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Brit. J. induslr. Med., 1973, 30, 180-186
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In 1964 the Geographical Pathology Committee of the International Union against Cancer
(UICC) set up a working group on asbestos anc cancer and later issued a Report ana Recom
mendations (1965). A further meeting was held at the International Agency for Research
on Cancer (IARC), Lyon, France, on 5 and 6 October 1972. Tr.is was organized jointly with
the Medical Research Council Pneumoconiosis Research Unit. The report and recommenda
tions given here will also be published by IARC in 1973, together with the complete pro
ceedings of the meeting. The Committee consisted of three panels--Epidemiology, Pathology,
and Physics ar.d Chemistry.
The panels met in separate sessions and at the final session (Chairman Dr. J. C. Gilson) prepared this report to the Director of the International Agency for Research on Cancer.
Terms of reference
1. The Committee was to report on the present
evidence relating exposure to asbestos dust to
cancers, especially that obtained since the meeting of
the UICC Working Group on Asbestos Cancers in
1964.
2. The Committee was to make recommendations
for further research and indicate priorities for work of
immediate and long-term value.
*
in several countries. The Agency has done this as part of their wider programme of investigating environmental carcinogens. Common memberships between the UICC sub-committee and the com mittee advising the IARC ensured continuity of policy.
In October 1972 the IARC held an international conference with 137 participants from 20 countries to review all the evidence relating asbestos to cancers. Subsequently the Advisory Committee prepared its report which is divided into two sections, first, a general review in the form of answers to a number of important general questions about the relation of asbestos to cancers of different sites and, secondly, recommendations for further research.
Co-ordination of international co-opcration
Following the meeting of the UICC Working Group on Asbestos and Cancers in 1964, a sub committee of the UICC Commission on Geo graphical Pathology and Environmental Carcino gens (Chairman Dr. J. Higginson) was formed to co-ordinate work required to achieve the recom mendations.
In April 1970 agreements between the UICC and the IARC led to the winding up of the UICC sub-committee and the IARC taking on respon sibility for she sub-committee's woik and extending it by supporting certain projects on asbestos cancers
General review
1. Are all major commercial types of asbestos able to cause lung carcinoma?
Yes. Since 1964 the evidence of a causal rela tionship has been increased cy epidemiological studies showing exposure-r^sror.se relations for the incidence of hir.g carcinomas. The production of bang carcinomas in certain animals by all l>pes of asbestos svppeits this conclusion. The epidemio logical evidence in man. however, shows that there are clear d.Terences in risk with type of fibre and nature of exposure.
ISO
Report o f the Advisory Committee on Asbestos Cancers 181
2. Js (here evidence of an increased risk of lung carcinoma at low levels of expo5u;c to asbestos, such as have been encountered by the general population in urban areas?
The evidence of an exposure-response relationship based in part on past du>i measurements and in part on the type of job within the industry suggests that an excess lung carcinoma risk is not detectable when the occupational exposure has been low. These low occupational exposures have almost certainly been much greater than that to the public from general air
pollution. 3. Since 1964 has the evidence relating past exposure
to asbestos and mesotheliomas changed? The evidence has been greatly strengthened by further prospective and retrospective mortality studies in many countries of populations exposed to asbestos. There is evidence that all commercial types of asbestos except anthophvllitc may be responsible. Evidence for an important difference in risk in different occupations and with the type of asbestos has increased. The risk is greatest with crociaolite, Jess with amosite, and apparently less v. ith chrysotile. With amosite and chrysotile there appears to be a higher risk in manufacturing than in mining and milling. There is also evidence from population studies that a proportion of cases of mesothelioma have no know n association with exposure to asbestos.
4. Js there evidence of an increased risk of meso-
thelial cancers at low levels of exposure to asbestos, such as have been encountered by the general population in urban areas? There is evidence of an association of ntesothelial tumours with air pollution in the neighbourhood of crocidolite mines and of factories using mixtures of asbestos fibre types. The evidence relates to con ditions many years ago. There is evidence of no excess risk of mesotheliomas from asbestos air pollution which has existed in the neighbourhood of chrysotile and amosite mines. There are reported differences on incidence of mesothelioma between urban and rural areas, the causes of which have not been established. There is no evidence of a risk to the general public at present. 5. Since 1964 has the evidence changed on the importance of other factors such as cigarette smoking, waxes, oils, and trace elements as con tributory factors to the cancer risk? The evidence has accumulated indicating: (1) Cigarette smoking is an important factor enhancing the lung carcinoma risk in asbestosexposed workers, in both men and women. Asbestos workers have specially strong grounds for giving up smoking to protect their health. No association has been demonstrated between cigarette smoking and mesotheliomas. (2) Animal experiments designed thus far to test
the importance of waxes and oils as contributory
factors in the production of mesothelioma have
shoxn that these contaminants are unlikely to be
relevant.
(3) From animal experiments there are no good
clues suggesting that trace elements are likely to be a
major factor in the production of asbestos cancers.
6. What other tyres of cancerare related toexposure
to asbestos? Prospective surveys of occupational groups
exposed to asbestos have in general shown a smalt
excess risk of seme other types of cancers (in
addition to bronchial and mesoikcHsl), especially
those of the gastrointestinal tract. The excess of these
tumours is relatively small compared v.ith that for
bronchial cancer. Evidence for an association with
ovarian tumours has not been supported by the
first large mortality survey of women previously
exposed to asbestos.
7. Is there evidence of an increased risk of cancer
resulting from asbestos fibres present in water,
beverages, food or in the fluids used for the ad
ministration of drugs?
Such evidence as there is does not indicate any
risk.
8. Is there evidence of a risk of lung fibrosis from
low levels of exposure to asbestos such as have
been encountered by the general population in
urban areas? There is at present no evidence of lung damage by
asbestos to the general public. The amount of
asbestos in the lungs of members of the general
public is very' small compared with the lungs of those
occupationally exposed. It is greatest where asbestos
is mined or worked and lowest in rural areas.
9. Has the relationship between asbestos exposure
and the development of pleural plaques been
established ? Pleural plaques have been associated with past
exposure to all commercial types of asbestos. But
additional factors, other than asbestos itself, are
involv ed. The plaques may remain fibrous or become
calcified. Not all pleural plaques are associated with
asbestos.
'.
` Recommendations for further research
Projects which the panels rated high in priority are marked *; those which will require close co-opera tion between the Panels are marked ?.
Epidemiology
The panel agreed that asbestos-related cancers occur in several sites in the body. The incidence of the different cancers varies with a number of definable factors and for other reasons, such as competing causes of death. Epidemiological studies will usually
182 Report o f the Advisory Committee on Asbestos Cancers
provide information on more than one type cf cancer. manufacturing and application sections of the
Research directed at only a single type may, on industry than in the mining and milling of this type
occasions, be useful, but in general the inevitable of fibre. What are the important factors in this uncertainties, in some cases in the differential reported difference?
diagnosis of, for example, peripheral lung car (c) Crocidohte Further studies are required in
cinomas and pleura! mesotheliomas, and between occupational groups exposed only to crocidolire or
peritoneal mesotheliomas and other intra-abdominal amosite or chrysotile in manufacturing and applica
cancers, will require that more than one type is tion parts of the industry' to establish more dearly
Studied at the same time.
differences in risks due to different fibres.
The panel recognized that some of the epidemio
Studies of the amount and type of asbestos in
logical projects'could be1pursued o n ly if there was the lungs of cases of rriesotnclioma fif possible by
close co-operation between epidemiologists, patholo cell type) in (a) a national survey of mesotheliomas,
gists, physicists and chemists, and others, because and (b) representative samples of cases arising in
their success will depend upon the development of groups with a definable past exposure.
improved techniques, some of which are referred to (5y* Studies of secular changes in the incidence of
in the recommendations of the other two panels.
pleural and peritoneal mesotheliomas nationally and
internationally.
Projects
(1) Further development of objective methods for
early detection and surveillance of effects caused by
asbestos: Topics for particular study include
(o) immunological techniques for screening for
fibrosis and neoplasia,
(b) functional tests of changes in the peripheral
airways,
(c) detection of pleural thickening,
(6) * Epidemiological studies to investigate the association between past exposure to asbestos and cancer of sites other than lung, pleura, and peri toneum.
(7) Studies of secular trends in the asbestos content of the lungs in the general population.
(8) ** Studies to relate amount and type of asbestos in the lung and estimates of past dust exposure and interval since last exposure.
(d) assessment of the specificity cf small irregular (9) Experimental and epidemiological studies to
opacities in the chest radiograph as defined in investigate possible differences of eifect of continuous
ILO U/C Classification, 1971,
low and intermittent high exposure to asbestos.
(e) tests of the usefulness of different tech (10) Opportunities afforded by intercurrent deaths
niques of chest radiography, including the use of should be used to interrelate radiographic appearan
100 mm films,
ces, lung pathology, respiratory function, and dust
( f) development of statistical procedures for content and type in asbestos workers. Standardized
analysis and presentation of serial observations, techniques and classification recommended by rhe
(2) * Evaluation of the usefulness of early detection panels should be used.
in the prevention of progressive fibrosis a.id asbestos (11) Investigation of the prognostic significance and
cancers, also in the identification of hazardous aetiological factors in the development of calcified conditions. Routine health surveillance cf industrial and uncalcified pleural plaques in different environ
populations should be designed to assist epidemio logical studies and should include measurement and recording of environmental dust levels. Surveillance of new entrants could be particularly valuable. Arrangements should be made to register workers so that their morbidity and mortality experience can be studied even after cessation of exposure to asbes
tos.
ments.
(12) Investigation of talc-exposed groups in mining and manufacturing to establish any dif ferences in morbidity or mortality which might be related to the amount and shape of the fine respirable particles. (13) Development of cost 'benefit analyses to study the health, safety, social, and economic interrelations
(3) * Assessment of excess cancer risks following of the use of asbestos. exposure to only one type of fibre:
(o'! Chrysotiic The much higher cancer risk reported for chrysotile textile workers compared
Pathology and experimental pathology
with mine and null workers requires explanation. How much is explicable by deferences in size of airborne fibres and past dustiness? Theie is need to make more use of past dust records for relating to
The panel reviewed the progress made on the 1964
L'ICC recommendations. It was agreed that con siderable progress had been made on the majority of tiic recommendations. Some require further study,
indices of disease.
or modification of prev ious methods of i:i\estimation;
(/) A.wv.'te The excess lung carcinoma and ihcxe are included in the list of recommendations
mesothelioma risk is apparently ranch greater in the that follows. The recommendations are divided into
Report o f the Advisory Committee on Asbestos Cancers 183
three categories; morbid anatomy and histology, Clinical research
clinical research, and experimental studies.
(1) *` Monitoring by immunological methods of
populations exposed to asbestos should fc-e in
Morbid anatomy and histology
vestigated to ascertain whether it is possible to
Projects
recognize those who arc developing, or will develop,
1. Asbestosis
tumours.
(1) * Further consideration should be given to (2) The use of chromatographic methods for the
methods for determining the amounts, types, and study of mucopolysaccharides and other turr.our-
structural features of asbestos in tissue. A sub asvoctated substances in pleural fluids should be
committee should be established with members of explored. Sensitive methods might be developed and
the Physics and Chemistry Panel and others to applied to identify secretory products of meso
accelerate work on this problem.
theliomas in blood and urine.
(2) The. methods for assessing the severity of
asbestosis should be tested for consistency by Experimental studies
different observers.
(1)* Information is required about the role of fine
2. Carcinoma
(IP* An investigation of whether reduction of
asbestos exposure to lexels below those producing
asbestosis also abolishes excess risk of carcinoma
was considered important.
(2) A comparison of lung carcinomas in persons
occupationally exposed to asbestos and those not so
exposed, including both cigarette smokers and non
smokers, in respect of sites of origin and cytology of
tumours a nd presence or absence of asbestosis, would
be of value.
3. Mesothelioma
*
(1) The International Panel of Pathologists1 andNational Panels established following the 1964
meeting2 have served a useful purpose. It is recom
mended that panels be established in other countries
and membership of the International Panel be extended. The main purpose of these panels is to
ensure uniformity of diagnostic criteria and recording
of histological types of diffuse mesothelioma. Col laborative study of histology slides in National
Panels is recommended. The diagnosis of meso
thelioma can be made by exfoliative cytology of the
pleural fluid. If the cy toiogieal diagnosis is made by a
competent cytologist, biopsy may be unnecessary.
(2) To improve consistency of diagnosis there is an
urgent need for a comprehensive atlas on mesothe
liomas or, alternatively, for inclusion of an enlarged
section on mesotheliomas in the new edition of the
WHO Monograph on Tumours of the Lung. Criteria for diagnosis by exfoliative cvtology and a
description of the tine structure of mesotheliomas
should be included.
particles, especially the influence of fibre size, in the induction of tumours. These studies should be extended to include fibres other than asbestos. A sub-committee should be established to review the need for, and arrange the distribution of, standard samples of asbestos and other fibres in addition to the L'ICC reference samples. (2E The fate of inhaled particles of various sizes, shapes, and chemical compositions should be studied to determine more precisely the quantities and sites of initial deposition, change within the body, and later retention. The feasibility of increasing fibre elimination by various methods should be explored. Studies should be made of means of reducing the fibrogenicity and carcinogenicity of fibres already retained in the lungs.
(3) The use of ceil and organ culture, including mesothelial tissue from man and other species, should be further investigated vvith a view to develop ing methods of screening dusts for fibrogenic and carcinogenic properties. (4) Furiher studies should be carried out to determine the nature of the combined effect of tumour induction when animals are exposed to asbestos dust and cigarette smoke, metais or other chemical carcinogens, including those which act svstemically, such as nitrosamines.
(5) Inhalation experiments should be extended to test various types of fibre; of special interest are forms of ehrysotile and crocidolitc, including the finer grade materials.
(6) It was felt that studies of the pathological effects of asbestos on species ether than rodents would be of value.
(7) The effect of long-term ingestion of fibres of
The Intel-national Panel consists of: Dr. M. Kannerstein (USA). Professor D. M aurer (Canada). Dr. L. Mcurman (Finland). Professor W T. E. M eCaueitey (E-reX Professor H. Otto (FRG ). Dr. H. Plamevdi (Netherlands!, Dr. E. Roitzseh (G D R ), Professor L. Santi IItaly X Professor I.
various sizes, shapes, and chemical compositions
should be studied.
'
(S) Effects of fibres and assvNriated metals on metab
olism of target organs should be investigated.
Webster (South Africa), and Dr. J. C, W agner (U K ) as
Secretary.
Physics and chemistry
Great Britain. South Africa. United Slates. Canada.
Netherlands.
The panel reviewed the progress made on the 1964
184 Report o f the Advisory Committee on Asbestos Cancers
UICC Recommendations. The proposals for the preparation and characterization of the UICC reference samples of asbestos had been satisfactorily .implemented, and the panel recommended that a list of references to papers featuring tr.e samp'es should be distributed to investigators in this field. Considerable progress had been made on methods of identifying the type of fibre in tissues but a quan titative method when se'.eral types of fibres were present had yet to be developed.
The panel discussed the further contribution that physical and chemical studies can make to research c>n the biological effects of asbestos and other fibrous-material*.. Oi especial interest are tr.e effects o f fibre size and shape on the retention of material in the lungs, the site of deposition, the m-gration of fibres within the body, and their carcinogenic or other biological activity'. The following recom mendations were madet
Projects I. Materials for experimental work*f
(e) Supplies of asbestos from relevant sources should be obtained where there is evidence of varia tion in geological form, trace element content or significant biological findings.
(b) Small samples of various fibrous materials should be prepared for studies on the influence of fibre size and shape on carcinogenicity. For this purpose the samples should be milled to different degrees of fineness.
(c) For investigations on the influence of particle shape and size, on the inhalation and subsequent fate of asbestos fibres a chry sonic and an amphiboie o f fibre length greater than the UICC samples should be prepared.
2- Methods {a} There is an urgent need for the quantitative assessment, size analysis, and characterization of panicles and fibres in the lungs and other organs. Details of available methods should be circulated, international comparisons undertaken, methods standardized, and new techniques developed.
(b) No methods are at present available for the preparation of fibres in n a rro w ranges of diameter and length in sufficient quantities for inoculation experiments. Techniques for these purposes are urgently required, especially in view of me advantages such graded samples could provide for investigating the influence of these physical factors on the carcino genicity of fibres of different materials.
(c) Since the degree of dispersion of fibres (es pecially chrysotile) used in inoculation studies may
have a marked influence on their carcinogenicity, methods are required for quantifying dispersion. <d> inhalation studies require precise control of the characteristics of the dust clouds, improved methods of dispensing fibrous dusts in such investigations peed to be developed. (e> Methods are available for collecting the impor tant size fractions of dust clouds in inhalation studies when the particles are of compact shape. Similar methods must be developed for fibrous particles. (f ) The present membrane filter methods of measuring the levels of airberne asbestos dust require standardization. This should be done by interiaboratory trials on a continuing basis. Particle counting by electron microscopy should also be developed. Gravimetric assessment methods and the automation of particle counting should be explored.
3. Inhalation studies'" Considerable information is now- available on the deposition, retention, and migration of particles of compact shape. Recently developed methods, especially radioactive tracer techniques, should be used to obtain similar knowledge for fibrous par ticles. This information is needed to identify the biologicaliy important size fraction and to help inter pretation of epidemiological and pathological studies.
4. Occupational and em ironmental studies The use of both fibre counts and gravimetric methods for assessing asbestos dust concentrations should be encouraged. Data collected over an extended period will be particularly valuable in identifying the parameters of the dust which can be correlated with epidemiological evidence on the health hazard.
5. Physics and chemistry panel It is recommended that an international panel be established to assist in implementing these recom mendations. The panel would periodically review requirements for materials for experimental work, provide guidance on physical and chemical prob lems. and arrange national and international standardization trials.
References
IL O L' C In te rn a tio n a l C lassification o f R a d io g ra p h s o f Prciirnocoiuo-cs 1971. Occupational Safety and Health Scrxts. Inierrationa! l abour Of! ice. Geneva. 1972.
R eport and Rceor.imonJ.U'ons of the W orking G roup on Asbestos and Cancer convened under the auspices ol'the Geographical Pathology Co nniutco ol the Ir.ternaiional b n:on against C -ncer ib'IC C l (1Q6>1. Draisk Journal o f IttAxsrrtal , \ f 22, 165-171.
Report o f the Achisory Committee on Asbesto* Cancers 185
Dr. M. Bccklake Dr. H. Bohlig Dr. N. Day Professor P. C. Eirr.cs
Dr. J. C. Gilson D. J. Lcpoutre Professor J. C. McDonald Mr. C. E. Rossiter Dr. H. Sakabe Dr. I. J. Selilcoff1 Dr. G. K. Sluis-Cremer Dr. W. Smithcr Dr. G. Wright
Dr. A. C. Allison
Mr. G. Berry
.
Dr. P. Bogovski
Dr. M. Kannerstesn
Professor W. T. E. McCaughey Professor D Magncr
Professor H. Otto
Dr. H. T. Planteydt
Dr. M. Stanton
Dr. J. C. Wagner
Professor S. Watanabe
Professor I. Webster
Dr. L, Le Bouffant Mr. G. W. Gibbs Dr. S. Holmes
Epidemiology panel
McGill Universi'/. Department of Epidemiology and Health, 3775 University Street, Mentre:.! 110, Quebec, Canada Municipal He p::. 1Luj-.nsckeiJ. iw I.LdenscT.cid, Germany International Agency for kcscurJr on Cancer. Uni: of Epidemiology and Bicstatistics, 150 Co.irs Albert "fnomai, Lyon 6'J<, France Queen's Lni.cr:':;. cf Be.fast. Department of Therapeutics and Pharmacology, Institute of Ciir.cal Sc.er.ce, Gro>>cnor Road, Belfast BT12 6BJ, Northern
Ireland, UK Medical Research Council, Pneumoconiosis Unit, Llandough Hospital, Penarth, Glamorgan, Wales. UK fChairman; S-A. Eternit, Mcd.cal Department. 2920 Kapeile-op-dcn-Bo-,, Belgium McGill University, Department of Epidemiology and Health, 3775 University Street, Mermen! ! 10. Oi eb-ec. Car.eda Medical Research Council, Pneumoconiosis Unit, Llandough Hospital, Penarth, Glamorgan, V-aQs, UK Ministry of Labour, Department of Industrial Physiology, National Institute of Industrial Health, 2051 Kizukisumiycsricho, Kawasaki, Japan Mount Stnai School of Medicine. Environmental Sciences Laboratory, 100:h Street ar.d Fifth Avenue. New York, NY 1C029, USA South African Medical Research Council, National Research Institute of Occupational Diseases, PO Box 4758. Johannesburg, South Africa British Asbestos Research Council, J14 Park Street, London W1 Y4AB, England,
UK Department of Medical Research, St Luke's Hospital, 11311 Shaker Boulevard, Cleveland, Ohio 44101, USA
Pathology panel
Medical Research. Council, Clinical Research Centre, Watford Road, Harrow,
Middlesex HAI 3UJ, England, UK
Medical Research Council, Pneumoconiosis Lrnit, Llandough Hospital, Penarth,
Glamorgan, Wales, UK
International Agency for P.csearch on Cancer, Unit of Environmental Carcino
gens, 150 Cours Albert Thomas, Lyon 69305, France
Barnert Memorial Hospital Centre, Pathology Department, 6S0 Broadway,
Paterson, NJ 07514, LSA
Trinity College School of Pathology, University of Dublin, Dublin 2, Eire
Canadian Tumo-r Reference Centie, Department of Pathology, University of
Otlaua. Ottawa. Ontatio. KIN 6N5, Canada
Dircktor des patrolcgiscren Instituts der Stadt Krankcnanstalten, Beurhaus-
strasse 40, 46 Dcnmund. West Germany
Stichting Strccklaboratorium "Zeeland", Noorpoortplein 2, Middleburg, The
Netherlands
National Institute of Health, Department of Health, Education and Welfare,
Bethesda. Md, 20014. LSA
Medical Research Council. Pneumoconiosis Unit, Llandough Hospital, Penarth,
Glamorgan, Wales. UK (Chairman)
-
National Cancer Centre. Research Institute, Department of Pathology, Tsukiji,
5-1-1 Chorrte, Chuo-ku. Tokyo, Japan
Medical Research Council South Africa. National Research Institute for Occupa
tional Diseases, PO Box 47S5, Johannesburg, South Africa
Physics and chemistry panel
Centre d'Etudes et de Reeherches des Charbonnages de France, Verneuil-en-
Hallattc. B.P. No 27. 60550 Creil, France McGill University, Department of Epidemiology and Health, 3775 University Street, Montreal 110, Quebec. Canada Asbestoses Research Council, c o Turner Bros, Asbestos Co. Ltd., PO Box 40,
Rochdale. England, UK
'Unable to attend. 4-
1&6 Report o f the Advisory Committee on Asbestos Cancers
Mr. A. Morgan Dr. F. D. Pooley Dr. S. Sped Dr. V. Timbrell Dr. R. S. J. du Toit Mr. W. H. Walton
Atomic Energy Research Establishm ent, H ealth Physics and M edical Division,
Building 364. Harwell, D idcot. Berits, England, U K
University College of South Wales and Monmoutr.snire, Department of Mineral Exploitation, Newport Road. Card::!, Wales, UK Johns-Man. ii.'e Research and Engineering Center, Greenwood Piaza, Denver, Colorado, USA Medical P.esearch Council, Pneumoconiosis Unit, Llandough Hospital, Penarth, Glamorgan, Wales, UK
Government Mining Engineer's Division, Department of Mines, PO Box 1132, Johannesburg. South Africa
Institute of Occupational Medicine, Roxburgh Place, Edinburgh EH8 9SU, Scotland, UK (Chairman)
. The January (1973) issue
Morbidity of British coal miners in 1961-62 F. D. K. Liddell
Mortality of British coal miners in 1961 F. D. K. Liddell
A study of the acute and chronic changes in ventilatory capacity of workers in Lancashire cotton mills G. B e r r y , C. B. M c K e r r o w , M. K. B. M o l y n e u x , C. E. R o ssit e r , a n d J. B. L. T o m bleson
Use of radioisotopes in the study of textile workers with byssinosis and chronic lung damage L. S. V askov
A survey of respiratory disease in cotton operatives. Part I. Symptoms and ventilation test results A. J. Fox, J. B. L. T o m b l e so n , A . SVa t t , a n d A . G. W il k ie
A survey of respiratory disease in cotton operatives. Part IL Symptoms, dust estimations, and the efTect of smoking habit A. J. Fox, J. B. L. T o m bleso n , A. W a t t , a n d A. G. W il k ie
Computer simulation of industrial hazards E. G. Knox
Relationship between sickness absence and length of service S. J. Pocock
Radiological changes in carpal and meracarpal bones and phalanges caused by chain saw vibration T. K u m ijn ,
M. W llKERI, AND P, SMARI
Effect of silica on phospholipids in the rat lung M. G r n s p a n , H. A n t w e il e r , a n d W. D eh n en
Industrial ammonia gassing M. Walton
Notes and miscellanea
.
Safety and health at work: The Roberts Report R. C. B r o w n e
Employment Medical Advisory Service M a r g a r et G ra cey
Book review's
Inforntation section
'
A number of copies arc still available and may be obtained from the Publishing Manager, British Medical Association, Tavistock Square, London WC1H 9JR, price 125 <1-50 in countries overseas; U.S.A. $3.60).