India, Taiwan and Thailand) and the workers claimed they were able to tell
from appearance that the products contained asbestos.
Education and training
Guidelines for the induction and training of workers potentially exposed to
hazardous substances are provided in the NOHSC Model Regulations (NOHSC,
1994b).
All new employees of Bendix Mintex attend an induction program. They receive
information and training in regard to safe working with chrysotile. The induction
program covers health risks, potential routes of exposure, workplace control
mechanisms, safe work practices, personal protective equipment and specific
information on handling of chrysotile. Employees working in areas where there
is a mandatory requirement to wear respiratory protection are given training and
information on the correct use and selection of appropriate respirators.
Similarly, Richard Klinger employees involved in the handling of raw chrysotile
and chrysotile products are provided with a training program at the
commencement of employment. Employees required to wear respirators are
given training on how to use and maintain the respirators. Each employee is
supervised and receives "on the job training" regularly.
92 Priority Existing Chemical Number 9
Additionally Richard Klinger employees involved in the production of gaskets
receive training on safe working practices. All employees also receive training
on how to operate each item of plant or equipment.
From the responses to the questionnaire for end-users of chrysotile products, (see
Appendix 2) few workers received formal training on the hazards of asbestos and
precautions to be taken for safe handling. Most learnt about the health and safety
issues from `on the job' experience. In some workshops, it was reported that
workers, particularly younger workers, were educated in these issues during their
technical college training. One workshop reported that information was obtained
from industry magazines.
With regard to technical college training, NSW Technical and Further Education
(TAFE), Transport Industry Training Division provides training in their course on
Automotive Workplace Safety, Tools, Equipment and Practice. This course
covers light and heavy vehicle, motorcycle, marine and plant mechanics and
provides instruction and practical experience to enable workers to correctly use
and maintain automotive tools and equipment. The course provides an
understanding of automotive workshop procedures/practices including
occupational health and safety issues, which include those related to working
with asbestos.
Scheduled Carcinogenic Substances
The NOHSC Model Regulations for the Control of Scheduled Carcinogenic
Substances (NOHSC, 1995b) impose requirements over and above the provisions
of the NOHSC Model Regulations (NOHSC, 1994b) for certain carcinogenic
substances.
Chrysotile is a scheduled carcinogenic substance under these regulations, listed in
Schedule 2, as a notifiable carcinogenic substance when used for the manufacture
of asbestos products. Schedule 2 carcinogens are substances that have specific
limitations on their usage. Requirements of the regulations include:
? notification to the relevant public authority of any proposed use of chrysotile
for manufacturing products;
? a work assessment, including an assessment of potential exposure, to be
carried out prior to its use;
? the keeping of records of employees likely to be exposed;
? the reporting of exposure incidents to the relevant public authority; and
? advising employees of any accidental exposure.
Amosite and crocidolite are listed in Schedule 1 of the regulations as prohibited
substances, except for removal and disposal purposes and situations where they
occur naturally and are not to be used for any new purpose.
Monitoring and exposure standards
Air monitoring
Air monitoring is required for asbestos (including chrysotile) under the specified
provision of the NOHSC Model Regulations for the Control of Scheduled
Carcinogenic Substances (NOHSC, 1995b). Details of the methodologies
93
Chrysotile Asbestos
currently employed in the sampling and analysis of asbestos fibres (in air) are
provided in Section 4. Results from air monitoring studies (for asbestos) in
different Australian industry sectors are provided in Tables 8,9,11,13 and 14.
Australian exposure standard
The current national exposure standard (TWA) for chrysotile is 1 f/mL (NOHSC,
1988). This standard has been under review by the National Commission since
1993, following information (on the levels of lung cancer risk in various
industries) in a report presented by Rogers and Leigh, (1993). A public
discussion paper issued in December 1995 called for comment on three proposed
exposure standards; 1 f/mL, 0.5 f/mL, and 0.1 f/mL (NOHSC, 1995a), currently
adopted in different States/Territories. Public comment received for the draft
Proposed National Exposure Standard for the Occupational Environment for
chrysotile is currently being reviewed by NOHSC.
State/Territory exposure standards
National exposure standards are declared by the National Commission and serve
only as guidance. They have no legal status unless they are specifically
incorporated into Commonwealth, State or Territory legislation. The current
national exposure standard (1 f/ml TWA) has not been uniformly adopted by
State and Territories.
Table 24 - Current Australian State and Territory exposure standards
for chrysotile.
State/Territory Exposure limit
Australian Capital Territory 0.1 f/mL
Victoria 0.5 f/mL
New South Wales 0.5 f/mL (interim)*
All other States/Territories 1 f/mL
* pending review of the exposure standard by the National Commission.
Currently the lowest exposure standard for chrysotile is in the Australian Capital
Territory. Documentation for this standard (which has been in force since 1991)
was not available for this assessment, however it would appear (from available
transcripts of the Asbestos Advisory Committee) that the rationale for adopting
this level is related to the fact that the MFM for analysis of fibres does not
distinguish between chrysotile and other asbestos fibres (ACT Workcover, 1998).
As such a level of 0.1 f/mL, would protect against co-exposure to other forms of
asbestos (e.g., amosite, crocidolite) which have a national exposure standard of
0.1 f/mL. International exposure limits for chrysotile can be found in Section
10.2.2.
Health surveillance
Health surveillance is prescribed for asbestos (including chrysotile) under
provisions of the NOHSC Model Regulations for the Control of Scheduled
Carcinogenic Substances (NOHSC, 1995b) and Schedule 3 of the NOHSC Model
Regulations (NOHSC, 1994b).
94 Priority Existing Chemical Number 9
Health surveillance is required for employees who have been identified in the
workplace assessment process as having a significant risk to health from being
exposed to asbestos.
NOHSC has published guidelines for health surveillance for asbestos (NOHSC,
1995c), which sets out the minimum requirements, which comprise a medical
examination (at least every 2 years); and an occupational and medical history.
Respiratory function tests, chest x-ray and physical examination are not required
unless indications are present.
Bendix Mintex provides health surveillance for all relevant employees engaged in
the manufacture of asbestos products and associated support operations. This
program includes chest x-rays, pulmonary function tests (spirometry) and
physical examinations by a qualified medical practitioner.
At Richard Klinger, employees handling raw chrysotile are given a medical
examination after commencement of employment. Medical examinations include
chest x-ray and lung capacity tests (spirometry). Medical examinations are
conducted on a regular basis at intervals not exceeding three years.
Workshops involved in the end-use of friction materials and gaskets were not
specifically asked whether their workers were sent for regular medical check-ups.
However, two workshops indicated that their workers underwent a regular check,
including an x-ray and a lung function test.
10.1.2 Transportation regulation
Chrysotile (white asbestos), is classified in the Australian Code for the Transport
of Dangerous Goods by Road and Rail (the ADG Code) (FORS, 1988) in Class 9.
This category comprises miscellaneous substances that present a danger but
which are not covered by other classes. Under the ADG Code, chrysotile is
assigned to packaging group III.
The ADG Code sets out various requirements for the labelling, packaging and
surface transport of dangerous goods. With regard to chrysotile, it specifies the
marking of packages (of > 2 kg) with the shipping name `White Asbestos', Class
label 9, UN Number (UN 2590) and name and address in Australia of
manufacturer, agent or consignor of the goods. Freight containers containing
chrysotile must be marked with the UN Number and Class label and road vehicles
must be marked with Class label, unless more than one dangerous good is
present, in which case the mixed Class label is required (see ADG Code for
further details).
Dangerous Goods legislation, which makes reference to the ADG Code, has been
enacted in all States and Territories.
10.1.3 Environmental regulation
Environmental legislation in Australia relates primarily to asbestos waste and is
outside the scope of this report. There is no obligation on the original
manufacturer of an asbestos product to take back the product, however legislation
such as the Environmentally Hazardous Chemicals Act 1985 (NSW) obligates
workers using or removing asbestos and asbestos containing materials to dispose
of waste in accordance with prescribed requirements. Further information on the
95
Chrysotile Asbestos
safe removal of asbestos and control of asbestos hazards in buildings is available
in the NOHSC Code of Practice and Guidance Notes on Asbestos (NOHSC
1988).
10.1.4 Details of regulation in Australia
Regulation of chrysotile is complex, implemented in over 30 statutes and
regulations and involving at least sixteen occupational health and safety and
environment authorities (see Table 25). In addition, various local government
bodies may have specific requirements for particular activities (e.g., building and
construction works).
Although legislation does not generally distinguish chrysotile from other forms of
asbestos specific restrictions are sometimes imposed. For instance, the use of
amosite and crocidolite is prohibited in most jurisdictions, however the use of
chrysotile is not (see Table 26).
There is a difficulty with current legislation in that definitions of asbestos
`processes' vary between jurisdictions and it is sometimes unclear as to the extent
to which the use of manufactured articles is regulated as distinct from the process
of manufacture. This has particular importance when considering certain work
processes specific to chrysotile. For example, the definitions of "asbestos
process" and "asbestos material" in Western Australia are:
Asbestos process means:
Any manufacturing process involving the use or handling of asbestos or any
substance containing asbestos including:
a) the sawing, cutting and sanding of asbestos materials;
b) the repair, maintenance and replacement of asbestos surfaces;
c) the cleaning and disposal of asbestos material; and
d) the mixing and application of asbestos shorts, cement, grouts, putties and
similar compounds.
Asbestos material means:
a) loose asbestos fibre;
b) any material containing loose asbestos fibre for use in an asbestos process;
and
c) waste material containing asbestos fibre that has been collected in a work
place.
From these definitions it would appear that the installation (during vehicle
maintenance) and the use of a friction product (e.g., brake pad) containing
chrysotile would not be regulated as either an `asbestos process' or `asbestos
material'. The concept of `manufacturing' does not generally extend to
installation and replacement processes. The definition of `asbestos material' only
incorporates loose asbestos or waste material containing asbestos and does not
extend to products containing asbestos in a bound matrix.
96 Priority Existing Chemical Number 9
A different definition of `asbestos process' is found in The Victorian
Occupational Health and Safety (Asbestos) Regulation 1992, which provides that:
Asbestos process means:
a) the removal of asbestos containing material from a building, structure or
ship; or
b) the handling of raw asbestos or dry mixtures containing raw asbestos,
including storage, mixing, sieving, crushing and milling; or
c) the manufacture of articles containing asbestos cloth; or
d) all processes in the manufacture of articles containing asbestos including
guillotining, grinding, blanking, finishing and dispatch; or
e) a process which is likely to create airborne asbestos fibres in excess of 50%
of the exposure standard; or
f) the maintenance of plant, including dust extraction equipment, used in any of
the processes listed in items (a) to (e) above; or
g) laundering of asbestos-contaminated personal protective equipment
including respiratory protective equipment and personal protective clothing
This definition would not extend to replacement of chrysotile articles (e.g.,
friction materials or gaskets) in equipment unless that could be described as a
process likely to cause airborne fibres in excess of 50% of the exposure standard.
97
Chrysotile Asbestos
Table 25 - Main legislative instruments in Australian States and
Territories for the control of asbestos
State/ Legislation
Territory
Australian Capital Building Act 1972
Territory Dangerous Goods Act 1984
Occupational Health & Safety Act 1989
New South Wales Mines Inspection Act 1901
Construction Safety Regulations 1950
Factories, Shops and Industries Act 1962
Dangerous Goods Act 1975
Dangerous Goods Regulations 1978
Factories (Health and Safety - Asbestos Processes) Regulation
1984
Environmentally Hazardous Chemicals (Chemical Control Order for
Asbestos Waste) Act 1985
Occupational Health and Safety (Carcinogenic Substances)
(Transitional) Regulation 1994
Waste Minimisation and Management Act 1995
Occupational Health and Safety (Asbestos Removal Work)
Regulation 1996
Occupational Health and Safety (Hazardous Substances)
Regulation 1996
Occupational Health and Safety (Hazardous Substances)
Amendment (Carcinogenic Substances) Regulation 1997
Northern Territory Dangerous Goods Act 1980
Work Health (Occupational Health and Safety) Regulations 1996
Dangerous Goods Regulations (draft) 1998
Queensland Environmental Protection Act 1994
Transport Operations (Road Use Management) Act 1995
Workplace Health and Safety Act 1995
Workplace Health and Safety Regulations 1997, Part 11 - Specified
Dangerous Goods, and Part 13 ?Hazardous Substances
South Australia Dangerous Substances Act 1979
Dangerous Substances Regulation 1981
Environment Protection Act 1993
Occupational Health and Safety Regulations 1995, Part 4 -
Hazardous Substances
Tasmania Dangerous Goods Act 1976
Industrial Safety, Health and Welfare (Administration and General)
Regulations 1979
Dangerous Goods Regulation 1994
Victoria Occupational Health and Safety Act 1985
Road Transport (Dangerous Goods) Act 1995
Road Transport Reform (Dangerous Goods) Act 1995
(Commonwealth)
Road Transport Reform (Dangerous Goods) Regulations 1997
(Commonwealth)
Dangerous Goods (Transport) (Amendment) Regulations 1998
Western Australia Explosives and Dangerous Goods Act 1961
Health Act 1971
Occupational Safety and Health Regulations 1988
Health (Asbestos) Regulations 1992
Commonwealth Hazardous Waste (Regulation of Exports and Imports) Act 1989
Road Transport Reform (Dangerous Goods) Act 1995 (Cmwlth)
Road Transport Reform (Dangerous Goods) Regulations 1997
(Cmwlth)
98 Priority Existing Chemical Number 9
Table 26 - Prohibitions (absolute) on asbestos use in Australia
State/ Prohibitions Legislation
Territory
New South Amosite and crocidolite in a factory Factories (Health and Safety -
Wales manufacturing process. Asbestos Process) Regulations
1984 ?under Factories, Shops
and Industries Act 1962.
All uses of amosite, crocidolite, ,
fibrous anthophyllite, tremolite and Occupational Health and Safety
actinolite, except for the purposes of (Hazardous Substances)
Regulation 1996 - under
sampling or analysis, maintenance,
removal, disposal, encapsulation or Occupational Health and Safety
Act 1983.
enclosure.
Northern New applications of amosite, Work Health (Occupational
Territory crocidolite, actinolite, anthophyllite, Health and Safety) Regulations
1996 - under Work Health Act
tremolite.
1996.
Chrysotile must not be reused or
used in a `spray' process.
Queensland All uses of amosite crocidolite, Workplace Health and Safety
fibrous anthophyllite, tremolite and Regulation 1997 ?under
actinolite (except sampling, removal, Workplace Health and Safety
disposal etc). Act 1995.
Supply of second-hand asbestos
product for use in the workplace.
Chrysotile use in `spraying'.
Using a power tool or high pressure
water process to clean an asbestos
product.
Using compressed air to clean a
surface where asbestos is used.
South Use of product containing asbestos Occupational Health Safety and
Australia `other than chrysotile' prohibited, Welfare Regulation 1995 (Part
subject to certain exceptions. Not to 4) ?under Occupational Health
be installed as insulation. Safety and Welfare Act 1986.
Tasmania Crocidolite must not be used in a Industrial Safety Health and
manufacturing/work process. Welfare (Administrative and
General) Regulation 1979
(Regulation 241).
Victoria All amphiboles ?specifies amosite, Occupational Health and Safety
crocidolite, actinolite, anthophyllite (Asbestos) Regulation 1992
and tremolite ?must not be used in (Regs 12.13,16) ?under the
a work process (specifies textiles Occupational Health and Safety
(spinning or weaving); spraying and Act 1985
production) except for sealing,
encapsulation, enclosure or removal.
Western Crocidolite or amosite or products Occupational Health Safety and
Australia containing them must not be used in Welfare Regulation 1988 (Reg
a manufacturing/work process. Not 808).
to be installed as insulation.
Health (Asbestos) Regulations
Chrysotile must not be used in a
1992 ?under Health Act 1991
`spray' process.
Common- Crocidolite or amosite must not be Industrial Safety Health and
wealth used in a manufacturing/work Welfare (Administrative and
process. General) Regulation 1979
(Regulation 241).
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Chrysotile Asbestos
10.2 International and overseas regulation of asbestos
10.2.1 International initiatives
International Labour Organisation (ILO) Convention 162
ILO Convention 162 `Safety in the Use of Asbestos', adopted in 1986, was
endorsed by government, industry and union representatives from over 125
countries in July 1986. This Convention provides for a hierarchy of preventative
and control measures which include:
? the prescription of adequate engineering controls;
? the prescription of special rules and procedures for the use of asbestos (or
certain types of asbestos or products containing asbestos) for certain work
process;
? to protect the health of workers and where technically practicable, to replace
asbestos (or certain types of asbestos) by other materials or use alternative
technology, scientifically evaluated by the competent authorities as harmless
or less harmful; and
? total or partial prohibition of the use of asbestos or of certain types of
asbestos in certain work processes.
The Convention only calls for two specific prohibitions for i) crocidolite and all
products containing crocidolite, and ii) spray-on applications of asbestos. At least
18 countries have ratified this Convention, including Brazil, Bolivia, Canada,
Chile, Germany, Spain, Sweden and Uganda (The Asbestos Institute & Quebec
Asbestos Mining Association, 1993).
In Australia, South Australia and Queensland agreed to ratification in February
and April 1991 respectively. However, although gaining acceptance by the
Australian Labour Ministers Council (in October 1992) and the National Labour
Consultative Council (in September 1994), Australia has not as yet ratified this
Convention (Department of Industrial Relations, 1994).
European Union Directives
EEC Directive 83/477 on the protection of workers from the risks related to
exposure to asbestos at work (as amended by EEC Directive 91/382) prohibits the
application of asbestos by spraying and procedures involving low-density
insulating or sound-proofing material containing asbestos.
EEC Directive 91/659, adapting to technical progress Annex 1 to EEC Directive
76/769 on the approximation of the laws, regulations and administrative
procedures of the Member States relating to restrictions on the marketing and use
of certain dangerous substances and preparations prohibits the marketing/use of
amphiboles (crocidolite, amosite, anthophyllite, actinolite and tremolite) and
amphibole-containing products, and the placing on the market and use of certain
products containing chrysotile, including toys, paints and varnishes, catalytic
filter and insulation devices (for incorporation into catalytic heaters using
liquefied gas).
100 Priority Existing Chemical Number 9
EEC Directive 98/12, of 27 January 1998 adopting to technical progress Council
Directive 71/320/EEC on the approximation of the laws of member states relating
to the braking devices of certain categories of motor vehicles and their trailers,
prohibits the use of all types of asbestos in brake linings for vehicles under 3.5
tons This prohibition does not include disc brake pads, clutches or gaskets.
A number of EU countries take the view that prohibitions on the marketing and
use of asbestos should be based on agreements within the European Commission.
The European Commission is currently working on a total ban of asbestos and
expects there to be a qualified majority in support of such a ban for the supply of
chrysotile (with exemptions for essential uses).
Information on asbestos substitutes (alternatives) has been submitted to the EU
Scientific Committee (CSTEE) on Asbestos by member countries for decision on
the proposed ban. The proposed ban does not recommend the removal of
asbestos materials already in place e.g., building insulation and industrial gaskets,
provided that such materials are in `good condition'.
Helsinki report18
In January 1997, an international expert meeting was held in Finland (Helsinki) to
develop recommended policies for recognition, attributability and screening of
asbestos related disease. A major outcome of this meeting was a consensus on
attribution and screening guidelines for mesothelioma, lung cancer and
asbestosis, which included the following (Anon, 1997):
? brief, low level exposure was regarded as sufficient to cause mesothelioma;
? all fibres can cause mesothelioma, but amphiboles are more potent
carcinogens for the mesothelium;
cumulative exposure to 25 fibre-years (fibres.year/mL)19 is sufficient to cause
?br>
lung cancer;
? asbestosis is not a necessary prerequisite for lung cancer;
? for asbestosis, uniform standards of pathology based on the US CAP-NIOSH
system could be adopted;
? diagnosis should be based on radiology according to the ILO standards
(category 1/0 minimum);
? high resolution CT scanning should only be performed in selected cases; and
? screening programs are justified in selected groups as early detection can now
significantly improve the prognosis of lung cancer.
In Australia, State/Territory jurisdictions are actively considering whether
these criteria would prove useful for adoption nationally (Labour Ministers
Council, 1998).
18
Public comment received on the draft report indicated criticism of the Helsinki report (criteria)
on the basis of a number of issues including lack of representation of the broader scientific
community and the evaluation of available epidemiological data.
19
Equivalent to an average exposure of 1 fibre per mL (in air) for 25 years.
101
Chrysotile Asbestos
10.2.2 Country specific regulations
The majority of countries regulate asbestos by controlling its use, although
several countries have implemented bans or partial bans on asbestos and asbestos-
based products.
Details of relevant legislation (relating to restrictions on asbestos) in Austria, ,
Denmark, France, Germany, Italy, Netherlands, Norway, Sweden, Switzerland,
United Kingdom and United States were obtained from the appropriate
authorities. An analysis of this legislation (by country) is provided in Appendix
7.
Prohibitions
From the information available, no countries have implemented an absolute ban
on the use of chrysotile (or chrysotile products), as current regulations contain
either specific exemptions (for specific applications) or a general exemption
provision (requiring permission from relevant authorities) or licensing
requirements for import and/or sale.
Prohibitions generally relate to `asbestos and asbestos-containing products'
(preparations or articles) in one or more of the following categories/activities20:
? use;
? placing on the market;
? sale;
? manufacture; and
? import/export.
For the purpose of prohibition, chrysotile is generally included in the legal
definitions of asbestos, although in some countries, the amphibole group
(crocidolite, amosite, anthophyllite, actinolite and tremolite) is subject to specific
regulation. This is the situation in Austria, which bans the manufacture, placing
on the market and use of asbestos and asbestos products of the amphibole group,
and 17 classes of products containing chrysotile. By contrast, countries that have
included chrysotile in general bans on asbestos and asbestos-containing products
include Germany, Norway, France and Switzerland.
Other countries, the UK in particular, take the view that prohibitions on the
marketing and use of asbestos should be based on agreements with the EU. The
Asbestos (Prohibitions) Regulations 1992, implements Directive 91/659/EEC and
prohibits the importation and use of many forms of asbestos. Under this
regulation, chrysotile is still permitted for any use other than those listed in the
Schedule to this regulation. As a result of this, friction materials and gaskets
made from chrysotile are still allowed in the UK. Since 1992, the UK policy has
been to work with the EU to seek to ban supply of chrysotile, with exceptions for
genuinely essential uses where safe and effective alternatives cannot be found.
20
France also includes on its list of prohibited activities `possession for the purpose of sale' and
`all manner of transfer'.
102 Priority Existing Chemical Number 9
In the United States the responsibility for preventive actions to reduce human
exposure to asbestos is held by the Environmental Protection Agency, and in
particular its program Office of Pollution Prevention and Toxics (OPPT).
Asbestos, including chrysotile, is controlled through various regulations issued by
the EPA and other government agencies.
The US EPA Asbestos Ban and Phase-Out Rule (and Court decision)
The EPA promulgated the Asbestos Ban and Phase Out Rule on July 12, 1989,
under section 6 of the Toxic Substances and Control Act (TSCA). This rule
imposed phased bans on the manufacture, importation, processing and
distribution in commerce of almost all asbestos products, and required labelling
of those products still in commerce as the phase out progressed. Friction
products, most gaskets, clutch facings, brake linings and disc brake pads for light
and medium weight vehicles were included in the bans. New uses of asbestos
were also banned [54 FR 29460; 40 CFR part 763].
In 1991 the US Court of Appeals (fifth hearing) voided21 most of the Rule on the
basis that the EPA had failed to comply with certain conditions of rulemaking
under TSCA, in particular, that they had failed to show that the products banned
by the Rule presented an unreasonable risk and that a less burdensome regulation
would not adequately protect against that risk. In particular the Court stated that
the EPA has failed to evaluate the harm that may result from increased use of
substitute products, many of which contained carcinogens. The Court also noted
that EPA had failed to study the effect of non-asbestos brakes on automotive
safety and mentioned the credible evidence that non-asbestos brakes could
significantly increase the number of highway fatalities. A clarification
subsequently issued by the Court established that asbestos-containing products
that were not being manufactured, imported or processed at the time of the Rule
continued to be subject to the Rule. It was subsequently determined that six
classifications of asbestos products fell into this category: corrugated paper,
rollboard, commercial paper, specialty paper, flooring felt, and new uses of
asbestos (58 FR 58964; 40 CFR part 763; Asbestos Institute Home Page, 1988).
Actions taken by the OPPT to reduce sources of asbestos since then include
regulatory and non-regulatory initiatives. For example, the EPA drafted a
voluntary agreement with 44 motor vehicle manufacturing companies to phase
out and discontinue use of asbestos-containing parts in the production of new
motor vehicles, however an issue as to whether the agreement would be
permissible under anti-trust laws meant the agreement did not go ahead.
Subsequently the EPA conducted a survey of the same companies which
indicated that most motor vehicle manufacturers either had already or expected to
phase out the use of asbestos altogether by 1999 (Cestone & US EPA, 1996).
Exemptions
Countries that have banned asbestos with exemptions include; Belgium,
Denmark, France, Germany, Holland, Italy, Norway, Poland, Sweden,
Switzerland and USA. Exemptions usually take the form of an annex or
appendix, which lists those classes of products which are exempt. In some cases,
21
The US Court of Appeals decision was based on the statutory "unreasonable risk" test.
103
Chrysotile Asbestos
there is also a non-specific clause allowing for a government authority to grant
exemptions on application.
Chrysotile products are the most common exemptions from the bans. In some
cases, the exemptions are time-limited, with a phase-out date specified, and often
further qualified, for example, applying only to devices for heavy industrial
equipment.
Friction materials and gaskets are the most common class of product exempted.
The exemption for these materials is usually qualified by a provision that no
suitable (i.e., less harmful and capable of assuring equivalent technical safety)
alternative material is available. Table 27 lists the current status of prohibitions
relating to asbestos/chrysotile containing friction products and gaskets in the
countries assessed in Appendix 7.
Other classes of chrysotile products exempted under various legislation include:
replacement parts for maintenance purposes; diaphragms for electrolytic
processes; sewage and pressure pipes; well casings for drainage in mining; porous
compounds for acetylene bottles; protective clothing for handling molten masses
of >1000 deg C; thermal isolation devices used in industry when dealing with
temperatures >600 deg C; seals and linings used for watertightness in industrial
processes when circulation of water at high temperature or pressure poses two of
the following risks: fire, corrosion, toxicity.
Table 27 ?Current status of prohibition of asbestos-containing friction
materials and gaskets (by country)
Country Product Prohibition/exemptions Comments
Austria Asbestos brake and Prohibited from being placed Government issues list of
clutch linings for on the market (incl. vehicle types, for which
vehicles manufacture & use), if the non-asbestos parts are
technology and road laws available.
allow the use of linings Information provided by
without asbestos and if such the Publication of this list
linings are available. has apparently ceased as
there are no cars needing
brakes or clutches made
with asbestos.
Legislation enacted in
1990
Criteria for (c) are a
Denmark Friction materials Prohibited for use in:
manufacturer's
(containing max 70%
declaration or a test
asbestos) (a) motor vehicles, trailers
report from an approved
and technical
testing laboratory.
equipment fitted with
non-asbestos original
In 1993 a list of `old' cars
equipment.
which may still be
(b) all new cars (from
equipped with asbestos-
1988).
free linings was issued.
(c) motor vehicles, trailers
and technical
equipment where
suitable alternatives are
available (from 30 June
1988).
104 Priority Existing Chemical Number 9
Table 27 ?Current status of prohibition of asbestos-containing friction
materials and gaskets (by country) (cont.)
Country Product Prohibition/exemptions Comments
Denmark (cont.) Asbestos-containing Prohibition date: 30 June
friction materials for 1989.
lifts.
Asbestos or asbestos- Exemption (`until further
containing (except notice') for manufacture,
crocidolite and import or use.
amosite) bonded Prohibited for gaskets used
gasket materials for water systems with a
temperature of under 110
deg C.
Exemptions to be
Exemption until 1 January
France Friction linings for
reviewed annually.
1999.
heavy industrial
equipment and
installations, certain Importer/introducer must
machines and heavy make annual declaration
vehicles. to the Minister for
Friction components Employment in relation to
for compressors and activities involving listed
vacuum pumps with exempt articles.
pallets.
Second hand vehicles Exemption until 31 Dec
or specified vehicles in 2001.
place at 1996
Friction linings for Exemption until 1 January
aircraft and seals and 2002.
linings used in
industrial processes of
high temperature or
pressure.
Prohibition date: 31 Prohibitions do not apply
Germany Clutch linings for
December 1992 - except to asbestos preparations
vehicles.
where no asbestos-free and products
alternatives are available manufactured before 14
from a safety perspective. October 1993.
Prohibition date: 31 Legislation enacted in
Brake shoe inserts for
December 1994 - except 1986
rail vehicles and
where no asbestos-free
friction pads for
alternatives are approved
industrial applications.
under transport legislation.
Exemption for brake linings
Cylinder head gaskets
in old lifts and lorries (no
for vehicles and
time constraint)
industrial use.
Prohibition date: 27 March
Italy Friction gaskets for
1994
motor vehicles,
industrial machines
and plant.
105
Chrysotile Asbestos
Table 27 ?Current status of prohibition of asbestos-containing friction
materials and gaskets (by country) (cont.)
Country Product Prohibition/exemptions Comments
Friction gaskets, spare Prohibition date: 27 March
Italy (cont.)
parts for railway 1995.
vehicles, industrial
machines and plant
with special technical
characteristics. Gasket
heads for older type
motor vehicles.
Dynamic gaskets for
stress components.
Netherlands Asbestos, (except blue General exemption where As a result of an inquiry
asbestos) containing for such vehicles, no into the availability of
friction materials asbestos-free friction asbestos-free friction
(production, materials are available. materials for vehicles, the
application and supply) government is
for heavy (>3500 kg) General exemption where considering extending the
motor vehicles these vehicles were ban to include heavy
(velocity < 50 km/hr), introduced onto the market vehicles.
and for vehicles <3500 before October 1 1985.
kg with velocity > 50 Legislation enacted in
km/hr. 1991.
Norway Friction components Prohibited where it is The government has also
and gaskets. impossible to manufacture indicated that most
or use products of this kind vehicles, both new and
with a content less harmful older models, are now
to health. fitted with asbestos free
friction linings. A list of
vehicles in which may
use friction linings
containing asbestos was
published by the
Norwegian National
Association of Car
Importers in 1993.
Prohibits for friction A special statutory
Sweden Asbestos-containing
materials (when offered for instrument lists vehicles
friction linings and
sale or transfer) in: manufactured prior to
gaskets.
these dates for which
(a) passenger cars and asbestos-free friction
motor cycles classed as linings are available.
1988 or subsequent
models for registration; Asbestos and material
containing asbestos may
(b) lorries and buses be used by permission of
classed as 1989 or the National Board of
subsequent models for Occupational Safety and
registration inspection Health if it is not possible
or type inspection; for less deleterious
material to be used.
(c) other motor-powered
vehicles and trailers
manufactured from 1st
July 1988 onwards.
Exemptions: Exemptions do not apply
to crocidolite and
materials containing
Brake linings and other
crocidolite
frictional elements
containing asbestos may be
used, machined/processed
106 Priority Existing Chemical Number 9
Table 27 ?Current status of prohibition of asbestos-containing friction
materials and gaskets (by country) (cont.)
Country Product Prohibition/exemptions Comments
and treated if no acceptable
Sweden (cont.)
products of less deleterious
material are available. Frictional elements must
be handled so that the
Gaskets may be fitted to emission of asbestos
engines manufactured dust is prevented
before 1987 if no acceptable
products of less deleterious
material are available.
Switzerland Friction linings for Prohibition date: 1 January Legislation enacted in
motor vehicles, 1992 (replacement parts & 1986.
machines and new vehicles)
industrial plants. Special construction
conditions are defined as
Spare friction linings Prohibition date: 1 January cases where replacing a
for motor vehicles, rail 1995 part containing asbestos
vehicles, machines by an asbestos-free
and industrial plants Spare parts containing spare part would involve
with particular design asbestos may continue to be making alterations to
conditions; cylinder exchanged for spares also other components of the
head gaskets for older containing asbestos in system concerned as
types of engine. vehicles with "special regards dimensioning or
construction conditions" materials.
Gaskets and other Prohibition date: 1 January
parts in new motor 1995 (gaskets) and Jan
vehicles. 1990 (other).
UK Friction materials such All amphibole asbestos The UK Health and
as brake and clutch containing products are Safety Commission has
linings, and gaskets. prohibited. submitted (Sept 98) a
recommendation to the
Chrysotile-containing Secretary of State to
products not prohibited extend the scope of the
under current legislation. existing UK legislation
(1992) on asbestos to
In relation to chrysotile, the cover all uses (including
current prohibition does not marketing and supply) of
apply to the use of any chrysotile, except for a
product which was in use limited number of
before 1 January 1993 essential uses where
unless it was subject to there are no satisfactory
prohibition by the Asbestos alternatives available.
(Prohibitions) Regulation of
1985. Legislation enacted in
1992.
USA Friction materials and Not prohibited under current Legislation (ABPO rule)
gaskets. legislation. enacted in 1989.
Intended to phase-out
asbestos products by
1996.
Court voided much of the
ABPO Rule in October
1991, leaving only certain
items as banned.
Source of data: Appendix 7
107
Chrysotile Asbestos
International exposure limits for chrysotile
Occupational exposure limits adopted by other OECD countries and other
international organisations are listed in Table 28.
Table 28 - International exposure limits for chrysotile
Country Exposure limit (f/mL)
2
Austria 0.25
2
Belgium 0.5
2
Canada 2.0
Denmark2 0.3
2
Finland 0.5
France2 0.6
Germany1 No MAK value established because chrysotile is
classified as a Group A1 carcinogen
Greece2 1.0
2
Ireland 0.6
Italy2 1.0 (8-hour TWA)
Japan1 0.5 (8-hour TWA)
2
2.0
Mexico
2
Netherlands 1.0
2
1.0 (4-hour TWA)
New Zealand
6.0 (maximum concentration over 10 minute period)
Portugal2 1.0
Spain2 0.6
1
0.2 (8-hour TWA)3
Sweden
2
Switzerland 1.0
Turkey2 5.0 (processing industry)
2.0 (mining)
UK1 0.5 MEL (4-hour TWA)
1.5 STEL (10 minutes)
US1 0.1 (8-hour TWA)4
European 0.6 (8-hour TWA)
Community1
ACGIH1 2.0 (8-hour TWA)
1
overseas limits for which documentation is available.
2
source: Asbestos International Association, United States (May 1994).
3
all forms of asbestos except crocidolite.
4
includes all asbestos fibres.
10.3 Compliance issues
NICNAS sought information from a number of other countries on their
experience with phase-out of asbestos products. This was in response to industry
raising the issue of the compliance measures needed to control illegal import. To
date Germany, Switzerland, Norway and Denmark have responded.
Switzerland indicated that non-compliance may occur in rare circumstances (e.g.
direct import of roof-sheets) and is not a major problem. Illegal importers risk a
fine and in some instances may be brought to trial.
108 Priority Existing Chemical Number 9
Germany has no information on this issue but stated that illegal import is highly
unlikely to occur as all new vehicles in Germany now have asbestos-free
components.
Norway advised of some (minor) problems regarding the illegal sales of asbestos
containing friction linings. In 1993 and 1994 the Norwegian Government
controlled this problem in certain retail groups.
Danish authorities advised that various elements in their existing regulations
would impede a trend to illegal imports of asbestos, notably the labelling
provisions of the EC Directive. Furthermore, it was believed that generally, there
is a keen interest in asbestos related issues and worker representatives on safety
councils are aware of this issue (illegal import).
While this information is indicative of the countries' experience, clearly the
effectiveness of any controls is dependent on the implementation of the necessary
appropriate compliance and enforcement measures.
109
Chrysotile Asbestos
11. Asbestos Alternatives
11.1 Background
The past decade has seen considerable activity in the development of alternatives
for asbestos containing products and there are a number of substitutes in current
use. Alternatives may be inorganic or organic, fibrous or non-fibrous and natural
or synthetic. The majority of asbestos substitutes are mixtures of materials that
exhibit similar characteristics to chrysotile under specific conditions of use (Virta,
1992).
There are a number of issues surrounding the development and use of alternatives
to asbestos products, which include performance, cost and safety. The main
issues of concern with respect to regulatory mechanisms are potential health and
environmental risks and quality and performance assurance of alternative
materials.
The following sections of the report review available information on asbestos
alternative materials in current use overseas and in Australia, together with the
known health effects of some of these alternatives. In addition, pertinent safety
and regulatory issues associated with the use of non-asbestos alternatives are
considered.
It is beyond the scope of this report to assess the suitability (with respect to
performance and/or health effects) of specific alternative materials. Selection of
alternatives for a particular use is the responsibility of manufacturers and
importers/suppliers and should be carried out in accordance with existing
State/Territory regulation and relevant guidelines/standards.
11.2 Use of alternatives overseas
Asbestos alternatives are used in many products overseas, including; beater-add
gaskets, sheet gaskets, roofing felt, cement pipe, cement sheeting and shingles,
friction materials (e.g. brake linings, disc brake pads, brake blocks, clutch
facings), millboard and roof coatings. Alternatives in place for these uses
include; aramid, para-aramid, moulded aramid, fibreglass,
polytetrafluoroethylene (PTFE), polyethylene, polyvinylchloride (PVC) and vinyl
compositions, semi-metallics, steel fibres, ductile iron, aluminium siding,
carbon/graphite, cellulose, refractory ceramic fibres, phoshate, asphalt, tile, mica,
wollastonite, fibreglass and other mineral fibres (Environmental Protection
Agency, 1989; Virta 1992).
11.3 Use of alternatives in Australia
Alternatives have been developed for most uses of chrysotile in Australia. Based
on known past uses of asbestos and NICNAS surveys of current uses, it was
evident that alternatives have replaced chrysotile to a large extent in the following
products in Australia:
110 Priority Existing Chemical Number 9
Products where chrysotile has been completely replaced:
? cement sheeting, tubes and piping
? roofing tiles
? textiles
? fibre insulation
? railway brake blocks
? brake disc pads in new automotive vehicles (only 1 new vehicle model was
identified as being supplied with asbestos pads in Australia)
Products where a major proportion of chrysotile use has been replaced:
? clutch facings (in automotive vehicles and industrial machinery e.g. tractors,
centrifuge drives)
? brake disc pads (in older taxi and courier vehicles, and industrial machinery)
? gaskets, such as spiral wound and head gaskets
? washers
? packing material
? rotor blades (e.g. in high vacuum pumps)
Investigations show similar trends in other developed countries.
Some industries have replaced asbestos totally. For example, Futuris Industrial
Products, who supply non-asbestos products to the railway industry indicated that
alternatives already in place include: cotton, cellulose, wollastonite, aramid
(kevlar) fibres, steel, carbon and glass and mineral fibre (personal
communication, 1995). Futuris also reported that nearly all manufacturers in the
railway industry have now converted to asbestos-free parts.
Other industries have chosen to redesign their equipment. For example, NSW
State Railway have eliminated the use of asbestos in certain railway applications
by redesign of certain equipment/structures e.g., the elimination of friction
material in the bogie.
11.4 Friction material alternatives
Friction products comprise brake linings, brake disc pads, brake blocks22 and
clutch facings.
The most important physical properties that chrysotile imparts to these products
are:
? heat resistance;
? low heat conductivity;
? durability; and
? high friction coefficient
22
Brake blocks were commonly used in heavy vehicles and the railway industry.
111
Chrysotile Asbestos
Therefore, alternative materials should possess these properties to the level
required for efficacy/performance, in addition to presenting a lower level of risk
to human health. In considering replacements, cost will also be a consideration.
Chrysotile is relatively low in cost, however, with the increased volume and
availability of non-asbestos alternatives, it is envisaged that cost differentials will
eventually be reduced.
ASME lists four types of non-asbestos materials most commonly used in friction
materials (ASME, 1988). These are:
? non-asbestos organic (NAO);
? resin-bonded metallic (semi-metallic);
? sintered metallic; and
? carbon.
International research into alternatives for asbestos friction products has led to the
development of a number of alternative materials that are claimed to exhibit equal
or higher performance standards to chrysotile. There are currently no universal
alternatives suitable for all applications and in many cases, particularly brake
parts, they are only suitable for the specific braking system for which they were
developed (ASME 1988; Anderson 1995). However, Baker (1992) reports that
there are alternatives available for most applications (i.e., disc brake pads, drum
brakes and clutch facings for cars and commercial vehicles,) which either match
or exceed both physical and friction properties of their asbestos-based
counterparts.
Table 29 provides further details on some alternative materials reported in the
literature. Table 30 provides detailed information on the advantages and
disadvantages (for use in friction products) for some of these materials reported
by Hodgson et al. (1989). A more recent source of this type of information was
not available.
112 Priority Existing Chemical Number 9
113
Chrysotile Asbestos
114 Priority Existing Chemical Number 9
11.4.1 Road safety issues associated with replacement of chrysotile
with non-asbestos materials in friction products
Excepting the considerable amount of work being carried out on the health effects
of asbestos alternatives (see Section 11.7), little research appears in the literature
regarding road safety issues in relation to replacement of chrysotile with non-
asbestos friction products.
A study carried out on behalf of the US EPA in 1988 by ASME Centre for
Research and Technology Development (ASME 1988) looked at the feasibility of
replacing asbestos with alternative materials in automobile and truck braking
systems, which included an assessment of the impact on road safety. The main
finding of this study was that substitution of non-asbestos material in either
vehicle disc pads or drum linings may have an adverse effect on vehicle brake
balance and controllability, and that drum brakes in particular may exhibit
significant differences in effectiveness.
It was concluded that mandating an industry wide substitution of non asbestos
friction materials for aftermarket vehicles, originally equipped with asbestos-
based linings, could lead to a potentially serious safety risk unless stringent
friction material qualification/specification tests were first undertaken. Further
studies were recommended, however it is not known whether these took place. It
was proposed to first conduct a study to determine aftermarket vehicle classes
and brake system designs, with the aim of identifying the major vehicle
populations with respect to the key properties (for purposes of replacement of
friction materials) of weight range, brake design, and front-to-rear braking
balance. Dynamometer tests and vehicle performance tests of non-asbestos
materials (to determine friction product effectiveness under vehicle service
conditions, and compliance with existing vehicle performance standards) could
then be targeted at the most common classes of vehicles identified (Fletcher et al.,
1990).
According to the Australian Federal Office of Road Safety (FORS), no studies
have been carried out on the feasibility and/or impact on road safety of replacing
asbestos with alternative friction materials in Australia. (FORS, 1998). However,
FORS in conjunction with the National Road Transport Council have developed
safety standards (e.g., ADRs) that have been adopted as national standards under
the Federal Motor Vehicle Standards Act 1989 (see Section 11.5). General road
safety issues associated with the aging Australian vehicle fleet has also been the
subject of recent research (see Section 11.5.3), which would require consideration
in any impact study.
11.4.2 Use of alternative materials in friction products in Australia
Bendix Mintex are the largest manufacturers of friction products in Australia
producing both asbestos and non-asbestos products. Some of the alternative
materials used by Bendix Mintex for friction materials are aramid fibres,
fibreglass, semi-metallic, mineral wool, steel wool, wollastonite, and refractory
ceramic fibres (RCF).
Investigations through industry surveys showed there are many alternatives in
place for friction materials. For example in the railway industry asbestos brake
blocks have been replaced with glass fibre pads. In the automotive industry, for
115
Chrysotile Asbestos
motorcycles the alternatives in place for brake disc pads, brake shoes and clutch
facings include aramid fibre, stainless steel, paper and cork. For automotive
vehicles the alternatives in place for brake disc pads and clutch facings include
aramid fibres, fibreglass, carbon/graphite, semi-metallic, mineral wool, steel
wool, wollastonite, cellulose (A/T), refractory ceramic fibres and titanate fibres.
Investigations have shown that most of the clutch facings now come in a kit form,
the majority of which are non-asbestos. No information was provided on the
types of non-asbestos material(s) used in clutch facings.
New vehicle industry
All but one new vehicle model (Ford Utility with asbestos rear brake lining) on
the Australian market have all non-asbestos friction components (see Section 5).
Details of a NICNAS survey of companies importing/manufacturing new vehicles
can be found in Appendix 2. Data indicates that the Ford Utility comprises <1%
of total vehicle sales for the year 1996.
Most companies have manufactured and imported asbestos-free (including
friction products and gaskets) vehicles for several years. Table 31 gives details of
when the top 10 companies in Australia converted to using non-asbestos
components in their new vehicles.
Table 31 - Introduction of non-asbestos components by top 10
importers/manufacturers in Australia.
Year in which company converted to non-asbestos
Company
components
Ford Laser: Brakes 1989
Clutch 1990
Mondeo: asbestos free from introduction in 1995
Falcon/Fairlane: 1994 - 1995
Louisville: asbestos free from 1992 onwards
Probe: asbestos free from introduction in 1996
Holden All current models are asbestos free, year of conversion not
specified.
Toyota Australia Introduced non-asbestos products into new vehicles 4-5 years
ago.
Mitsubishi Motors Australia Introduced asbestos-free from late 1980s to early 1990s.
Production of vehicles requiring asbestos gaskets concluded in
December 1996.
Hyundai Always asbestos-free. Company started importing vehicles in
1994.
Nissan Motor Company Started using non-asbestos components in 1991
Mazda Australia First implemented non-asbestos components in 1986 for
specific uses and came into full effect gradually in 1990.
Honda Took action to discontinue usage of asbestos in its products in
April 1991. Conversion to non-asbestos products was
completed in July 1994.
Daewoo Always asbestos free. Daewoo started operation in Australia in
September 1994.
Subaru Converted to non-asbestos components in 1989.
116 Priority Existing Chemical Number 9
Vehicle aftermarket
As stated above, most new vehicles are now manufactured with non-asbestos
original parts, and therefore, there are non-asbestos replacement parts available
for these vehicles.
Several companies in Australia also manufacture/import non-asbestos products
for the aftermarket. A NICNAS survey indicated that non-asbestos replacement
friction products are available for around 90% automotive models.
For the specialised use of friction products in the aftermarket, several catalogues
are available to assist service garages to identify correct parts. Bendix Mintex
produces a catalogue which lists specific models of cars and the type of products
available (e.g. asbestos, or non-asbestos brake disc pads or brake linings) (Bendix
Mintex Pty Ltd, 1996/97). The catalogue is used by garage mechanics to identify
suitable product for a particular vehicle type.
According to Bendix Mintex, the catalogue accounts for approximately 90% of
vehicle models present in Australia and lists non-asbestos alternatives for most
vehicles manufactured in the last 20 years. Bendix Mintex also provided
NICNAS with a listing of vehicle models not covered in their product range and
indicated that manufacture/import of suitable friction products for these models
may have ceased due to the company policy of deleting `low volume' parts from
their product range.
Bendix Mintex manufacture two types of non-asbestos disc brake pads:
? semi-metallic (Brand names: Metal King Plus, Taxi Pack)
? low metal (Brand name: Ultimate).
The semi-metallic disc brake pads are particularly suitable for taxis, couriers ,
4WD, front wheel drive and large passenger cars. They are recommended for
active and frequent braking driving styles. Low metal disc brake pads are
available for a more limited range of vehicles, in particular sports, performance
and prestige vehicles.
The catalogue also includes a cross-reference section which provides information
about parts from overseas suppliers and corresponding products available from
Bendix Mintex. Also contained in the catalogue are data sheets which detail the
driving style best suited to each material.
Similar catalogues are also available from other companies, such as National
Brake and Clutch Pty Ltd (NBC). NBC only manufacture semi-metallic friction
products.
Although non-asbestos products are available for most vehicle types, they are
often not used in the aftermarket. Asbestos products continue to be used in
vehicles with non-asbestos original equipment. The `Automotive Aftermarket
Survey' identified some of the reasons for the continued use of asbestos products
in the replacement aftermarket (see Appendix 2). Some of the reasons stated in
the survey were:
? Poor quality and performance of non-asbestos products e.g. Bendix Mintex
reported deficiencies in a number of imported non-Japanese Asian products,
where test results (under normal braking conditions) included delamination
117
Chrysotile Asbestos
and cracking/crumbling of friction material; insufficient stopping distances
and failure of fade tests;
? Alternatives not available for some applications because market too small to
manufacture non-asbestos products for some applications;
? Non-asbestos friction products are not as durable (wear faster) as chrysotile
products;
? Non-asbestos pads smell and are noisy when braking and produce a lot of
dust;
? Non-asbestos products are more expensive;
? In buses, alternatives not used because of vehicle specification e.g. old buses
manufactured only to take chrysotile products; and
? Lack of regulation of the aftermarket industry.
11.5 Safety assurance/regulation of friction products
11.5.1 New vehicle market
The Motor Vehicle Standards Act 1989 provides for uniform national vehicle
safety, emissions and noise standards for vehicles entering the Australian market
for the first time. Under this Act, Australian Design Rules (ADRs) have been
endorsed as national standards. ADRs were initially developed under the
auspices of the Australian Transport Advisory Council between February 1983
and December 1986, and are periodically added to and amended, by the Federal
Office of Road Safety in conjunction with the National Road Transport
Commission, vehicle manufacturers, operators, consumer groups and road safety
experts. There are a number of ADRs relating to brake systems - in passenger
cars (ADR 31/00), motorcycles and mopeds (ADR 34/00), commercial vehicles
(ADR 35/01), and trailer brake systems (ADR38/02). These ADRs prescribe
performance tests designed to test the overall safety of the braking system as a
whole, and do not specifically address safety aspects of individual components.
11.5.2 Vehicle aftermarket
A draft Australian Standard for testing aftermarket disc pads for passenger
vehicles was released by Standards Australia for public comment in October 1997
(Standards Australia, 1997). The final standard, AS 3839-1998 Evaluation of
aftermarket disc pads for passenger vehicles and their derivatives, was due for
publication in September 1998.
The draft standard sets out the recommended minimum requirements for the
quality and performance of disc pads sold in the Australian aftermarket. It
specifies the tests required and the equipment to be used in performing the tests.
The objective of the standard is to ensure that the product is suitable for:
? fit;
? function; and
? performance for each application of the aftermarket disc pads.
118 Priority Existing Chemical Number 9
According to the draft standard, two types of tests should be conducted: a bond
plane shear test and a dynamometer performance test, the latter to be in
accordance with recommended practice contained in the Society of Automotive
Engineers' (SAE) standard J1652. Where the same disc brake pad is intended to
suit different vehicles, it is proposed that all vehicle configurations be tested. The
draft also draws attention to the fact that it is the responsibility of the
manufacturers/importers/supplier of the brake pads to ensure the suitability of the
product.
No Australian Standard(s) exist for other brake components (e.g., drum brake
linings).
Bendix Mintex report that all brake products are tested for each vehicle type
before being listed in their catalogue, except for some vehicle models where
braking systems are virtually the same and therefore do not require testing.
Testing carried out by Bendix Mintex include dynamometer and computerised `in
vehicle' data acquisition system testing. Field tests are carried out and in most
cases the test product is given to garages, taxi companies and rental car
companies for trialing. After the product has been tested by these companies they
provide feedback to Bendix Mintex via a formal performance report.
NBC report that testing and re-testing are key procedures in each stage of
manufacture. This testing is measured against tolerances which ensure complete
conformance to standards and performance characteristics. This applies to both
the raw materials received from suppliers and products produced.
Field and laboratory testing is undertaken on all the NBC product range. NBC
has also undertaken and gained accreditation from two industry-recognised test
procedures:
? Australian ADR 31 design rules; and
? US Vehicle Equipment Safety Commission V-3 regulations.
NBC report that the main difficulties with regard to testing products are the lack
of standards to test against in the aftermarket. Although car manufacturers have
to meet ADR 31 prior to placing a car on the market, the nature of the testing
requirements (e.g. use of dynamometer) for ADR 31 is such, that compliance
with this standard in the aftermarket is not readily assessable and as such is
considered unlikely to be enforced.
11.5.3 General safety and other issues of aging car fleet
Recent research has highlighted some of the safety aspects of an aging car fleet.
Two recent studies by CSIRO and Monash University Accident Research Centre
found a direct relationship between vehicle age and mortality/morbidity rates and
accident potential. More details of these studies can be found in Appendix 9.
The Australian Automotive Association cites road safety, emissions performance,
fuel consumption and vehicle theft as the main issues of relevance to the aging
car fleet. The AAA maintain that policies which encourage the updating of the
car fleet and recycling of older vehicles will have substantial safety and economic
benefits and have recommended a number of possible initiatives in this regard
(AAA, 1998).
119
Chrysotile Asbestos
It was noted that a number of countries have stringent vehicle inspection and
retirement regulations in place to control the extent of the aging car fleet.
11.6 Gasket material alternatives
Gaskets are used to seal one compartment of a device from another (such as
engine and exhaust manifolds). The following properties are important when
selecting materials for use in gaskets:
? flexibility;
? heat resistance;
? resistance to pressure;
? chemical resistance;
? low thermal conductivity;
? tear resistance; and
? resistance to crushing.
Asbestos is widely used for flange seals for pipelines and for gaskets in
compressors, turbine castings and motor vehicle. Gasket and jointing materials
that are considered as suitable substitutes for asbestos fall into a number of
categories depending on cost, material and application. Table 32 outlines the
properties of asbestos and some alternatives for use in gaskets ( Hodgson et al.,
1989). A more recent source for this type of information was not available.
Semi-metallic spiral wound gaskets and solid metal gaskets are another category
of articles in this area. These gaskets have specialised applications. Semi-
metallic gaskets consist of alternate layers of v-section metal strips and non-
metallic fillers. Solid metal gaskets are stamped out of sheet metal, or are
machined from cast or forged steel rings. These types of gaskets are used in
petrochemical and oil-producing industries and in nuclear power installations
where high temperatures and extremely high operating pressures prevail.
120 Priority Existing Chemical Number 9
Table 32 - Properties of asbestos and some alternatives for use in
gaskets
Chemical
Service Advantages Limitations
Material
resistance
temperature
(pH range)
(篊)
Asbestos/ 425 3-14 Better than asbestos
graphite in packings
Asbestos/ 250 3-14 Better than asbestos
PTFE in packings
Glass fibres 450 5-11 Good general- Limited chemical
purpose jointing resistance
Aramid 250 3-11 Strong fibre, long Difficult
fibres service life processing
characteristics
limited chemical
resistance
Graphite/ 250 1-14 Non-abrasive, good High price
PTFE heat dissipation,
excellent chemical
resistance, long
service life
PTFE 250 1-14 Low friction, excellent Thermal
chemical resistance expansion, low
shaft speed in
gland packings,
high price
Carbon 650 1-14 Good heat Brittle, not
dissipation, high shaft resistant to
speed in packings, oxidising agents,
excellent chemical high price
resistance
Graphite 650 (inert 1-14 Good heat Brittle, not
conditions dissipation, very high resistant to
eg. steam), shaft speed in gland oxidising agents,
3000 (non- packings, excellent high price
oxidising chemical resistance
conditions)
Vegetable 100 5-10 Inexpensive Limited
fibres, cork applications,
composites non-chemical
resistant, for low
pressure use
Source: Hodgson et al. (1989)
121
Chrysotile Asbestos
11.6.1 Use of alternative materials in gaskets in Australia
Investigations from industry surveys have shown that the use of non-asbestos
gaskets are increasing in proportion in Australia. The NICNAS vehicle
aftermarket survey found that only one company (Ford Australia) still use
asbestos head gaskets in new vehicles, and in only one model (Ford Econovan).
Richard Klinger is the only manufacturer of compressed fibre (CF) sheeting
(asbestos and non-asbestos) for gasket manufacture in Australia, although there
are at least two other manufacturers of gaskets plus a large number of processors
of gaskets from CF sheeting. Richard Klinger states that currently, 55% of `all
gaskets' and 70% of `compressed fibre gaskets' in Australia are non-asbestos and
that these proportions are increasing due to industry preference for non-asbestos
products.
Richard Klinger manufactures two major types of non-asbestos products:
compressed non-asbestos fibre jointing and non-asbestos spiral wound gaskets.
These non-asbestos products are used in a broad range of industrial applications
including sealing solutions for steam, oil, fuel gases, acids and alkalis.
Alternative materials used by Richard Klinger are graphite, carbon, glass, aramid
and ceramics. Technical advantages and disadvantages of these materials in
regard to use in gaskets are outlined in Table 33.
Asbestos seals tend to be better than non-asbestos due to the superior
performance of asbestos fibres in relation to temperature, pressure and chemical
compatibilities. However, Richard Klinger states that non-asbestos products can
be used in all applications where asbestos products are currently used, provided
that careful consideration is given to installation techniques and equipment
condition. For example, equipment which is of poor design or in poor condition
may not be suitable for direct replacement of asbestos with non-asbestos
products. Petroleum refineries were cited as an example, where such substitution
often requires upgrading of equipment. Many sealing products are used within
industry to contain volatile and/or toxic media and hence their reliability is
critical. In the experience of Richard Klinger, some high temperature, high
pressure type applications cannot be readily used with non-asbestos sealing
products without consideration of equipment redesign, which also carries a cost
consideration. However, Richard Klinger also reports that the proportion of
applications where changeover would be difficult is quite small compared to the
overall value of sealing products sold.
NICNAS investigations showed that there are alternatives in place in Australia
for gaskets, these are listed in Table 34.
122 Priority Existing Chemical Number 9
Table 33 - Advantages and disadvantages of alternative materials
used for gaskets according to Richard Klinger Pty Ltd.
Property Effect
Aramid Fibres
Advantages:
Will not melt: Stability through a wide temperature range (to 400篊)
Will not break down at elevated Gradual carbonisation into a carbon fibre skeleton
temperatures: preventing crushing under heat and pressure
Good chemical resistance: Suitable for the mixing and calendering process and
for a wide application range in the finished material
Disadvantages:
Not recommended for applications exceeding pH 11-
Limited resistance to caustic
12
solutions:
Breakdown of fibre causes gasket brittleness and
Hydrolysis if exposed to wet
subsequent failure
steam above 180篊:
Glass Fibres
Advantages:
Heat resistance: Can be used in high temperature applications without
fibre breakdown
Excellent chemical stability: Essential in the calendering process where some fibres
are prone to shrinkage.
Can be used in general purpose applications.
Resists hydrolysis: Ideal in medium pressure steam jointing materials
Disadvantages:
Limited resistance to higher Limits the ability to handle strong caustic flushes or
strength alkalis: strong caustic service applications (over pH 12)
Poor adhesion to binders in Low load capabilities without correct formulation for
virgin state: calendering process
Carbon Fibres
Advantages:
Enables use in higher temperature ranges approaching
Heat resistance:
that of asbestos fibres
Can be used for a wide range of chemicals and is to be
Chemical resistance:
used over the full pH scale (0-14)
Can be used in materials required to seal medium
Resists hydrolysis:
pressure steam
Disadvantages:
Cost: Initial outlay high, but offset by longer serviceability and
safer sealing
Lower adhesion to binders Without correct formulation with support fibres and
compared to compressed other ingredients, stress relaxation problems may arise
asbestos fibres (CAF):
123
Chrysotile Asbestos
Table 34 - Alternatives for gaskets in use in Australia
Use Alternative
Industrial:
Cylinder head gaskets paper (cellulose) gaskets
"
Exhaust manifold gaskets
graphite sheets
Gaskets for petrochemical and package boiler
industry
graphite and mineral fibre
Gaskets for sealing and rotating equipment
and associated equipment
ceramic fibre
Insulation for industrial machinery
nitrile/glass and graphite laminate
Pipeline/flanges for petroleum industry
Automotive:
carbon fibre, aramid,
Head, manifold and exhaust pipe gaskets
stainless steel, cellulose/glass fibre,
copper, aramid fibre, cellulose, rubber
coated steel, cellulose,
cellulose/aramid fibre
vegetable fibres
Insulator for automobiles
Outboard Engine:
aramid fibres
Cylinder head gaskets
"
Cylinder head cover gaskets
"
Exhaust plate gaskets
"
Exhaust manifold gaskets
"
Water pump gasket
124 Priority Existing Chemical Number 9
11.7 Health effects of alternative materials
Any substitution of chrysotile should be with a less hazardous substance. There
has been ongoing debate regarding the health effects of alternatives, such as
synthetic mineral fibres (SMF), natural organic fibres and synthetic organic
fibres.
In general, less data on health effects of alternative materials (in comparison to
asbestiform fibres) are available and because of this, it is difficult to make an
assessment of the pathogenicity and potential carcinogenicity of many substitutes.
Although not the only determinant of potential pathogenicity, fibre dimensions
(length, width and aspect ratio) are considered to be one of the most important
factors associated with carcinogenic (lung cancer and mesothelioma) potential
(EC, 1997). Table 35 presents data on fibre size for both asbestiform fibres and a
number of alternatives23. This table was compiled from a review of the literature
and the data may not be representative of all potential particle/fibre dimensions
for a particular material. The commonly accepted `peak hazard' dimensions, as
discussed in Section 7.3.5 of this report are >5祄 long (length) and <3祄 wide
(diameter).
The most commonly used alternatives in Australia (and overseas) for friction
materials are aramid fibres, attapulgite, fibreglass, refractory ceramic fibres
(RCF), semi-metallics, mineral wool, steel wool, cellulose, titanate fibres and
wollastonite, and for gaskets are glass fibre, carbon fibre and aramid fibre.
It is not within the scope of this report to assess the health effects of these
alternatives, however recent (peer reviewed) evaluations are presented for these
materials in Table 36, together with supporting reference material. It should also
be noted that, although Table 36 considers different fibres in distinct groups, it is
often misleading to do so, as differences in fibre length, diameter and surface
properties may lead to entirely different toxicological profiles.
A recent report by EC concludes that the available data are generally supportive
of the conclusion that PVA, cellulose, p-aramid, glass wool and slag wool are
likely to be safer in use than chrysotile. However, RCFs are the subject of
ongoing concern (EC, 1997).
A summary of a recent review (unreferenced summary report only available for
assessment ?full report not available for review) by the French Medical Research
Council (INSERM expert panel), made the following conclusions: that inhalation
studies in animals show a statistically significant increase in the number of
tumours with certain ceramic fibres, but not with either glass (excluding
continuous filaments) or rock wool fibres. However a non statistically significant
increase in tumour incidence was found in animals exposed to fibre glass. No
conclusions could be drawn for slag wool, continuous glass fibres, para-aramid or
cellulose fibres due to lack of data. Radiological studies in workers did not yield
any firm conclusions about a relationship between exposure to glass, rock or slag
wool or woolastonite and benign pleural lesions or pulmonary fibrosis. However
there is a possible relationship between exposure to refractory ceramic fibres and
pleural plaques. No information is available for assessing the risks of pleural or
23
Not all the listed non-asbestos fibres are used in friction products or gaskets.
125
Chrysotile Asbestos
parenchymatous lesions associated with exposure to continuous glass fibres, para-
aramid or cellulose fibres in humans (INSERM, 1998).
Table 35 ?Dimensions of asbestos fibres and alternative (non-
asbestiform) materials
Fibre type Fibre length Fibre diameter DF50(祄)
(祄) (祄)
Asbestiform Fibres:
5 - 302 0.05 - 0.52
Amosite 0.15
5 - 302 0.05 - 22 0.52
Anthophyllite
0.44* - >0.513 0.035 - 0.072
Chrysotile 0.25
5 - 302 0.052 - 0.47
Crocidolite 0.17
Erionite (Zeolite) NA NA 0.005
Tremolite NA NA NA
Alternatives:
1 - 101 2 - 31
Alumina fibre (refractory) NA
**2.5 - 3012 <1 - 2012 1 - 2.512
Aramid(Kevlar/Twaron)
Attapulgite (palygorskite) NA NA NA
20 - 609 5 -151
Carbon (graphite) fibre NA
>514 12-4013
Cellulose fibres NA
2 2
Ceramic fibre (RCF) 2 - 500 0.2 - 6 1.5
Silicon carbide
18.1 - 197 0.8 - 1.57 NA
whiskers
1 - 2 14 3 - 3014 NA
fibres
Ceramic fibres (other):
1 - 201
Cera blanket NA NA
0.75 - 101
Cera felt NA NA
0.75 - 201
Cera fibre (bulk) NA NA
1
NA
Cera form NA 2 - 10
1
Cera paper NA 1-6 NA
30510 0.5 - 151
Fibrefrax NA
0.3 - 201
Kaolin wool NA NA
0.2 - 251
Kerlane NA NA
0.3 - 181
Zirlane NA NA
Dawsonite NA NA NA
11
0.3 - 181 8.2511
Glass fibres: **45.2
5
10 - 151
E-glass 3-6 NA
10 - 201
Textile NA NA
200 - 8005 45
Mineral Wools: NA
1 - 251 0.3 - 201
Glass Wool (fibreglass) 0.38 - 3.5
0.3 - 101
Rock Wool/Stone Wool <5 - 22 NA
6
4.8
Slag Wool <5 - 22 2-6
**22711 10 - 2012 31.611
Polyacrylonitrile (PAN)
**25411 10 - 2012 34.411
Polypropylene
>513 9.3 - 16.58
Polyvinyl alcohol (PVA) NA
8 - 101
Silicate fibre NA NA
Steel Wool NA NA NA
5
0.2 - 0.55 NA
Titanate fibre 10 - 20
1 5
1 - 5001 1.2 - 1.311
Wollastonite 5 - 25
1 2 3 4
Data sources: NIOH (1994) ; Rogers and Fornasari (1988) ; Stanton et al (1981) ; Plato, (1995) ;
5 6 7 8 9
Anderson (1996) ; CEPA ; Vaughan et al (1993) ; EC (1997) ; Owen et al (1986) ; unpublished
10 11 12 13; 14
source (various) ; Cambelova & Juck (1994) ; ECETOC (1996) ; UK HSE (1998) Lockey (1996)
* majority of chrysotile fibres in the debris from friction linings measured in automotive workshops
were less than this figure.
**geometric mean.
DF50 = 50% abundance diameter of fibres (from Spurney (1995), unless otherwise referenced.
NA = not available for assessment.
126 Priority Existing Chemical Number 9
127
Chrysotile Asbestos
128 Priority Existing Chemical Number 9
129
Chrysotile Asbestos
130 Priority Existing Chemical Number 9
12. Secondary Notification
Under Section 65 of the Act, the secondary notification of chrysotile may be
required where an applicant or other introducer (importer) of chrysotile and/or
chrysotile-containing products, becomes aware of any circumstances which may
warrant a reassessment of its hazards and risks. Specific circumstances include:
a) the application/function of chrysotile or chrysotile-containing products has
changed or is likely to change. In this regard, notice should be paid to section
14.2.(c) of this report;
b) the usage and/or the amount of chrysotile or chrysotile-containing products
introduced into Australia has increased or is likely to increase, significantly;
c) the conditions of use are varied, in such a way that greater exposure (to workers
or general public) to chrysotile fibres may occur; and
d) additional information has become available to the applicant/notifier as to the
adverse health and/or environmental effects of chrysotile.
The Director must be notified within 28 days of the applicant/notifier becoming
aware of any of the above circumstances.
131
Chrysotile Asbestos
13. Discussion and Conclusions
13.1 Scope of the assessment
This report has focused on: the occupational, public health and environmental
risks associated with current uses and applications of chrysotile in Australia.
In particular, the assessment has focused on the importation of chrysotile for
manufacture of friction products and gaskets together with the use of these
products in a variety of `down stream' industrial/occupational sectors. Also
assessed was the use of chrysotile as an additive in a specialty epoxy resin
adhesive.
Assessment information was obtained from a number of sources. Information on
imports/exports of raw asbestos/chrysotile and products were obtained from
Australian Customs Service (ACS) and Australian Bureau of Statistics (ABS).
Data (including exposure monitoring, production process details, risk
management strategies and copies of labels and MSDS) were provided by
Applicants (i.e., manufacturers of chrysotile products) and end users (in particular
the Automotive and Aircraft industries). Much of the information on end use of
friction products and gaskets and substitute (alternative) products was obtained
from a NICNAS `Automotive Aftermarket Survey' which incorporated an
exposure monitoring study carried out by NOHSC. Information on Australian
and overseas regulation/legislation was obtained through a NICNAS
commissioned consultancy, which included an evaluation of mechanisms for
restricting uses and importation of chrysotile-containing products.
13.2 Current use in Australia
Over the past 15-20 years, asbestos consumption worldwide has generally
declined, especially in the US and European markets.
In Australia, the mining of asbestos (all forms) ceased in 1983. Asbestos (all
forms) has not been exported from Australia since 1984. Chrysotile is the only
form of raw asbestos being imported into Australia (by 3 companies) and has
remained at approximately 1-2 thousand tonnes per year over the past decade,
Canada being the sole source of these imports. Despite the increased importation
of non-asbestos products over the past few years, imports of asbestos (assumed to
be mainly chrysotile) products, particularly friction products and gaskets, do not
appear (see section 5.2.3 for qualification) to be declining.
Asbestos is still present in the general Australian community from a range of past
uses, which have been carried out for substantial periods of time. However,
assessment of exposure from past uses was considered outside the scope of this
PEC Report as they are adequately dealt with by local government authorities and
under existing regulation and controls. Examples of some of these past uses are
provided in Section 5 of this report.
132 Priority Existing Chemical Number 9
In Australia imports of raw chrysotile are used mainly in the manufacture of
friction materials and CAF sheeting for gasket production with a small quantity
being used in the manufacture of a `non-sag' additive in an epoxy resin adhesive.
All these uses, according to manufacturers, are being phased out.
Brake linings and gaskets were found to be the main asbestos products imported
for use in Australia. Most clutch facings (approximately 99%) for both
automotive and industrial applications are now asbestos free. Chrysotile brake
linings are imported for industrial applications and use in passenger motor
vehicles, although most linings imported for these applications are non-asbestos.
The use of brake blocks in Australia is declining; the predominant use of which
was found to be for industrial applications (e.g. railway industry and mining
equipment). A significant percentage of these brake blocks are non-asbestos.
Customs data do not permit differentiation between asbestos and non-asbestos
gaskets. Investigations indicated that a significant number of non-asbestos
gaskets are being used for industrial applications, however there continues to be
large numbers of asbestos gaskets still used.
A small number of `one-off' uses for asbestos products were also identified.
These products include blades in high vacuum pumps, asbestos yarn in packing,
asbestos gloves and asbestos washers for oil flame safety lamps (used by miners).
Investigations indicate that importation of asbestos fibre cement products is very
unlikely.
In the new vehicle importing and manufacturing industries only one company
reported the use of asbestos `original' equipment (in two of their current models).
The remaining companies surveyed, used non-asbestos original equipment. The
majority of these companies reported that they have policies in place regarding
not using asbestos products.
The majority of industrial equipment and machinery, such as agricultural
machinery, have non-asbestos original equipment. A significant number of these
companies use non-asbestos parts in both superseded and new equipment and
machinery. Most of these companies stopped using asbestos parts in the late
1980s.
In the aircraft industry, asbestos parts are still being used in new and older aircraft
(e.g., gaskets and seals). However, in this industry there is a continued effort
towards the identification of possible substitutes.
13.3 Effects of concern
Chrysotile is a known human carcinogen and has been classified as such by
NOHSC. As with other forms of asbestos, chrysotile can cause asbestosis, lung
cancer and mesothelioma in humans and animals in a dose related manner. The
Australia Mesothelioma Program reports that Australia has the highest incidence
of mesothelioma in the world (Leigh et al., 1997).
Controversy exists over the potency of chrysotile in relation to other forms of
asbestos (crocidolite, amosite and tremolite) and whether asbestosis is a
prerequisite for cancer and hence, whether a level of exposure for chrysotile
exists, below which there would be no risk to human health (i.e., an exposure
threshold for carcinogenic effects). As such, linear extrapolation methodology
has been used to provide a conservative estimate of risk.
133
Chrysotile Asbestos
Risk estimates for lung cancer in workers appear to be dependent on both
cumulative exposure and the type of industry where exposure has occurred.
NOHSC (NOHSC, 1995a) has estimated the lifetime risk of lung cancer, based
on the best available epidemiological data (from friction products industries
overseas) as up to 173 additional cancers per 100,000 workers exposed to a daily
average of 1 chrysotile fibre per mL. Extrapolation for lower exposures provides
lifetime risk estimates (per 100,000 population) of 86 and 17 for exposure to 0.5
and 0.1 f/mL, respectively, although estimates by US NIOSH and OSHA are
between 4 and 30 times higher (Lash, 1997; Stayner et al 1997). There are many
confounding factors surrounding risk estimates for chrysotile exposure, the most
important of which are; the possibility of a threshold effect, possible co-exposure
to other fibre types, inaccurate estimates of historical exposures and the influence
of tobacco smoking.
Conclusions by scientific experts in a recent consensus report (see section 10.2.1)
were: that all asbestos fibres can cause mesothelioma, but amphiboles are more
potent carcinogens for the mesothelium; that low level exposure to asbestos is
sufficient to cause mesothelioma; that cumulative exposure to 25 fibre-years
(fibre.year/mL) is sufficient to cause lung cancer and that asbestosis is not a
necessary prerequisite for lung cancer.
13.4 Exposures arising from current use
13.4.1 Occupational
Exposures of most concern are those where friable chrysotile may be generated.
Occupational exposure may arise from the manufacture of CAF sheeting and
other products (mainly friction products) and during processing and end-use
(replacement) of these products, where public exposure may also occur. The
major route of exposure is inhalation.
Air monitoring data were provided by two producers of chrysotile products,
Bendix Mintex and Richard Klinger. Data for the period 1992 to 1997 (for
Bendix Mintex), indicated that more than 80% of personal samples were less than
0.1 f/mL. Only 2 samples during this period exceeded 0.5 f/mL. Monitoring data
(1991-96) at Richard Klinger (Perth site, where raw chrysotile is handled),
indicated that approximately 60% of the personal air samples were less than 0.1
f/mL, with only one sample exceeding 0.5 f/mL. Personal and static samples for
the years 1989, 1991, 1993 and 1995 at Richard Klinger (Melbourne site, where
production of gaskets takes place) were all less than 0.05 f/mL (static exposures
below 0.01 f/mL). Air monitoring data from other sources were also assessed,
which included an automotive aftermarket survey of service garages in Western
Australia where exposure levels were found to be less than 0.1 f/mL.
Vivacity Engineering, who manufacture an epoxy resin adhesive containing
chrysotile, has not conducted air monitoring during manufacturing processes.
However, once in place, the hardened adhesive is not considered to be of concern.
134 Priority Existing Chemical Number 9
The NICNAS Automotive Aftermarket Survey showed that exposure to friable
asbestos is highest in the brake bonding industry during grinding of brake shoes
and cutting of brake linings. The highest personal monitoring result obtained
was 0.16 f/mL, during machining of brake shoes. Work in the brake bonding
industry is declining due to the availability of brake pad and clutch kits
(preformed to standard sizes) which do not require modification before
installation. However it was reported that 90% of current activities in this
industry sector involve asbestos-containing material.
International monitoring results in service garages indicated exposure levels were
generally below 0.2 f/mL. Data for personal and static short-term sampling in
workshops involved in the removal (wet) and replacement of asbestos gaskets
were <0.05 and <0.03 f/mL respectively. However, higher exposure levels were
noted during the `dry' removal of gaskets (up to 1.4 f/mL).
Both national and international data indicate that present exposure levels are
lower than in the past. Reduced exposure levels could be due to increased
awareness of the hazardous effects of chrysotile among workers and/or due to
implementation of regulatory controls and better work practices (e.g. prohibition
of use of compressed air to blow asbestos dust and diminished use of grinders)
during brake and clutch servicing.
Monitoring results also indicate that over the past decade, the majority of
exposures were below the current NOHSC national exposure standard (1 f/mL)
for chrysotile (this standard is under review - see section 13.5). However, it
should be noted that this standard relates to exposures where chrysotile is the only
asbestos fibre present. Where other forms of asbestos (e.g., amosite or
crocidolite) are present or where the composition is unknown, the NOHSC TWA
exposure standard is 0.1 f/mL (NOHSC, 1995d).
13.4.2 Public
The major source of public exposure is from chrysotile dusts generated by vehicle
braking, although the level of exposure is very low. Overseas and Australian
studies showed very low air levels of chrysotile fibres at busy intersections (less
than 0.01 f/mL) or freeway exits (0.5 particles/mL), generated by braking
vehicles. At a location of 30 metres from the nearest traffic, air levels were
below the limit of detection. There are no data on exposure of home mechanics
during the changing of brake pads and shoes. However, the time-weighted
exposure of home mechanics is unlikely to be higher than that of workers in
automotive brake service centres.
13.4.3 Environment
When chrysotile is encapsulated in end use products such as brake linings and
epoxy-resin adhesives, it is unlikely that fibres will be in a form where an
environmental hazard is posed. Based on available data for Australia, it can be
predicted that the manner of use of chrysotile (including release from driving and
wastes from manufacturing) as outlined in this report, will result in a low
exposure and hazard to the environment.
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Chrysotile Asbestos
13.5 Current regulation and risk management
13.5.1 Australia
In Australia, legislation is currently in place that restricts or controls activities
involving use of asbestos. Chrysotile is regulated (usually under the definition of
asbestos) through various State/Territory regulations relating to dangerous goods
(transport), OHS and the environment. In addition, local governments have
specific requirements for building and construction work involving asbestos.
Current prohibitions on use/importation of asbestos and products relate solely to
other asbestos types (mainly amphiboles), and in some cases specifically exclude
chrysotile. In addition, the extent to which asbestos products (articles) are
regulated under current legislation is often unclear due to differences in
definitions (e.g., asbestos material, and asbestos process).
Chrysotile is regulated in the workplace under hazardous substances legislation
enacted by the Commonwealth, States and Territories. This is based on the
NOHSC Hazardous Substances Model Regulations, which address
issues/requirements such as control measures, labeling, MSDS, exposure
standards, classification and scheduling and health surveillance.
The NOHSC national exposure standard for chrysotile is 1 f/mL, however the
States and Territories have not uniformly adopted this. In March 1993, NOHSC
noted information in a report on the levels of lung cancer risk presented by
chrysotile and its application to various industries. Since this time the national
exposure standard for chrysotile has been under review24 (with public comment
sought on proposed standards of 1 f/mL, 0. 5 f/mL and 0.1 f/mL).
From the exposure data gathered, it can be concluded that OHS control measures
are available to control exposure to below current national and State/Territory
exposure standards. In the majority of workplaces studied, measured exposures
were at or below 0.1 f/mL25.
Deficiencies were noted in MSDS and labels (for both raw chrysotile and
products) with regard to NOHSC requirements, particularly in regard to labeling
of imported products, where in some cases labels did not state that the product
contained asbestos material. Induction training and health surveillance were also
considered inadequate in some workplaces. With respect to health surveillance,
new developments in diagnostic methods, as highlighted in the Helsinki criteria
(Anon, 1997), need to be considered by NOHSC with respect to their current
requirements (NOHSC, 1995c).
Other relevant NOHSC risk management activities include discussions with
NHMRC in relation to prevention and treatment of asbestos-related diseases and
the development of a strategy (in consultation with State/Territory jurisdictions)
for dealing with asbestos-related diseases, which will include further research
requirements (Labour Ministers Council, 1998).
24
The NOHSC Hazardous Substances Sub Committee has agreed that this PEC report will
supplement public comments in the review of the exposure standard for chrysotile.
25
It should be noted that where exposure to other asbestos fibres is possible, the NOHSC exposure
standard is 0.1 f/mL (NOHSC, 1995d).
136 Priority Existing Chemical Number 9
With regard to road safety, regulations/standards are in place in a number of
States and Territories (made under the Road Safety Act, 1986 and the Motor
Vehicle Standards Act 1989) relating to the quality/testing of friction products.
Examples are the Australian Design Rules, developed by the Federal Office of
Road Safety (FORS) and the Australian Standard for the Evaluation of
Aftermarket Disc Pads for Passenger Vehicles (Standards Australia, 1997).
13.5.2 Overseas
A number of initiatives have been undertaken at the international level to regulate
asbestos use and exposure, the most notable of which are the EU Directives on
the marketing and use of asbestos, which contain specific prohibitions on the use
of certain chrysotile products and certain work practices. Other initiatives
include the ILO Convention 162 and the Helsinki criteria that aim at providing a
framework for policies to protect worker health and for recognition, attribution
and screening for asbestos related diseases.
The majority of countries regulate use of asbestos and asbestos containing
products. Current regulation/legislation was assessed from 13 countries. As with
Australia, none of these countries have implemented absolute bans on chrysotile
or chrysotile products, as relevant legislation in most countries contains either
specific exemptions for certain classes/types of products or general exemptions
whereby government authorities may grant exemptions on application.
In most countries assessed, vehicle manufacturers are using asbestos-free parts
for new vehicles and use in older vehicles is subject to phase-out regulations.
Chrysotile products are the most common exemptions in the regulations (on
asbestos) assessed and friction products and gaskets are the most common class
of product exempted. Most exemptions for these products are either for a
prescribed period of time and/or are subject to the development/availability of
suitable (i.e., safe performance and lower health hazard) alternative products for
specific applications.
13.6 Alternatives
NICNAS surveys on the use of asbestos alternatives indicated that substitution is
occurring in many industries and at a quickening pace. In Australia, chrysotile
has been replaced for many uses, including railway blocks, cement sheeting,
tubes and piping, roofing tiles, and fibre insulation/packing.
The NICNAS Aftermarket Survey found that the automotive industry is moving
rapidly towards using non-asbestos products (friction products and gaskets) with
almost all new vehicles now asbestos free. Replacement non-asbestos parts are
reported to perform as efficiently or better than asbestos parts (Baker, 1992).
However, Bendix Mintex has advised that their testing results indicate that a
number of sub-standard alternative products are being introduced to the
Australian market, mainly from non-Japanese Asian sources. Non-asbestos parts
are also available for some superseded models and clutches. With respect to
older vehicles fitted with `asbestos original' equipment, the suitability and
efficacy of using non-asbestos replacement parts was difficult to ascertain, due
mainly to the fact that the testing of non-asbestos parts in most old vehicles is
reportedly costly and hence limited. However, other countries would also have
137
Chrysotile Asbestos
faced this issue during phase-out of chrysotile friction products, which should
expedite the development of suitable alternatives.
Bendix Mintex indicate that they have a product range of non-asbestos brake
linings which covers around 90 per cent of vehicle models in Australia, however
the extent of coverage for the remaining market by other suppliers of alternative
friction products was not ascertained. In order to evaluate current and future use
of asbestos products in the aftermarket, an assessment of the age of vehicles in
use in Australia compared to other countries was carried out. In a recently
available survey it was found that Australia has the highest percentage of cars
older than 10 years, which may account for the sustained importation and use of
chrysotile products in the automotive industry. Other explanations for continued
use (of asbestos products) are the cost differential between asbestos and non-
asbestos products and the fact that there are no regulations aimed at preventing
replacement of non-asbestos with asbestos parts in the aftermarket. Bendix
Mintex also reports that preferences exist for asbestos products based on `driver
perception' of performance.
Investigations also revealed that in some industries, asbestos gaskets are still
used, reportedly because no alternatives currently meet the use requirements. For
example it is reported that no substitutes have been developed to withstand high
temperature and high-pressure conditions for gasket use in the petrochemical
industry. Therefore there is also a need for further research into substitutes for
asbestos gaskets.
A considerable amount of information on alternatives was reviewed in this
assessment. The International Programme on Chemical Safety (IPCS) and the
European Union have also conducted reviews of alternative fibres. The reports of
these bodies provide significant data on the safety of alternatives. There are
alternatives that are considered to be safer than chrysotile. However there is a
potential that alternative fibres which have similar physical properties
(particularly fibre dimension) to chrysotile may exhibit similar toxicological
profiles. Therefore further work is required to generate health effects data for
proposed alternative materials.
Replacement of chrysotile with other substitute materials must take into
consideration all available toxicological, physicochemical and performance data
to ensure that the selected substitutes are likely to present lower health risks than
chrysotile for each particular use, without compromising road safety.
138 Priority Existing Chemical Number 9
14. Recommendations
14.1 Preamble
This section provides the recommendations arising from the PEC assessment of
chrysotile. Recommendations are directed at regulatory and non-regulatory
bodies and users of chrysotile products. In order to facilitate consideration of
these recommendations, the following provides a summary of the critical issues
to be weighed. These should form the basis of a balanced action plan.
? Chrysotile is a known human carcinogen.
? Prudent OHS policy and public health policy favors the elimination of
chrysotile wherever possible and practicable.
? The main exposure to Australian workers arises from manufacture,
processing and removal of friction products and gaskets. Home mechanics
are also exposed during `do-it-yourself' replacement of brake pads/shoes.
Due to the friability of these products in certain applications, these exposures
are of concern.
? While the majority of current workplace exposures are below the current
national exposure standard for chrysotile of 1 f/mL26, this standard is
currently under review by NOHSC. This exposure standard applies to all
chrysotile exposures, both from the uses within the scope of this assessment
and arising from chrysotile in situ from past uses.
? While the level of the exposure standard, once revised, will apply to all uses
and exposures, the fact that a standard exists to deal with exposures from past
uses should not be seen as limiting the ability to eliminate exposures arising
from current uses.
? Current overseas experience with the phasing out of chrysotile products
indicates that a range of alternatives is available to suit the majority of uses.
Good OHS practice dictates that use of chrysotile products should be
restricted to those uses where suitable substitutes are not available, and
alternatives should continue to be sought for remaining uses.
? Despite the introduction of non-asbestos parts for the new vehicle fleet,
current import data indicate that the import of chrysotile products (mainly
friction products and gaskets) is not decreasing.
? A phase-out of chrysotile would require an organised and collaborative
approach between industry and government. This would need to take into
account manufacture, import, processing, export and distribution in
commerce of all chrysotile products. Consistent with experience in Australia
and overseas, a `staged' approach would be required, enabling limited
exemptions where suitable alternatives are genuinely not yet available, and
taking into account health and road safety issues. In general, the use of time
26
It should be noted that where exposure to other asbestos fibres is possible, the NOHSC exposure
standard is 0.1 f/mL (NOHSC 1995d).
139
Chrysotile Asbestos
frames for phase-out provide an essential incentive towards development of
alternatives.
? Worker exposure may also arise from removal of friction and gasket products
fitted by members of the general public (e.g., during home car maintenance).
Compliance difficulties would be expected if use sectors were not treated
similarly with respect to access to chrysotile products. A phase-out of
chrysotile would need to encompass both workplace and public use.
? Best practice must be implemented to minimise occupational and public
exposure, and to minimise environmental impact, over the remaining
period(s) of use.
? A risk reduction strategy using all available and appropriate measures is
required to ensure that the risks posed by chrysotile are continually reduced
and eliminated wherever possible.
14.2 Recommendations
Recommendation 1: Phase-out (importation and local manufacture)
It is recommended that the uses of chrysotile in Australia, including manufacture
for the purpose of export, be phased out over time, with the period of phase out to
be determined by the relevant regulatory authorities.
In achieving this it is further recommended that:
a) Specific phase-out periods should be set, with stages (over the shortest
possible period of time) to encourage and reflect the availability and
suitability of alternatives.
b) Action is taken in the immediate future to prohibit the replacement of worn
non-chrysotile original equipment with chrysotile products, as alternatives are
now available.
c) No new uses of chrysotile or chrysotile products should be introduced (i.e.,
an immediate prohibition on new uses).
d) Occupational health and safety authorities take the lead role in considering
this recommendation and specific strategies to implement it as worker health
is identified as the major concern. This role would require involvement of
other relevant authorities, including road safety authorities.
e) That NOSHC consider use of the existing hazardous substances control
framework in order to avoid adding to the numerous existing pieces of
regulation for asbestos. This would enable controls over both supply and
workplace use. It would also enable any necessary Regulatory Impact
Statement (including road safety issues) to be undertaken. This mechanism
would need to be supplemented by controls over supply for public use by the
relevant authorities.
To facilitate any phase out it is further recommended that:
f) Substitution of chrysotile by less hazardous materials is facilitated by
dissemination of information to industry, workers and the public about
suitable alternatives for specific uses. In particular, it is recommended that
140 Priority Existing Chemical Number 9
data on performance testing be obtained by importers/distributors of
alternative friction products prior to release of any new products into the
Australian marketplace. In this respect, industry bodies can make a
significant contribution to the recommended phase-out.
g) The assistance of the Australian Customs Service and Australian Bureau of
Statistics is sought to identify necessary changes required for compliance as
currently, there are shortcomings in the customs coding of imported
chrysotile products. This would include improvements to enable distinction
between asbestos and non-asbestos materials, for all categories of products
and to reduce the possibility of misclassification. Consideration should also
be given to using similar tariff classifications/codes for exports and imports.
h) Activities are initiated to promote maximal use of non-asbestos friction
materials where these have been specifically identified as substitutes. To
facilitate this, guidance information should be made available for chrysotile
original equipment vehicles (as with new vehicles) which should include
details of suitable non-asbestos friction materials. Participation of the
manufacturing and aftermarket industry, insurance companies and motoring
organisations in such activities would lead to a more extensive penetration of
the aftermarket.
Recommendation 2: NOHSC Hazardous Substances Framework
It is recommended that a number of areas of the NOHSC Hazardous Substances
Framework, which includes the Model Regulations for the Control of Workplace
Hazardous Substances, be considered for review and update, as follows:
a) Classification. Prior to publication of this report the EU updated its
classification for chrysotile, replacing R45 (may cause cancer) by R49 (may
cause cancer by inhalation). This revised classification is supported and its
inclusion in the NOHSC List of Designated Hazardous Substances will need
to be adopted by NOHSC according to the usual process.
b) Exposure standards. It is recommended that NOHSC consider this report in
the context of its current review of the exposure standard for chrysotile. In
particular noting, (i) for health hazards, that there is considered to be no safe
level of exposure to chrysotile, and (ii) the exposure data collected for this
report from Australian workplaces.
Priority consideration should also be given to the development of standards
for asbestos alternative materials that do not have a national exposure
standard, and maintenance of exposure standards where they already exist. In
particular, for alternative fibres that are currently being used in friction
products and gaskets.
c) Methodology for fibre analysis. In conjunction with consideration of the
exposure standard, noting that the analytical methods differ in their level of
detection of chrysotile, it is recommended that the adequacy of the current
standard method of analysis should be considered. This may be required to
support any change in the exposure standards for chrysotile and/or alternative
fibres.
141
Chrysotile Asbestos
d) Health surveillance guidelines. It is recommended that NOHSC review
these guidelines to ensure they are up to date with current knowledge on
detection of chrysotile-related health effects in workers.
e) Carcinogen regulations. Consideration of any phase-out recommendation
(see Recommendation 1) will require update and review of the current
scheduling of chrysotile in Schedule 2 to the Model Carcinogenic Substances
Regulations.
Recommendation 3: Implementation of Workplace controls
It is recommended that manufacturers, suppliers and users comply with the
requirements of the NOHSC Hazardous Substance Model Regulations, as
adopted by States/Territories, in particular:
a) Classification. The review confirms the current classification of chrysotile as
a carcinogen category 1 (R45), with danger of serious damage to health from
prolonged exposure (R48), as listed in the NOHSC List of Designated
Hazardous Substances. However note the foreshadowed change in
Recommendation 2a) above.
b) MSDS. Noting major inadequacies in some existing MSDS, MSDS should
be updated and reviewed to comply with requirements. This should include
ensuring that adequate information is provided on ingredients, health hazards,
the Australian exposure standard, personal protective equipment, safe
handling and disposal and contact details for further information. Where
MSDS are not provided for chrysotile products, sufficient information on
hazards, safe handling and precautions for use must be present on the label
and/or supplementary information (e.g. information sheets) present in the
product packaging. The latter approach would also ensure adequate
information for use by the general public, where MSDS would not be
required by legislation.
c) Labeling. Noting the inadequacies of labeling identified in this assessment,
labels should be reviewed and updated to ensure they comply with
requirements. In accordance with the Model Regulations, this is a duty of the
manufacturers and importers. In the workplace, if it is not clear whether a
product is asbestos or non-asbestos, procedures must be in place to ensure
that the product is handled as if it were asbestos and labeling solutions should
be sought to assist identification of types of hazardous fibres present. This is
particularly relevant for the aftermarket industry, due to the need to remove
and dispose of worn parts and in some cases to further process replacement
parts (e.g. brake bonding).
d) Exposure monitoring. Should be continued to enable exposure to be reduced
to the minimum feasible level and in accordance with the relevant exposure
standard. This includes those applications of asbestos/chrysotile identified in
this report where little if any exposure monitoring data were available. In
conjunction with review of the NOHSC national exposure standard for
chrysotile, it is recommended that relevant State/Territory and other
Commonwealth regulatory authorities provide advice on the work situations
were exposure monitoring is indicated. This will be dependent on the
142 Priority Existing Chemical Number 9
standard set, and should also take into account the representative exposure
data provided in this report.
In addition, applications where workers are potentially exposed to alternative
`non-asbestos' fibres should also be monitored, with regard to compliance
with exposure standards (NOHSC 1995d).
e) Engineering controls and safe work practices. It is recommended that the
current controls and practices in workplaces be reviewed and updated, in
order to eliminate, wherever possible, exposure in the workplace.
f) Health surveillance. It is recommended that health surveillance be carried
out in accordance with the NOHSC Health Surveillance Guidelines for
`chrysotile'.
g) Training. It is recommended that those employees who are potentially
exposed to chrysotile are provided with an adequate induction and training
program, which should incorporate:
? safe work practices and procedures to be followed, including correct use
and maintenance of control measures, disposal of asbestos containing
waste and cleaning of overalls/clothing;
? proper use and fitting of personal protective equipment;
? provision of MSDS and explanation of information contained in MSDS
and labels; and
? nature of health surveillance required.
Recommendation 4: Public health and safe disposal
a) Continued progress towards a phase-out of chrysotile in favour of less
hazardous materials is supported. This phase out should be conducted with
care so that greater risks to road safety are not introduced through inferior
performance of substitute materials.
b) It is recommended that a warning be carried on the label/packaging of brake
pads/shoes containing asbestos/chrysotile that are available to the public for
`do it yourself' repair and maintenance. A suggested wording is as follows:
Warning - this product contains asbestos. When exchanging brake
pads/shoes, do not inhale brake-housing dusts. Do not blow or use
compressed air to remove dusts from the housing, as repeated exposure
to the dust may cause lung disease, including cancer.
c) Risk management options need to address disposal of used chrysotile
containing products (e.g., provision of re-sealable bag - for disposal of old
parts - could be enclosed with asbestos friction products available to
consumers).
Recommendation 5: Environmental disposal measures
a) Disposal of used asbestos parts to standard municipal landfills is acceptable.
However it is recommended that all workplace asbestos waste be collected
and disposed of by licensed hazardous waste contractors.
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Chrysotile Asbestos
b) It is recommended that handling of chrysotile waste and disposal of used
chrysotile packaging is in accordance with the following:
For friable asbestos/chrysotile collected under dust extraction techniques:
Waste collected under dust extraction methods should be put in properly
labeled translucent bags (polyethylene) with a minimum thickness of 100
microns. Bags should be sealed immediately after filling, and stored in an
area where they cannot be broken or otherwise disturbed. They should be
collected and disposed of by a licensed hazardous waste contractor.
For waste bags of imported raw chrysotile:
Sacks or bags which contain loose asbestos fibres, or mixtures including
loose asbestos fibres, should be deposited in a suitable receptacle, under a
dust extraction hood immediately after being emptied. Where possible, the
bags should be shredded and recycled in the process.
For disposal, bags should be sealed in an impermeable outer bag and
deposited in an appropriate landfill. A further method of plastic bag disposal
is melting. By melting the empty bags and wrappers, the asbestos residue
becomes embedded in the melted plastic. Under no circumstance should bags
be reused for packing or other purposes.
Recommendation 6: Public Information
It is recommended that appropriate measures are taken to disseminate information
in order to provide information to the community with regard to issues addressed
in Recommendations 1b, 3, 4 and 5. Suggestions on this issue in the public
comment phase for the draft PEC report were that such measures could be
addressed in a campaign facilitated by participation of unions, industry, motoring
associations and health authorities. The type of activity required will be
dependent on the risk management action to be implemented.
Recommendation 7: Secondary notification
The National Industrial Chemical (Notification and Assessment) Act 1989
prescribes circumstances where secondary notification is required. Examples are
provided in Section 12 of this report.
Recommendation 8: Data gaps and further studies/research
requirements
In general, the following research is strongly supported:
a) It is recommended that research into alternatives to chrysotile should actively
continue, taking into account the need to ensure that the relevant hazard
information is generated to ensure that proposed alternatives present reduced
risks to health and the environment.
b) At present it is not possible to identify a level of chrysotile exposure below
which there would be no risk to human health. Further information on this,
including full elucidation of the mechanism of action for chrysotile induced
lung disease and mesothelioma, would assist regulatory decision-making.
144 Priority Existing Chemical Number 9
APPENDIX 1
LIST OF APPLICANTS
Bendix Mintex Pty Ltd
Elizabeth Street
Ballarat
Vic 3353
Richard Klinger Pty Ltd
138-146 Browns Road
Noble Park
Melbourne
Vic 3174
Vivacity Engineering Pty Ltd
3 Sefton Road
Thornleigh
NSW 2120
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Chrysotile Asbestos
APPENDIX 2
SOURCES OF INFORMATION
Information/data submitted by the applicants
? Quantities of `raw' chrysotile imported into Australia;
? Uses of chrysotile by the applicant;
? Description of the persons to whom the applicant has supplied or intends to
supply chrysotile and chrysotile products;
? Methods used or proposed to be used by the applicant in handling chrysotile and
chrysotile products;
? Occupational exposure data;
? Occupational health monitoring ?atmospheric monitoring and health surveillance
? Information on prevention of exposure to chrysotile;
? Release of chrysotile to environment;
? Transportation and storage;
? Disposal;
? Hazard communication ?MSDS, labels etc.;
? Alternatives (substitutes) for chrysotile/asbestos, their composition and efficacy;
and
? Reference papers from overseas sources relating to health effects of chrysotile, air
monitoring, information on alternatives and the use of chrysotile products in the
aftermarket.
Other sources of information
Other sources of information included:
? CD-ROM database searches;
? Australian regulatory agencies and institutions, including NOHSC, FORS, FCAI,
ABS, ACS, AAA and Monash University;
? Overseas regulatory agencies, including UK Health and Safety Executive,
USEPA, Ministry of Social Affairs and Health in Finland, National Institute of
Health and Medical Research in France, Swedish National Chemicals
Inspectorate; and
? Institutions such as The Asbestos Institute and the Asbestos International
Association.
146 Priority Existing Chemical Number 9
Australian Bureau of Statistics (ABS) and Australian Customs Services
(ACS) data
Information on quantities of asbestos and asbestos products (import and export) was
retrieved from the Australian Bureau of Statistics (ABS) and Australian Customs Service
(ACS).
There are four major customs tariff categories, including subcategories, relating to the
import of asbestos and asbestos products. The customs categories, product types and
quantities imported in 1997 are provided in Appendix 3, figures 1A-1D. These four
categories are:
? 2524 - Asbestos
category includes chrysotile (white asbestos) and other asbestos types (Appendix
3, Fig. 1A);
? 6811 - Articles of asbestos-cement, of cellulose fibre-cement or the like
may or may not contain asbestos (Appendix 3, Fig. 1B);
? 6812 - Asbestos products (including gaskets) other than fibre cement
products and friction materials (Appendix 3, Fig. 1C); and
? 6813 - Friction material and articles thereof (Appendix 3, Fig. 1D).
ABS data is the main source of Australia's foreign trade statistics. ABS obtains data
direct from ACS which is then analysed and collated (on a statistical month basis)
according to tariff code (classification), month, port of import and country of export.
ACS receives documentation submitted by exporters and importers (or their agents), as
required by the Customs Act 1901, Section 113 and Section 168. The documentation
includes information about the type, quantity and value of goods being imported and
exported. This includes names of importer, overseas suppliers and description of product
being imported. Information provided in the documentation is used by ACS to assess and
collect Customs duty and other revenue payable on imported and exported goods and to
facilitate the monitoring and control of the movement of goods into and out of Australia.
Non-confidential information is available to the public. Confidentiality restrictions are
placed on the release of statistics for certain commodities to ensure the confidentiality of
information relating to individual importers. These restrictions do not affect total export
and import figures, but they can affect statistics at all levels in country, commodity State
and port tables.
ACS and ABS classify information on imported and exported goods according to an
international convention (World Customs Organisation's Harmonised Commodity
Description and Coding System). This classification system cannot, of necessity,
individually distinguish between every item of commerce and it is common for codes to
include only the major sub-groupings of a particular type/group of product, such as
chemicals. Australia collects more detail than is provided for at the international level by
extending the 6-digit Tariff to a 10 digit description for imports.
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Chrysotile Asbestos
Survey information (methodology)
Survey 1. Survey on importation of chrysotile products (6811, 6812, 6813)
Surveys of importers were conducted seeking information on the importation and use of
asbestos products in Australia. Companies that were identified from the three customs
categories for asbestos products (6811, 6812, 6813) using 1994 ACS data, were surveyed.
Investigation of the import levels and use of automotive friction materials (e.g. brake
lining, brake disc pads, clutch facings and brake blocks) and gaskets in Australia was
limited to New South Wales and Western Australia due to the large number of import
companies identified for all of Australia.
Survey forms were sent to 263 companies who according to customs data, could have
been importing asbestos containing products, and responses were received from 137
companies, a response rate of 52%. Appendix 4 provides a summary of the results of the
surveys.
This information was supplemented by additional survey work in the automotive
manufacturing and importing industry, the automotive aftermarket industry and by
directly contacting companies that may be using chrysotile products in industrial
equipment and machinery, aircraft industry and other industries (e.g. coal and mining
industry).
Other uses of asbestos products in Australia (i.e. excluding friction materials and gaskets)
were also investigated. Customs data indicated the `other products' included fabricated
asbestos fibres, yarn and thread, cords and string, woven or knitted fabric, clothing and
accessories, footwear and headgear, paper, millboard and felt. This survey was carried
out nationally.
These surveys sought information on:
? type of asbestos products being imported and end-use of the products;
? alternative (non-asbestos) products in use;
? modification of asbestos products and the processes involved;
? control measures in place when using asbestos products;
? disposal of asbestos materials; and
? company policies in regard to the use of asbestos.
New car manufacturers and importers listed in these customs categories (6811, 6812 &
6813) were surveyed separately (survey 2).
Survey 2. Survey of companies importing and manufacturing new vehicles
A survey of importers and manufacturers of new vehicles was carried out in collaboration
with the Federal Chamber of Automotive Industries (FCAI). The aims of the survey were
to:
? provide an overview of the current market applications of asbestos and non-
asbestos products in the automotive industry for new vehicles;
148 Priority Existing Chemical Number 9
? identify situations where alternatives are available;
? identify company policies regarding asbestos products.
This survey investigated a range of vehicle types including passenger cars, commercial
trucks, buses, motorcycles, heavy trucks and coaches.
A total of 26 companies were surveyed, which included the top 10 car manufacturing and
importing companies in Australia namely Ford, Holden, Toyota, Mitsubishi, Hyundai,
Nissan, Mazda, Honda, Daewoo and Subaru (Federal Chamber of Automotive Industries,
March 1997). All 26 companies responded to the survey and clarification of certain
aspects of the survey was followed up by phone call. A list of the companies
participating in this survey can be found in appendix 5. These companies import and
manufacture a range of vehicles including passenger cars, trucks, light trucks and heavy
trucks.
Survey 3. End-use aftermarket survey
A small survey of the automotive aftermarket industry was conducted to gauge the
relative usage of both asbestos and non-asbestos products in garages and workshops and
to assess occupational exposure to chrysotile in the workplaces. Each of the workplaces
in the survey was visited. A questionnaire was completed at each workplace and air
monitoring for exposure to asbestos was conducted. The workplaces surveyed in Sydney,
NSW, were as follows: 5 service garages (4 car and 1 bus), 3 brake bonding workshops,
and one gasket-processing workshop.
In response to the questionnaire, the employer and employees at each workshop provided
information about potential exposure to chrysotile, type of work carried out, number of
workers and estimated duration of exposure. Part of the survey concerned the
management of risk, including control measures, training and disposal procedures. Each
workshop was asked about engineering controls and safe work practices that have been
implemented in the workplace to reduce exposure to asbestos.
At these workplaces, information was also sought on:
? usage of chrysotile and non-chrysotile products;
? labels and MSDS; and
? management policy and/or approach; and
Personal monitoring was conducted at all workshops using the method specified in the
Asbestos Code of Practice (NOHSC, 1988), that is, membrane filter sampling (MFM) and
phase-contrast optical microscopy (PCM). However, sampling was for less than the
specified 4 hours as work was task orientated (therefore results were not expressed as a
TWA). To supplement the personal monitoring results, a number of fixed point (static)
samples were taken in the work areas. Static monitoring was also conducted in areas of
the workplace away from the work areas to ascertain background fibre concentrations.
Some samples were analysed for mineral fibre types by Analytical Transmission
Microscopy (ATEM) using the NIOHS/TEM/MFM1 and MFM2. The analysis was
carried out using Phillips CM12 at a magnification of 8800X and fibrous minerals were
analysed using Energy Dispersive x-ray analysis (EDAX) and selected area electron
diffraction patterns (SAED). Fibre length and diameter were measured directly using the
149
Chrysotile Asbestos
pre-calibrated measurement mode of the instrument. Only respirable fibres of any length
were recorded i.e. those less than 3 祄 diameter, including any adhering particles; all
fibre lengths and diameters were recorded (NB This is different to the size of regulatory
fibres, which are fibre length > 5祄 and fibre diameters > 0.2 and < 3 祄).
150 Priority Existing Chemical Number 9
APPENDIX 3
ANALYSIS OF 1997 AUSTRALIAN CUSTOMS DATA ON
ASBESTOS AND ASBESTOS PRODUCTS
Figure 1A. Customs data for import of raw chrysotile during
1997
Qty (kg)
2524.00.00.01
Chrysotile (white) 820,522
Qty (kg)
2524.00.00
2524.00.00.02
ASBESTOS
Other asbestos* 735,000
151
Chrysotile Asbestos
Figure 1B. Customs data for import of fibre-cement products
during 1997
Qty (kg)
6811.10.00.15
Corrugated sheets 65,393
6811
Articles of asbestos- Qty (m2)
cement, of cellulose
fibre-cement or the 6811.20.00.16
like Other 545,137
sheets, panels
and similar articles
Qty (kg)
6811.30.00.17
tubes, pipes 650
and tube
or pipe fittings
Qty (Kg)
6811.90.00.18
other articles 3,482
KEY
- may or may not contain asbestos
152 Priority Existing Chemical Number 9
Figure 1C. Customs data for import of "other" products
containing asbestos (including gaskets) during 1997
Qty (kg)
6812.10.00.19
Fabricated asbestos fibres; 2,249
mixtures with a basis of asbestos
or with a basis of asbestos and
magnesium carbonate.
Qty (kg)
6812.20.00.20
Yarn and thread 14,868
Qty (kg)
6812.30.00.21
6812
Cords and string, whether 134
Fabricated asbestos
or not plaited
fibres; mixtures with
a basis of asbestos
Qty (kg)
or with a basis of
6812.40.00.22
asbestos and
Woven or knitted fabric 364
magnesium
carbonate; articles
of such mixtures or Qty (kg)
of asbestos (eg. 6812.50 00.23
thread, woven (kg) - Clothing, clothing accessories 272
fabric, clothing, footwear and headgear
headgear, footwear,
gaskets) whether or
Qty (kg)
not reinforced, other
6812.60.00.24
than goods of 6811
Paper, millboard and felt 68,339
or 6813
Qty (kg)
6812.70.00.25
Compressed asbestos fibre 122,627
jointing, in sheets or rolls
6812.90.10
Qty
Of a kind used as
replacement components in
6812.90 57 - Gaskets 59,811 (no. of articles)
passenger motor vehicles
Other
58 - Other 14,149 (kg)
Qty
6812.90.90
Other 59 - Gaskets 139,745 (no. of articles)
60 - Other 6411 (kg)
Note: All of these categories contain
asbestos
153
Chrysotile Asbestos
154 Priority Existing Chemical Number 9
155
Chrysotile Asbestos
156 Priority Existing Chemical Number 9
157
Chrysotile Asbestos
158 Priority Existing Chemical Number 9
APPENDIX 5
LIST OF COMPANIES INVOLVED IN THE `NEW VEHICLE
MANUFACTURING AND IMPORTING SURVEY'.
1. BMW Australia Ltd
2. Chrysler Jeep
3. Daewoo Automotive Australia
4. Diahatsu
5. Ford Motor Company Australia
6. General Motors - Holden
7. Honda Australia (Motorcycles and Power Equipment)
8. Honda Australia (Motor Vehicles)
9. Hyundai
10. International Trucks Australia Ltd
11. Jaguar Daimler
12. Kawasaki Motors Pty Ltd
13. Mack Trucks
14. Mazda Australia
15. Mercedes-Benz Australia
16. Mitsubishi
17. Nissan Australia
18. Rover Australia
19. Saab
20. Scania
21. Subaru
22. Suzuki Australia Pty Ltd
23. Toyota Australia
24. Volkswagen
25. Volvo Truck Australia
26. Yamaha Motor Australia
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Chrysotile Asbestos
160 Priority Existing Chemical Number 9
161
Chrysotile Asbestos
162 Priority Existing Chemical Number 9
163
Chrysotile Asbestos
164 Priority Existing Chemical Number 9
APPENDIX 7
ASBESTOS BANS/RESTRICTIONS IN SPECIFIC COUNTRIES
AUSTRIA
Legislation:
Ordinance of the Federal Minister of the Environment, Youth and the Family and of the
Federal Minister of Labour and Social Affairs of April 10, 1990, Concerning Restrictions
on the Placing on the Market, the Manufacture, Use and Labelling of Substances,
Preparations and Finished Products which Contain Asbestos.
Prohibitions:
Manufacture, placing on the market and use of products containing substances,
preparations or finished products of which asbestos of the amphibole group is a
component (actinolite, amosite, anthophyllite, crocidolite and tremolite); and certain
products containing substances, preparations or finished products of which asbestos of the
chrysotile type is a component.
Seventeen classes of chrysotile product are listed as prohibited, including: toys; smoking
articles, paints; putties, glues; catalytic screens and insulating means intended for us in
connection with LPG-fuelled heating devices; pulverised substances and preparations in
powder form dispensed by retailers; substances and preparations applied by spraying;
fiber-reinforced polymers and asphalts; mortars and fillers; floor and road-surfacing
materials; filters and auxiliary filter materials, except diaphragms used in electrolytic
processes; light-weight construction panels (volume weight <1.0 g/cm3); insulating
materials or insulants (e.g. felts, papers, paper-boards) for fire protection, sound
insulation, thermal insulation, cold insulation and moisture-proofing; thermal-protection
clothing for temperature below 500篊.
Seals and packing, and friction linings for machinery and industrial equipment are on the
list, with the qualification that they may be subject to exemptions contained in the
Ordinance (see below).
Brake and clutch linings for vehicles containing asbestos are prohibited from being placed
on the market, if the technology and road laws allow the use of linings without asbestos of
at least equivalent effectiveness, and if such linings are available. There is provision for
the government to issue each year a list of vehicle types, for which linings not containing
asbestos are available.
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Chrysotile Asbestos
Exemptions:
Government may permit certain uses where it does not effect employee health and safety,
and a where the manufacturer or importer has demonstrated by way of a State authorised
expert opinion that no substitute substances are available which constitute a lower health
hazard or no hazard at all, or that only asbestos-containing replacement parts can be used
due to specific design conditions.
Comments:
Information provided by the Austrian government is that the publication of the list of
vehicle types for which asbestos linings are permitted, has ceased to occur as there are
almost no cars needing brakes or clutches made with asbestos.
Asbestos-cement products for building applications were banned from January 1994.
166 Priority Existing Chemical Number 9
DENMARK
Legislation:
Order No. 660 of 24 September 1986, as amended by Order No. 984 of 11 December
1992, on Asbestos.
Prohibitions:
Prohibited to manufacture, import, use or work with asbestos or asbestos-containing
material in any form.
Time limitations were implemented for the following:
1. Until 31 December 1986:
manufacture of roofing and surface materials of asbestos cement for external use; use of
same permitted until 30 June 1987.
2. until 31 December 1987:
import of asbestos apart from crocidolite and amosite for external cement products
(corrugated plates, hand-moulded goods for roofing), use of same permitted until 30 June
1988.
3. until December 1989:
import and use of asbestos other than crocidolite or amosite in commutators.
4. until 30 June 1989:
lifts with asbestos-containing friction materials.
Exemptions:
The following items were given indefinite exemption (`until further notice') from the ban:
1. manufacture, import or use of asbestos or asbestos-containing material, apart from
crocidolite and amosite, for bonded gasket material (except for gaskets used for water
systems with a temperature of under 110 deg C, which is prohibited);
2. closed metal asbestos packing (e.g. copper asbestos packing);
3. rubber asbestos packing and similar packing;
4. friction materials (containing max 70% asbestos); (also see comments below); and
5. bearings based on phenolic resin (containing max of 50% asbestos) for use on board ships
in accordance with the requirements of the classification companies (this signifies that the
use of these materials is very limited, mainly for propeller shaft bearings).
Comments:
Under Order No. 660, motor vehicles and trailers and technical equipment that are
provided with asbestos-free friction linings by the manufacturer are required to use
asbestos free linings when the originals are replaced. Furthermore, if other vehicles or
167
Chrysotile Asbestos
technical equipment can be provided with asbestos-free linings according to a declaration
from the manufacturer or a test report from an approved testing laboratory, then as of 30
June 1988 these were required to be used. In 1988, a regulation came into effect
according to which all new cars had to be equipped with asbestos-free linings. In 1993 a
list of `old' cars which still may be equipped with asbestos-free linings was issued. A
comment has been made by Danish authorities that a mandatory system of tests every
second year for cars older than 4 years is being introduced and it is expected to eliminate
many older cars still running on the roads.
Order No. 540 of 2 September 1982 on Substances and Materials, Section 19, applies the
principle of substitution to the exemptions listed above. It states that a substance or
material which may constitute a danger to or in any other way adversely affect safety or
health shall not be used if it can be replaced by a harmless, less dangerous or less harmful
substance or material.
Exemptions to the ban on asbestos may be granted by the Danish Arbejdstilsynet,
however they have stated this happens rarely and only under limited time restraints.
168 Priority Existing Chemical Number 9
FRANCE
Legislation:
Decree No. 96-1133 of 24 December 1996 Relating to the Banning of Asbestos.
Prohibitions:
Prohibits the manufacture, modification, sale, import, export, placement on the national
market, possession for the purpose of sale, supply and transfer for any reason whatever, of
all forms of asbestos and asbestos-containing products or devices.
Prohibitions do not apply to pre-existing materials and listed products or devices
containing chrysotile, where an alternative cannot be found that could fulfil the same
function as the chrysotile fibre, and that could:
(a) present, according to current scientific knowledge, a lesser risk than chrysotile to the
worker dealing with these materials or devices; and
(b) fulfil all the technical safety criteria applied to the final product.
Exemptions:
1. Until 31 December 2001:
The prohibition of possession with a view to selling, placing on the market and transfer
for whatever reason, will not apply to second hand vehicles or to stipulated vehicles and
agricultural and forestry machinery which were in circulation prior to the decree coming
into force; and
Listed products:
1. Until 1 January 1998:
Thermal isolation devices used in industry for temperatures between 600篊 and 1000篊;
2. Until 1 January 1999:
Friction linings for heavy industrial equipment and installations, certain machines and
vehicles greater than 3.5 tonnes;
Friction components for compressors and vacuum pumps with pallets.
3. Until 1 January 2002:
Friction linings for aircraft;
Seals and linings used for watertightness in industrial processes of high temperature or
pressure;
Diaphragms used in the production of chlorine and oxygen in nuclear submarines;
Thermal isolation devices used in industry for temperatures above 1000篊.
Comments:
Prohibitions do not relate to waste disposal.
169
Chrysotile Asbestos
List of exemptions to be reviewed annually.
Importer/introducer must make annual declaration to the Minister for Employment in
relation to activities involving listed exempt articles. In practice, the list of derogations is
very limited.
The French Government commissioned the Institute National de la Sante et de la
Recherche Medicale (INSERM) Expert Panel on Asbestos to undertake a report (Effects
on the Health of the Main Types of Asbestos, June 1996), the main finding of which, was
that action is needed to reduce the burden of asbestos-related tumours in the French
population. The findings of this report have been critised by a number of expert bodies,
including the Royal Society of Canada, who claim that the INSERM report omits a
number of key studies, uses an inappropriate risk model (overestimating risks from
current exposures) and provides little new information.
170 Priority Existing Chemical Number 9
GERMANY
Legislation:
Ordinance on Bans and Restrictions on the Placing on the Market of Dangerous
Substances, Preparations and Products of 14 October 1993 - pursuant to the Chemicals
Act.
Prohibition:
Specified substances and preparations may not be placed on the market. Chrysotile,
together with other forms of asbestos, is subject to this prohibition with the following
exemptions.
Exemptions:
1. Replacement parts containing chrysotile for maintenance purposes where no other
suitable parts are available;
2. Renewed placing on the market of vehicles, devices and systems which contain asbestos
products and were manufactured before 14 October 1993; and
3. Naturally occurring mineral raw materials containing free asbestos fibres in a
concentration not exceeding 1% asbestos by weight.
At the time of the ban coming into force (14 October 1993), temporary exemptions were
introduced for some categories of chrysotile-containing articles as follows:
1. Until 20 April 1994:
Asbestos preparations and products manufactured before 14 October 1993, except for:
toys, finished products in powder form for sale in retail outlets; smoker's articles;
catalytic screens and insulating devices intended for or installed in heating equipment
powered by liquid gas; coatings; substances or preparations for spraying; crocidolite and
preparations and products containing crocidolite.
2. Until 31 December 1994:
Clutch linings for vehicles, where no asbestos-free alternatives are available from a safety
point of view;
Brake shoe inserts for rail vehicles, where no asbestos-free alternatives are approved
under transport legislation;
Friction pads for industrial applications; and
Static seals, dynamic seals, packings and cylinder head gaskets for vehicles and industrial
use.
3. Until 31 December 1999:
Diaphragms for electrolytic processes where asbestos free substitutes are not available on
the market or their use gives rise to unreasonable hardship;
171
Chrysotile Asbestos
4. Until 31 December 2010
Asbestos containing raw materials for the manufacture of chrysotile-containing
diaphragms for chlor-alkali electrolysis in existing systems where asbestos free
substitutes are not available on market or their use gives rise to unreasonable hardship.
Comments:
Ban does not apply to demolition or repair of buildings containing asbestos material or to
waste disposal.
Information provided from the German government indicates that since the period of
expiry for the temporary exemptions listed above, special permission is required from the
Government in order to use these previously exempt articles. However only a few
permissions have been granted, relating mainly to brake linings for old industrial lifts and
lorries.
172 Priority Existing Chemical Number 9
ITALY
Legislation:
Law 27 March 1992, n.257: Regulations relating to the cessation of the use of asbestos.
Prohibitions:
Extraction, import, export, marketing, manufacture of asbestos and products containing
asbestos.
The regulation contained one or two year `phase-in' dates for the prohibition to become
effective for the following applications:
1. until 27 March 1994:
Friction gaskets for motor vehicles, industrial machines and plants; and
Filters and auxiliary means of filtration for production of beverages
2. until 27 March 1995:
Large-sized asbestos sheets, flat or corrugated
Tubes, piping and containers for transport and storage of fluids, for both industrial and
public use
Friction gaskets, spare parts for motor vehicles, railway vehicles, industrial machines and
plants with special technical characteristics
Gasket heads for older type motor vehicles
Static plate joints and dynamic gaskets for components subject to strong stresses
Ultrafine filters for sterilisation and production of beverages and medicinals
Diaphragms for electrolysis processes
173
Chrysotile Asbestos
NETHERLANDS
Legislation:
Asbestos-Free Friction Materials Decree (19 September 1991) (no. 507); Asbestos
Decree (Working Conditions Act)(1993) (no.136); Commodities Decree on Asbestos (15
August 1994).
Prohibitions:
Production, use, and supply of all types of asbestos and asbestos-containing products are
prohibited.
Exemptions:
Exemptions to the prohibition on the production and use of asbestos and asbestos-
containing products can only be given when it is impossible to produce or use asbestos-
free products that are less dangerous than asbestos-containing products. Exemptions to
the prohibition on supply can only be given when an exemption has been granted for the
production and use of the products concerned.
Exemptions are divided into general exemptions and exemptions given to an individual
company. General exemptions are:
1. Laboratory research on asbestos and asbestos containing products;
2. Storage of asbestos waste;
3. Supplying asbestos and asbestos containing products for conveying in transit to another
member state of the EU;
4. Production, application and supply of asbestos (except blue asbestos) containing friction
materials when these actions relate to motor vehicles on more than 3 wheels with a mass
greater than 3500 kilograms or with a velocity less than 50 kilometers per hour;
5. Production, application and supplying of asbestos (except blue asbestos) containing
friction materials when these actions relate to motor vehicles on more than 3 wheels with
a mass less than 3500 kilograms and with a velocity above 50 kilometers per hour, when
for these motor vehicles no asbestos-free friction materials are available or when these
motor vehicles were introduced onto the market before October 1 1985;
6. Until July1, 1998:
Application and supplying of asbestos containing packing in seals, intended to function
under high temperatures and high pressure, which are put into use before July 1, 1995 and
which can't be replaced by asbestos-free products which are not or less dangerous; and
7. Until July 1, 1988:
Use, filling and supplying of asbestos containing cylinders for the storage of acetylene
gas, which are put into use before July 1, 1993.
Specific (temporary) exemptions given to individual companies up to the period ending
January1 1997 were:
174 Priority Existing Chemical Number 9
8. Until September 30 1997:
Application of white asbestos containing seals in a production plant for liquid chlorine,
and in relation to shipment and transport of fluid chlorine, as long as no asbestos- free
alternative is available;
9. Until December 31 1997:
Production, application and supplying of asbestos (except blue asbestos) used for the
production of chlorine in a diaphram-electolysis plant, as long as no asbestos-free
alternative is available;
10. Until January 1 1998:
Application and supply of asbestos (except blue asbestos) containing packing for
application in a desulphuring installation, as long as no asbestos-free alternative is
available; and
11. Until January 1 1999:
Application and supply of asbestos (except blue asbestos) containing packing for
application in "Flexicoker" systems, as long as no asbestos-free alternative is available.
Comments:
Information provided from the Netherlands government is that a ban was introduced on
spray-on asbestos and the use of blue asbestos in 1978. Since 1983 trade in asbestos has
been limited exclusively to "tightly-bonded" asbestos products. As a result of an inquiry
into the availability of asbestos-free friction materials for vehicles, the government is
considering extending the ban to include vehicles with a mass above 3500 kilograms.
Some problems with the use of asbestos-free friction materials in vehicles produced
before October 1 1985 is anticipated.
175
Chrysotile Asbestos
NORWAY
Legislation:
Regulations laid down by the Ministry of Local Government and Labour 1991 under the
Working Environment Act.
Prohibitions:
Prohibits the import, manufacture, sale, use, and other handling of asbestos or products
containing asbestos (defined as the fibrous crystalline silicate materials chrysotile,
crocidolite, amosite, anthophyllite, tremolite, and actinolite), unless an exemption is
granted by the government or an exemption exists under Chapter 3 of the regulations, as
follows:
Exemptions:
Under Chapter 3 of the regulations, there are exemptions for:
1. Use of friction components, gaskets and filling compounds, if it is impossible to
manufacture or use products of this kind with a content less harmful to health;
2. Repair with asbestos of technical devices which contain asbestos or material containing
asbestos (other than friction components and gaskets), when it is impossible to use a
substance less harmful to health;
3. Demolition or repair of buildings or technical installations which include asbestos
material; and
4. Mining and milling of rocks containing a maximum of 1% asbestos by weight.
Comments:
Information provided by the Norwegian government indicates that dispensation from the
regulations, although possible, is rarely given.
The government has also indicated that most vehicles, both new and older models, are
now fitted with asbestos free friction linings. A list of vehicles in Norway and Denmark
which may use friction linings containing asbestos was published by the Norwegian
National Association of Car Importers in 1993.
176 Priority Existing Chemical Number 9
SWEDEN
Legislation:
Ordinance of the Swedish National Board of Occupational Safety and Health Containing
Provisions on Asbestos, together with General Recommendations on the implementation
of the Provisions (AFS 1992:2).
Ordinance Prohibiting Asbestos-Containing Friction Linings in Vehicles (SFS 1986:683
and 684).
Prohibitions:
AFS 1992:2 ?prohibits the use, machining/processing or treatment of asbestos and
materials containing asbestos, subject to certain exemptions indicated in sections 5-8 of
the legislation (see below). Exemptions, however, do not apply to crocidolite and
materials containing crocidolite.
SFS 1986:683/684 - prohibits the fitting of asbestos-containing friction linings in the
following vehicles when offered for sale or transfer:
1. Passenger cars and motor cycles classed as 1988 or subsequent models for
registration or type inspection;
2. Lorries and buses classes as 1989 or subsequent models for registration inspection or
type inspection; and
3. Other motor-powered vehicles and trailers manufactured from 1st July 1988 onwards.
A special statutory instrument lists vehicles manufactured prior to the above dates for
which asbestos-free friction linings are available. The selling or commercial transfer of
asbestos friction linings for these vehicles is also prohibited.
Exemptions:
AFS 1992:2 - sections 5-8
1. Asbestos and material containing asbestos may be used by permission of the National
Board of Occupational Safety and Health if it is not possible for less deleterious material
to be used and the emission of asbestos-containing dust is prevented;
2. Brake linings and other frictional elements containing asbestos may be used,
machined/processed and treated if no acceptable products of less deleterious material are
available. Frictional elements must be handled so that the emission of asbestos dust is
prevented;
3. Gaskets containing asbestos may be fitted to engines manufactured before 1987 if no
acceptable products of less deleterious material are available;
4. Technical devices and structural parts which include asbestos or material containing
asbestos (other than brake linings and frictional elements), may be used as long as the
177
Chrysotile Asbestos
asbestos-containing material is not interfered with and if the emission of asbestos-
containing dust is prevented;
5. Asbestos and asbestos-containing material may not be replaced with other such material
in connection with repair or service without permission; and
6. Asbestos and material asbestos-containing material may be machined/processed and
treated by permission of the Labour Inspectorate.
Comments:
Information from the Swedish National Board of Occupational Health and Safety
indicates that it is very restrictive in the granting of permits for the use of asbestos
gaskets. Permission is usually only granted in cases where the fitting of asbestos gaskets
is a requirement for certification or official approval e.g. in aircraft. The trend is for a
decline in the number of permits being issued. More than 100 were issued in 1987-88,
whereas only 5 were issued from January to September 1997.
178 Priority Existing Chemical Number 9
SWITZERLAND
Legislation:
Ordinance relating to Environmentally Hazardous Substances (Ordinance on Substances)
of 9 June 1986.
Prohibitions:
Prohibits the use, supply and importation of asbestos and asbestos-containing products or
articles as commercial goods from 1 March 1990. The following classes of asbestos-
containing products or articles were prohibited from the dates specified:
1. From 1 January 1991:
Large-size flat panels and corrugated sheets; pipes for house drainage; filters and filter
aids for drink manufacture.
2. From 1 January 1992:
Friction linings for motor vehicles, machines and industrial plants.
3. From 1 January 1995:
Pressure and sewage pipes; spare friction linings for motor vehicles, rail vehicles,
machines and industrial plants with particular design conditions; cylinder head gaskets for
older types of engine; static flat packing and dynamic packing for high demand
applications; very fine filters and de-germinating filters for the manufacture of drinks and
pharmaceutical products; diaphragms for electrolysis processes.
Exemptions:
The government may grant permission for a manufacturer or trader to continue to supply
certain of the products specified above after the dates laid down provided that:
1. according to the state of the art, there is no replacement substance for the asbestos and
provided that no more than the minimum amount of asbestos necessary is employed for
the desired purpose, or
2. only spare parts containing asbestos can be used because of particular design constraints,.
The use of chrysotile for motor vehicles is permitted insofar as it is permitted under the
provisions of the EU Council Directive 76/769 (Approximation of the Laws of Member
States relating to Restrictions on the Putting into Circulations and Use of Certain
Hazardous Substances and Preparations).
Comments:
Notes on regulations made in connection with this Ordinance (Regulations Concerning
Materials Harmful to the Environment) were supplied by the Swiss Government (Notice
No. 20 May 1990). These notes clarify the situation regarding asbestos-containing vehicle
parts in vehicles imported or manufactured in Switzerland, and asbestos-containing
vehicle parts for use in the aftermarket. Briefly, seals and gaskets in new motor vehicles
179
Chrysotile Asbestos
were prohibited from 1.10.95; friction linings from 1.10.92 and other parts from 1.10.90.
Spare parts containing asbestos may continue to be exchanged for spares also containing
asbestos in vehicles with "special construction conditions" (defined as cases where
replacing a part containing asbestos by an asbestos-free spare part would involve making
alterations to other components of the system concerned as regards dimensioning or
materials). In the case of asbestos-containing replacement parts for vehicles without
"special construction conditions", replacement friction linings, seals and gaskets were
prohibited from 1.10.95 and other spare parts from 1.10.90.
180 Priority Existing Chemical Number 9
UNITED KINGDOM
Legislation:
The Asbestos (Prohibitions) Regulations (1985, as amended in 1992).
Prohibitions:
The importation into the UK of crude fibre, flake, powder or waste amphibole asbestos
(amphibole defined as crocidolite, amosite, fibrous actinolite, fibrous anthophyllite,
fibrous tremolite and any mixture containing one or more of these minerals), the supply of
amphibole asbestos or any product to which amphibole asbestos has been intentionally
added, the use of amphibole asbestos or any product to which amphibole asbestos has
intentionally been added in the manufacture or repair of any other product, the use of any
product containing amphibole asbestos, asbestos spraying (asbestos defined as amphibole
and chrysotile), and the supply and use of any product containing chrysotile listed in the
Schedule to the Regulations.
Categories of chrysotile-containing products specified in the Schedule as prohibited are:
materials or preparations intended to be supplied by spraying; paints or varnished; filters
for liquids, except for filters for medical use until 31 December 1994; road surfacing
material where the fibre content is more than 2%; mortars, protective coatings, fillers,
sealants, jointing compounds, mastics, glues and decorative products in powder form and
decorative finishes; insulating or soundproofing materials which when used in their
intended form have a density of less than 1g/cm3; air filters and filters used in the
transport, distribution and utilisation of natural gas and town gas; underlays for plastic
floor and wall coverings; textiles finished in the form intended to be supplied to the end
user unless treated to avoid fibre release, except for diaphragms for electrolysis processes
until after 31st December 1998; roofing felt after 1st July 1993.
Exemptions:
1. The Government may exempt any person or class of persons from all or any of the
prohibitions by a certificate in writing from the Health and Safety Executive, subject to
certain conditions, including that it is satisfied that the health or safety of persons likely to
be affected by the exemption will not be prejudiced as consequence;
2. In relation to chrysotile, the prohibition does not apply to the use of any product which
was in use before 1st January 1993 unless it was subject to prohibition by the Asbestos
(Prohibitions) Regulation 1985, which this legislation revokes;
3. Prohibition does not include any activity in connection with the disposal of a chrysotile
product; and
4. Chrysotile products not listed in the Schedule would be considered exempt, including
brake linings, clutches and gaskets.
181
Chrysotile Asbestos
Comments:
These Regulations implement relevant EU Directives.
Prohibition does not apply to any chrysotile product not listed in the Schedule to the
Regulation. As a result, friction materials such as brake and clutch linings, and gaskets
containing chrysotile are not prohibited.
The UK Health and Safety Commission has submitted a recommendation to the Secretary
of State to extend the scope of the existing EU ban on asbestos to cover all uses
(including marketing and supply) of chrysotile, except for a limited number of essential
uses where there are no satisfactory alternatives available. (HSE Press release - 17
February 1997).
Other UK legislation relevant to asbestos is: Control of Asbestos at Work (CAW)
Regulations 1987; Asbestos (Licensing) Regulations (ASLIC) 1993. Recent proposals
(by the HSC) to `tighten' these regulations (HSE Press Release ?11 March 1998)
include:
1. Extend licensable work;
2. Tighten the exposure limits for chrysotile asbestos;
3. Place a duty on employers to ensure that where respiratory protective equipment
(ERP) is required, it is chosen to reduce exposures to as low a level as reasonably
practicable and not just to the exposure limit;
4. Put a duty on employers to provide refresher training to workers;
5. All work liable to lead to asbestos exposure must comply with the requirements of
CAW
HSC plans to issue a Consultative Document by mid-1998 on recommended changes to
these regulations, which are scheduled to come into force in 1999 (HSE News Release
February 1997).
182 Priority Existing Chemical Number 9
UNITED STATES
Legislation:
Asbestos Ban and Phase Out (ABPO) Rule of 12 July 1989.
Prohibitions:
Asbestos (including chrysotile) containing substances not being manufactured, imported
or processed at the time of promulgation of the Rule, namely: corrugated paper, rollboard,
commercial paper, specialty paper, flooring felt, and new uses of asbestos.
Exemptions:
Products on the market prior to the promulgation of the rule, which include: disc brake
pads, drum brake linings, clutch facings, gaskets, asbestos cement sheeting, shingles and
piping, roofing felt, millboard, pipeline wrap, vinyl-asbestos tiles and asbestos clothing.
Comments:
The ABPO rule was intended to reduce exposure and health risks by imposing a phased
ban (over 7 years) on asbestos products and requiring labelling on those products still in
commerce as the phase out progressed.
The Fifth Circuit Court voided much of the ABPO Rule in October 1991, leaving only
those items described above as banned.For further information on this court decision see
Section 10.2.2
Priority Existing Chemical Number 9
183
APPENDIX 8
EXPORT DATA ON CERTAIN PRODUCTS WHICH CONTAIN
(OR MAY CONTAIN) ASBESTOS
Customs category Period (yr) Quantity (kg) Cost ($A)
6812.90.00* 189,000
8,704
1990-1991
Articles of asbestos or 351,000
38,387
1991-1992
of mixtures with a basis
216,000
9,161
1992-1993
of asbestos or with a
1,410,000
76,968
1993-1994
basis of asbestos and
289,000
8,617
1994-1995
MgCO3
(this category should 531,573
8,417
1995-1996
contain gaskets) 1,195,795
45,893
1996-1997
876,891
21,704
1997-1998
Quantity (number)
6813.10.00** 574,000
204,994
1990-1991
Brake linings and pads, 502,000
210,601
1991-1992
not mounted, with a
1,261,000
240,775
1992-1993
basis of asbestos, of
1,508,000
351,463
1993-1994
other mineral
1,633,000
256,610
1994-1995
substances or of
cellulose 1,463,289
215,027
1995-1996
956,320
161,714
1996-1997
1,148,140
120,503
1997-1998
6813.90.10** 185,000
32,176
1990-1991
Transmission linings, 89,000
12,462
1991-1992
not mounted, with a
156,000
25,771
1992-1993
basis of asbestos, of
190,000
35,829
1993-1994
other mineral
338,000
46,999
1994-1995
substances or of
cellulose 125,256
23,354
1995-1996
201,619
N/A
1996-1997
549,837
36,164
1997-1998
6813.90.90** no entries made 71,000
1990-1991
Friction material and 75,000
1991-1992
articles thereof, not
99,000
1992-1993
mounted, for clutches
959,000
1993-1994
or the like, with a basis
292,000
1994-1995
of asbestos, of other
mineral substances or 310,349
1995-1996
of cellulose (excl. 206,899
1996-1997
brake linings and pads
1,851,454
1997-1998
or transmission linings)
*all asbestos
**may or may not contain asbestos
N/A = data provided was incomplete due to a transcription error
184 Priority Existing Chemical Number 9
APPENDIX 9
STUDIES ON THE RELATIONSHIP OF AGE TO SAFETY OF
THE AUSTRALIAN CAR FLEET
CSIRO study
A 1996 study by the CSIRO (using ABS statistics and a subset of data on reported crashes
in NSW over the period 1977-1993,) analysed the effect of an aging NSW car fleet on
road safety. The study noted that the age of the Australian car fleet has increased steadily
over the past 20 years, with the median vehicle age increasing from about 5.3 years in
1970 to about 8.5 years in 1993 (these figures are consistent with more recent ABS
statistics on age of the car fleet, reported in Section 5.4.1). The study showed that cars, in
which an occupant casualty or fatality was reported, tended to be older than the general
population of registered cars, and that this age difference increased over the period
studied. The study data was insufficient to determine whether the increased incidence of
`old vehicle' involvement in accidents was due to (i) the deterioration of vehicle systems
in old cars, (ii) the continued use of old cars preventing new cars and their improved
safety features from penetrating the market, or (iii) non-car effects, such as driver
characteristics. However, it was concluded that reduction of the average age of cars in
1993 to that in 1977, would have resulted in a saving of 43 fatalities and 1,002 casualties
(CSIRO, 1996).
Monash University Accident Research Centre study
The Monash University Accident Research Centre has also undertaken research into the
relationship between `crashworthiness' (the relative safety of vehicles in preventing
injury in crashes) and year of vehicle manufacture. Using crash data from 1987-1996, the
study measured the risk of the driver being killed or admitted to hospital as a result of
involvement in a `tow-away' crash. The study showed an improvement in
crashworthiness over the period of study (vehicles manufactured from 1964 to 1996),
with greatest gains over the years 1970-1979 and 1989-1996 (Newstead et al., 1998).
An associated project (Cameron, 1995) estimated the potential impact on total road
trauma (deaths and hospital admissions) of replacing older cars with new cars. Estimates
for the percentage reduction in road trauma, the number saved annually and social costs
saved annually were made for two different scenarios for two periods. The results are
shown in the following table.
Estimated savings from replacement of older cars involved in accidents
with new cars (Cameron, 1995)
Saving in driver deaths and Pre-1970 cars Pre-1980 cars
hospital admission costs replaced by new cars replaced by new cars
Estimated savings if new cars had replaced older cars crashing in 1987-92
Percentage reduction 2.4% 16.4%
Number lives saved (per annum) 242 1652
Social costs saved (per annum) $31 million $207.5 million
Estimated savings if new cars had replaced older cars crashing in 1995
Percentage reduction 0.43% 4.4%
Number lives saved (1995) 43 442
185
Chrysotile Asbestos
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