Document DvdkJxvwRb51Me1DNXoQnVVnO

2nd Quarter, 1986 International Bulletin Published by The Asbestos Institute Vol. 1, No 4 The World Asbestos-Cement Industry: Moving Forward The First International Con ference on Asbestos- Cement highlighted the dynamism of an industry which is successfully meet ing the challenges of tech nological innovation and new market demands. ome 260 industrialists, re Ssearchers, architects, produc ers and public works officials from 45 c^y4,r*ries met May 4 to 7 in --"Cannes, France, for the First Inter national Conference on AsbestosCement w/iprp tb*y r=>\/r*werl fh*=* latest developments and new applications of asbestos-cement products, as well as recent techno logical innovations aimed at im proving the performance and properties of this material. The technical program consisted of six plenary sessions. A total of 34 experts from 19 different countries delivered papers on topics ranging from installation, new applications and material properties to the socio-economic impact of manu facturing asbestos-cement prod ucts. A Well-Adapted Material "This conference will have fur nished proof/' said Alain de Metz, vice-chairman of the Syndicat des Industries Frangaises du FibreCiment, "that, asbestos-cement has perfectly adapted itself to recent trends, which see every country, on the basis of its needs, searchingfor the material that best satisfies its concerns for economy, aesthetics, durability, ease of application and quality." aimed at promoting the worldwide exchange of information and transfer of technologies related to asbestos, and especially asbestoscement. The Industry's Dynamism and Vigour "The interest that this conference generated among the world asbes tos-cement industry," said Gary Nash, president of the Asbestos Institute, "the number of partici pants who came from around the world and the quality and diversity of the papers presented make us realize that such an initiative was long overdue. The conference, moreover, provided an opportun ity to confirm the vigour and dyn amism of the asbestos-cement industry, which is very active in the field of research and innovation and which has an outstanding potential for growth in many parts of the world." The Cannes sessions showed that' asbestos-cement is a material that is evolving in terms of its form, composition and applications in order to adapt to new conditions for its use as well as to the demands of both the market and general public for economy and safety. The conference also' confirmed the importance of the industry's role and asbestos-cement products in developing countries. Sponsored by the Asbestos Insti tute in cooperation with the Asso ciation Frangarse deTAmiante, the Canadian Centre for Mineral and Energy Technology and the Centre de recherches mineraies du Que bec, this first conference was so successful that many participants expressed the desire that it should be-the first of a series of meetings The Scientific Community Severely Judges the EPA Document See pages 2, 3, 4 and 5 Major Role in the Third World The internatic/nal panel focusing on socio-economic questions, which brought together represen tatives from China, India, Mexico, Senegal and the Philippines, high lighted the place and value of the asbestos-cement industry in the national economies of Third-World nations. The international panel indeed illustrated the enormous needs of Africa, Asia and Latin America for a material such as asbestos-cement in order to solve problems with housing, the transportation of drinking water, irrigation and drainage, as well as for the con struction of adequate sewage sys tems and other infrastructures. As one participant put it: "While in some quarters the controversy over asbestos has a tendency to drag on endlessly, asbetos, as the Cannes conference showed, con tinues in all four corners of the globe to be a force for social pro gress and a vehicle for economic development." HWBUI0001398 SCIENTIFIC EV ALUATION OF THE EPA PROPOSAL The Scientific Community Severely Judges the EPA Document group of international experts A has judged rather severely the scientific reasoning set forth by the U.S. Environmental Protection Agency (EPA) to justify its proposal to ban asbestos in the United States. Seemingly, the Agency has based its recommendation on data of often doubtful quality, on a model of analysis which is rejected by part of the scientific community and on incomplete documen tation. These conclusions can be derived from independent assessment re ports prepared by experts from Canada, the United States, France and Great Britain. Among the authors are several scientists re nowned for the studies they have published on asbestos over the Drs. }.M. G. Davis, ). Dunnigan, A. Langer and R. Begin at the information briefing on the EPA proposal. One of the scientists who attended often and thoroughly for its effect The Dangers of Substitution past 20 years. These specialists the briefing. Professor Arthur M. on humans suggests to the reader The EPA proposal to systematically agreed to convey their observa Langer, Associate Director of the that these data are unassailable. replace asbestos with various sub tions to the Asbestos Institute Environmental Sciences Laboratory This is simply not the case." stitute products is unanimously cri which made these public recently, of the Mount Sinai Medical Cen Dr. John C. Gilson believes that ticized by the experts consulted. - in Montreal, during an informa tion briefing attended by some of li namr-------------------------------- ---- ----------........ Questionable Scientific Basis ter, appropriately summed up the feelings,of,the experts consulted when- hgl'gxptamgcl "ttre circum- stances that led him to comment on the EP& proposal: "When one "the EPA has not made a convincing case for banning all asbestos". ~Fi na11 y, professor Patrick Seibas tie n agrees with virtually all of the spe cialists consulted, who have For example. Professor Siemiatycki foalc tbMJao4hDory that tubilffuto products would pose less risk than asbestos "may not stand up to scrut The experts showed an unusual generates data base and claims to iny'. Professor Siemiatycky points pointed out that the report of the unanimity in their conclusions, es have hard numbers to support this, out that "studies of workers ex American agency contradicts the pecially on two major points. All questionned some elements of the if those hard numbers are based on assumptions or guesses and on a majority of the most extensive stu dies carried out on this subject posed to man-made mineral fibres in the U.S. and in Europe may be scientific basis used by the EPA, framework that is not scientific, interpreted as showing risks of around the world. He deplores the particularly the fact that the Agency assessed all fibres equally, then, as a scientist, I must respond to it." fact that the scientific references in th document "come from obs lung cancer comparable to those seen with asbestos". without distinction between type or biological effects. All are also Major Deficiencies cure studies". Dr. Raymond Begin points out that the biological effects of the substi worried about the risk related to Most of the experts consider that Different Types of Asbestos tutes proposed by the EPA have the uncontrolled use of substitutes the report of the American agency In their evaluation of the EPA not yet been adequately evaluated which would hot have been sub contains major deficiencies from report, the experts are unanimous and that "several of these materials jected to the same tests and stand both the scientific and methodo in criticizing the EPA for not mak may well be at least as biologically ards as asbestos. logical viewpoints. ing a distinction between the var active as asbestos". ASBESTOS, April/May/June 1986. A publication of The Asbestos Institute, 1110 Sherbrooke St. West, Montreal. Quebec. Canada H3A 2M8, (514) 844-3956 Editorial Board: The Asbestos Institute and lntrcommunica Inc. Printing: Interlitho Inc. Legal Deposit: Bibliolheque Naliunaie du Quebec and National Library of Canada, Second Quarrer 1986. Vol. 1. No. 4. The articles appearing in ASBESTOS do not involve liability on the part of the govern ments which participate in the financing of The Asbestos Institute, or of the companies or unions represented on the Institute's Board of Directors. Their publication does not imply that the government, companies and union in question necessarily adhere to the opinions expressed therein. This publication appears in French, English and Spanish. Thus, Professor Alain-Jacques Valleron and Dr. Guy Thomas say that the EPA report does not meet any of the universally recognized scientific standards and that "using the conclusions of this type of report for regulation purposes would seem to be abusive". For his part. Professor Jack Siemiatycki asserts that "the estimate of risk by the EPA is based on crude guestimates". In this light, the Montreal epidemiologist feels that "the proposed ban on asbestos would be something of an expen sive gamble". Professor Arthur M. Langer points out that the environmental data used to support the Agency's posi tion "are not that good". Notes Dr. Langer: "The statement that asbestos has been studied most ious types of asbestos. For Dr. J.M.G. Davis, this approach "ignores a vast amount of epide miological evidence that chrysotile is a much safer material than the amphiboles". Professor Langer, who also dis agrees with the EPA's attempt to group all types of asbestos together, believes that "chrysotile asbestos should be permitted in the manufacture of vinyl-asbestos tiles,friction productsand asbestoscement pipe". The New York scientist, who emphasizes that the use of chrysotile asbestos must be subject to rigorous controls in the work environment, is nonetheless in favour of banning crocidolite and amosite. According to Dr. Davis, "present knowledge suggests that any fibrous product that has fibres of the same dimensions as asbestos and the same fibre durability in lung tissue will be equally hazar dous". Potentially Carcinogenic Products Professor Langer, who has ana lyzed the preliminary tests carried out on a half-dozen products pro posed as replacements for asbes tos, points out that these tests have shown that the products in ques tion are potentially carcinogenic. Professor Sebastien believes that "it is unwise in terms of public health to propose several mineral fibres to replace asbestos in its mul tiple uses. In fact, that would only compound a variety of uses with a HWBUI0001399 SCIENTIFIC EVALUATION OF THE EPA PROPOSAL A Proposal That Should Be Drastically Amended -- Dr. Arthur M. Langer variety of pollutants, making the situation even more difficult to control, both on the level of indus trial hygiene and of the environ ment". Because of the many uncertainties involved in the use of substitute products, the experts recommend that these products be subject to regulations and standards that are as strict as those imposed on asbestos. A Questionable Cost/Benefit Ratio Although not all of the experts touched on the EPA's analysis of the cost/benefit ratio in banning asbestos, those who have exam ined it generally tend to question its validity. Dr. Gilson feels that the EPA has not provided sufficient information to establish the cost elements: "The EPA give us no information on the reliance to be ^jpjaced on the cost figures." For his part. Professor Siemiatycki feels that the price the Agencywants the American public to pay is disproportionate to the results it hopes to achieve: "From a public health viewpoint, more lives and years might be saved by investing in anti-smoking campaigns, anti alcohol campaigns, transportation safety or other public measures." rofessor Arthur M. Langer In the case of friction products, the Papproves of the EPA's goal. He American researcher recommends is asking the Agency, however, tothat the use of chrysotile continue drastically amend its regulatory to be authorized. He notes that it proposal to allow for the controlled would take several years before use of chrysotile asbestos. substitute products could be ade The New York researcher starts off quately tested. by saying that a total ban on asbes Professor Langer proposes the tos cannot be logically justified establishment of a special inter solely on the basis of an assessment agency committee to regulate the of the risks this product poses to use of all inorganic fibres. He the health of the general public. underlines that certain mineral He explains that the data from fibres, whether natural or syn which the risk can be extrapolated thetic, create problems similar to to the population as a whole is too asbestos and should be regulated scanty to arrive at precise, numeri in the same way. The author men cal conclusions. Professor Langer tions half a dozen substitutes which asks the EPA to stop evaluating the studies have shown can be carci number of deaths that might be nogenic. caused by asbestos. A Social Problem Keep Chrysotile for Specific Uses The New York researcher severely Professor Langer formulates sev eral specific recommendations in criticizes the studies which the American agency uses as the basis cluding banning crocidolite and amosite as quickly as possible. On for its statement that short expo sures to asbestos fibres can percep the other hand, he recommends that chrysotile continue to be used tibly increase the risk of cancer. He also rejects the notion, put forth by in the manufacture of vinyl tiles the EPA, that many cases of meso and asbestos-ciment pipes. He thelioma can be linked to the pres states that there is no solid evi ence of asbestos in the environ dence leading to the conclusion ment. He thinks that these cancer that these products are hazardous cases are more likely related to the to health. workplace. In concluding. Professor Lanj considers it socially prudent reduce the public's exposure asbestos fibres. In this regard asks: "Can a resolution achieved to protect the gene population and still use asbes "safely"? I think yes. By elimi tion of amphibole asbestos, b ning of cigarette smoking specified buildings, structures ; workplaces, workplace cont and work practices, and use of ; substitutes, this can be achieved. Dr. Arthur M. Langer Associate Professor and Associate Director, Environmental Sciences Laboratory, Mount Sinai Medical Center, New York, U.S.A. Controlled Use of Asbestos Along with many of his colleagues, Professor Langer rejects the notion of banning asbestos as proposed by the EPA: "Can a resolution be achieved to protect the general population and still use asbestos safely? I think yes. By elimination of amphibole asbestos, banning of cigarette smoking in specified buildings, structures and workpla ces, workplace controls and work practices, and use of safe substi tutes, this can be achieved." Dr. Robert Murray finds that the EPA proposal is an unjustified action "which borders on almost obsessive paranoia". Noting that society has learned how to control many dangerous industrial sub stances such as phosphorous and carbon bisulphite without having to ban them. Dr. Murray suggests adopting a similar approach to asbestos, "whose risks can be con trolled". Weak Cost/Benefit Analysis -- Dr. John C. Gilson Dr. John C. Gilson believes that the cost/ben^fit analysis on economical means of reducing the number of cancer cases. which the EPA bases its recomOn this point, he writes: "If the mended ban on asbestos lays itself proposed ban on asbestos went wide open to criticism. He particu into effect today, there would be larly deplores the lack of a detailed no impact on the number of deaths breakdown of the two billion dol caused by asbestos until the year lar figure cited by the Agency. 2000. And it is difficult to assess, for The British physician also notes cancers occurring after the year that if substitutes prove less effec 2000. what proportion can be tive than asbestos, they may cause deaths whose cost has not been linked to exposure prior to the ban." estimated by the American agency. He mentions three types of uses for which this calculation should have been made: fireproof construc tion materials, asbestos friction materials and asbestos clothing. Uncertain Benefits Dr. Gilson questions the logic of banning asbestos and asks whether a ban is the most effective and Dr. Gilson, in fact, believes that it is difficult todeterminewhatproportion of cancers can be avoided in the workplace and environment by banning asbestos. Methodological Flaws In addition, the British researcher sees several methodological errors in the EPA's analysis. He notes first that the Agency makes no disti tion between the various type: fibre, which runs counter to most recent research on the hai ful effects of asbestos. Dr. Gilson also points out that ing to predict the number of po ble cancers using the number fibres inhaled per year as the s criterion is a delicate matter, points out that this would reqi combining several variables si as the dimensions of the fib their distribution in the air, tf degree of aggregation, the typ< fibres and maybe even the parti lar blend of different types fibres. Dr. Gilson concludes that the I has not assembled a convinc case for banningail forms of ast tos. Dr. John C. Giison Former Director of the Medical. Research Council, Pneumoconiosi Unit, Penarth, United Kingdom. HWBUI0001400 SCIENTIFIC EVALUATION OF 1 HE EPA PROPOSAL A Document Lacking in Accuracy and Perception -- Dr. J.M.G. Davis r. J.M.G. Davis believes that The British physician is equally Dthe EPA's calculations are fre surprised that the American agency quently based on studies which aarelso draws no distinction between not accurate enough to justify fibres of different dimensions. He banning asbestos. He especially points out that current studies denounces the use which is made indicate that long and thin fibres of data collected before 1960. are much more carcinogenic than The British physician explains that short and thick ones. the techniques available at the As for substitute products, Dr. time did not permit an accurate Davis notes that any product con count of the number of airborne taining fibres with the same dimen dust particles. At best, one could sions as asbestos and the same define three levels of exposure: durability in lung tissue are just as high, medium and low. Dr. Davis hazardous. He states the problem believes that, given these condi in these terms : "Doesan industrial tions, one cannot determine the society need products made of fine health risk, the way the EPA does, and durable fibres? If so, then with very much precision. fibres with a high degree of dura Dr. Davis also notes that the linear non-threshold dose/response model which the EPA used is far from gaining the unanimous approval of the scientific commu bility in the environment and little durability in lung tissue would be the ideal material. In that case, it may prove difficult to find one bet ter than chrysotiie." nity. The main problem, according to him, stems from the lack of data on exposure to extremely low doses so that one must content oneself with extrapolations such as those which the EPA employs. Under these conditions. Dr. Davis thinks that the model used may over-estimate the risk of cancer from exposure to carcinogens. Chrysotiie and Substitution Products Dr. Davis is also very surprised that the EPA makes no distinction be tween chrysotiie and other asbestos fibres. In hisview, this attitude runs counter to several epidemiological studies which show that chrysotiie is much safer than other types of fibre. Dr. J.M.G. Davis Head of the Pathology Unit, Institute of Occupational Medicine, Edin burgh. United Kingdom. the diversity of pollutants and make the situation even more dif ficult to control. A Lack of Scientific Rigor In addition to this basic criticism. Professor Sebastien thinks that the American agency argues its case with a great deal of clumsiness. He accuses it of frequently basing its recommendations on obscure scientific references. Also open to criticism, according to him, are the basicdata on pollution levels in the environment, which were obtained by different methods. He main tains that some techniques of measuring fibres in the air were even abused. Mr. Sebastien states that "such practices are morally questionable, contribute nothing to science, and offer no solutions to social problems". Professor Sebastien concludes: "It is understandable that an agency such as the EPA should propose a ban on asbestos, even if it argues its case clumsily. However, the agency can be criticized for recommending that asbestos be replaced by several man-made mineral fibres." Dr. Patrick Sebastien Professor, School of Occupational Health, McGill University, Montreal, Canada. A Questionable Analytical Model -- Or. Jack Siemiatycki rofessor Jack Siemiatycki criti points out that American and Pcizes the mathematical model European studios of workers expo of the "linear non-threshold doses/ed to synthetic fibres show risks of response" type used by the EPA. lung cancer comparable to those He thinks that the American of asbestos. agency never proved that this was the most coherent model available. Professor Siemiatycki calculates that the price to be paid is dispro The Montreal researcher criticizes portionate with the results one the specific parameters of the could hope to obtain. "From the model selected because they are point of view of public health, it based on measurements con would be much more profitable to ducted among a single group of invest in anti-smoking and anti workers in the 1960s. Since the data drinking campaigns, in transporta used contain no individual mea tion safety and other community surements and are based on an health measures."* identical average exposure for all workers. Professor Siemiatycki concludes that the basic para meters of the model constitute only crude approximations. Morally Questionable Practices -- Dr. Patrick Sebastien Professor Patrick Sebastien deplores the EPA's scientific mals through inhalation. If the EPA wants to ban asbestos in the United clumsiness and rejects its proposalsStates, it should find technological for substitutes. solutions that do not involve other On this subject he writes that he mineral fibres". has "doubts about the harmless Moreover, the idea that several ness of substitute mineral fibres, new fibres could be called upon to especially rock wool, for which there is epidemiological evidence replace asbestos strikes this French specialist, currently working in of carcinogenic action, and Montreal, as a lack of wisdom. He ceramic fibres, which have pro believes that multiplying the sub duced cancers in laboratory ani- stitute products would only add to Moreover, the researcher thinks that the fact of selecting a single model and a single study seems to give the EPA estimates a degree of accuracy which* they do not deserve. According to him, a cred ible model would express the cal culations of risk in terms of orders of magnitude. The Risks of Synthetic Fibres Professor Siemiatycki blames the EPA forconsrderirrg that all types of asbestos are equally harmful. He also feels that banning asbestos would be a costly speculation. He thinks that the thesis stating that substitute products are less hazar dous would not stand up to an indepth study. On this matter, he Dr. tack Siemiatycki Professor, Epidemiology and Preven tive Medecine Research Center, fnstituf Armand-Frappier, Montreal, Canada. 4 HWBUI0001401 SCIENTIFIC EVALUATION OF THE EPA PROPOSAL Using Such a Report for Regulation Seems Abusive -- Dr. Alain-Jacques Valleron and Dr. Guy Thomas rofessor Alain-Jacques Valleron lated on the basis of insufficient Pand Dr. Guy Thomas criticize data and crudely estimated. An the EPA study for breaking univero ther of their criticisms is that the sally-recognized scientific rules. American analysis does not take After an assessment of the method the physical characteristics of fibres ology used by the American into account. They also fear that agency, they conclude that using the models used and simplificative the conclusions of this kind of hypotheses which they contain can report for regulatory purposes sometimes be incompatible with seems abusive. the basic data available. Professor Valleron and Dr. Thomas challenge the estimated cost of substituting new materials for asbestos as arrived at by the EPA. They specifically note the fact that the health risks of substitute prod ucts are not taken into account. The French researchers also take issue with the EPA's evaluation of the benefits for public health that could result from a ban on asbestos. Professor Valleron and Dr. Thomas conclude: "The major deficiencies of the EPA report are its complete failure to discuss the results in terms of their uncertain nature and its failure to synthesize published works." A Questionable Theoretical Model Dr. Begin also questions the theo retical model which the EPA used for its analyses. It strikes him as par ticularly inadmissible that this model has no threshold. The fact that many workers exposed to asbestos have never contracted illnesses related to exposure to asbestos dust seems to prove, he says, the existence of definite thres holds in the development of asbestosis. He also challenges the linearity of the model used, on the basis of recent studies which indicate that exposure to low doses of chrysolite results in no excessive incidence of lung disease. Dr. Begin therefore thinks it unfair that a regulation aimed at banning asbestos should be based on that type of model. The Sherbrooke physician also questions the safety of the substi tute products which the EPA pro poses. He says that the biological activity of these substitutes has not yet been sufficiently assessed and that some appear to be just as harmful as asbestos. Dr. Begin therefore recommends that all fibrous materials be subject to the same regulatory control as asbestos and that the labelling requirements for all fibrous mate rials be similar. Dr. Raymond Begin Head of the Chest Clinic, Sherbrooke University Hospital, Canada. An Uncertain Scientific Procedure They explain that the problem stems from a lack of uniformity in the methods used to collect data, with some old studies measuring solid airborne particles while more recent studies directly count the fibres. The authors think therefore that the results should be ex pressed in terms of order of magni tude or large confidence intervals rather than in precise figures. Professor Valleron and Dr. Thomas emphasize that the EPA's approach involves a number of scientific uncertainties. They especially chal lenge the parameters of the risk/ exposure equations used by the Agency because these are calcu- Dr. Alain-Jacques Valleron Professor of Biomathematics and of Biostatistics, Universite de Paris VII; Unit Director, National jpstitute for Health and Medical Research (INSERM), France. Dr. Guy Thomas Centre Anti-Poison, Hopital untversitaire Lariboisiere-St-Louis, Universite de Paris VII, France. Conclusions Based on Doubtful Assessments -- Dr. Raymond Begin r. Raymond Begin severly Dcriticizes the analytical that half of all cases have no con nection with asbestos. He further methods used by the EPA and dsispecifies that this pulmonary lesion agrees with the Agency's conclu occurs no more frequently in the sions, commenting especially on Eastern Townships asbestos mining the relationship between certain towns than in any large city. types of cancer and asbestos. The University of Sherbrooke pro In the case of pulmonary carci fessor also disagrees with the EPA's noma, Dr. Begin notes that cig conclusions on the risks related to arettes are by far the decisive factor brake maintenance and other and once this factor is eliminated, asbestos-based friction products. this type of cancer is rarely seen. As He says that there is only one study for mesothelioma. Dr. Begin points on the subject and the data which out that this disease is very rare and it contains are unconvincing. An Unwarranted Act and Flawed Arguments -- Dr. Robert Murray r. Robert Murray thinks that a risks can be controlled. As for the Dban on asbestos such as the threats posed by asbestos in build EPA proposes is an unwarranteindgs, the British expert says that he act that stems from an almost has not found a shred of evidence obsessive paranoia. He notes three in the EPA documents to allow that fla^vs in the American agency's danger to be scientifically defined. argument. Dr. Murray points out that man has First, according to Dr. Murray, learned to control a .number of comes the Agency's failure to hazardous industrial substances ignore the threats posed by other such as phosphorous or carbon mineral fibres mentioned as possi disulfide without having to ban ble substitutes for asbestos. He them. He recommends adopting maintains that these fibres, the same positive attitude towards whether natural or synthetic, are as asbestos. hazardous as asbestos. As a result, if regulations governing asbestos are to be adopted, he hopes that they will also extend to substitute fibres. A Defective Methodology The second flaw in the EPA study, according to Dr. Murray, is attrib uting instances of death to a sin gle cause : asbestos. He argues that the Agency systematically ignores other possible contributing factors and thinks that the importance placed in asbestos is out of proportion. Thirdly, Dr. Murray rejects the assertion that "a single fibre can be lethal". He notes that the risksarea function of the type of asbestos fibre and its physical dimensions. Moreover, he maintains that these Dr. Robert Murray Professor, London School of Hygiene and Tropical Medicine; President of the /nternat/ona/ Occupational Medi cine Association, London, United Kingdom. HWBUI0001402 LATIN AMERICA The Pan American Health Organization Rejec hanks tp the numerous inter of the asbestos mining and manu Tventions which were medically, facturing industry in the industrial scientifically and technically welilzed and developing countries of documented, the participants at a the American continent. The fol meeting held in Mexico City and lowing session focused on the organized by the Pan American health problems related to expo Health Organization (PAHO) sure at the workplace and in the adopted recommendations in fa environment. vour of thecontrolled use of asbes tos. This signalled a clear rejection of the original demands for ban ning advanced at the beginning of the meeting. This position was adopted at this important meeting of experts Lively Discussions Some of the presentations at this session, in particular those dealing with assessment of risks related to asbestos exposure, gave rise to lively discussions. sponsored by the PAHO, which is the regional office of the World Health Organization (WHO), in order to take a position on the health problems related to the production and use of asbestos in Latin America. The group of experts, whose recommendations have since been published, consisted of 24 partici pants and 35 observers, represent ing governments, university insti tutions, scientific organizations, industry and consumer organiza tions from nine countries of the American continent, as well as of representatives of international organizations. The meeting began with a survey Thus, Dr. J. Corbett McDonald, a well-known epidemiologist, and Dr. Jacques Dunnigan, research director of the Asbestos Institute, in particular challenged the alar mist predictions of Dr. William J. Nicholson of the Mount Sinai School of Medicine concerning asbestos-related cancer deaths in the United States. They pointed out that the figures had been con siderably reduced since 1978, when the Califano report predicted 64.000 deaths a year. The following year. Dr. Irving Selikoff brought the number down to 40,000 at the OSHA hearings, to lower it again to 10.000 in 1981, in a study made for the U.S. Department of Labor. Finally, in a study for the U.S. Con gress, Drs Richard Doll and Julian Peto estimated the number of asbestos-related deaths to be between 2,000 and 4,000 a year. Also refuted in Mexico were the statements of Dr. Arturo Lomeli, the representative of Latin Ameri can consumer associations, in which he claimed that lung cancer was the cause of death for 20% of asbestos workers. Appeal for Cooperation In the group's view, the control of the use of asbestos in Latin Amer ica should be based first of all on a more accurate assessment of the hazards involved, which would permit the implementation of a plan of action for risk reduction. From the discussions in Mexico City, it also appeared that only through concerted action would it be possible for all parties con cerned, namely the workers, in dustry and governments in each country, to introduce a policy for comprehensive monitoring of all asbetos use. It was also stressed that the coun tries which already have adequate regulations and technology should assist in improving the working conditions in the industrializing countries by way of training pro grammes on control techniques and industrial health as well as through transfer of technology. This type of cooperation, which should be coordinated by interna tional organizations such as the World Health Organization, the Pan American Health Organiza tion and the International Labour Office, would enable industry in the developing countries to im plement the recommendations adopted at the Mexico City meet ing and thus would promote a generalized control effort in the use of asbestos. Assistance by the Institute For its part, the Asbestos Institute has been invited to assist in the organization of training sessions in monitoring for industrial hygien ists and in the detection of health problems at the workplace fot physicians. The Institute also intends to make available to the governments con cerned the scientific and technica information required to establish control standards for the asbesto< industry. HWBUI0001403 LATIN AMERICA the Banning Approach Argentina and Brazil go lor Controlled Use =** Recommendations of `thfc 'Sfeeidy Group on "Asbestos and Health In. Latin America" he experts who participated in Workers handlmg asbestos are th#^ the- Mexico meeting feel that population group most > at iu>k* two Steps must be taken concurpriority must be given to lowering rently n order to deal with the the level of exposure of that group, problems posed by asbestos use and thereby reducing the rate of mor to propose measures to protect the bidity and resulting mortality. health of workers and the commu nity ar large: 1. Identification and evaluation of ?.. the hazards v 2. Control of the risk factors It is suggested that each country set . up its own plan of action which ; could be developed by multi-disci plinary groups consisting of representativesfrom government depart- Identification and Evaluation of the .Hazards ments (labour, environment, health, social welfare, etc.), indus try, unions, consumer associations . ,The data on hand are incomplete and scientific institutions. jind originate mainly from limited ^studies without any follow-up. Con- tquerrtly,rt ts necessary to insist on Such a plan of action should include: ^^development of systems for ** * ............................I observer oups' evfynse^d "to asbesroS a) Establishing asbestos exposf*r^&: Hitku and 9ampUng'4*M*d standards, with mpbasts on uni- ' in the workplace and elsewhere. To form sampling techniques and this end, it Is proposed to: methods of analysis. a) Create a register of ail companies involved In the mining and indus trial ..use of, asbestos, detailing the SIDDunt consumed and the type of Hfcpe used. |>}.'g9Sat>lish a program of regular fnelfical examinations of workers exposedto asbestos. Conduct studies of the working environments by using uniform sampling techniques and methods ot analysis. d) Study work practices and identify high-risk operations, b) Establishing standards with re- -v gards to asbestos imports, transport, manufacture, marketing and waste and to asbestos-containing prod--I ucts, with a view to lowering the hazards to workers and the popula-4 tion at large, and with emphasis on the use of the best industrial tech-V niques available. c) Formulating and implementing^ an educational program directed at s employers and workers on hazard'' prevention and control, hygiene and security at the workplace. e) Identify the industrial processes where asbestos could be replaced immediately by proven non-toxic substitutes as, for example, in the case of heat insulators and other products using loose fibre. 4} Evaluate the hazards to communi ties, particularly those situated close to companies which produce and/or use asbestos products or to asbestos waste dump sites. d) Disseminating to the community at large the existing scientific knowl edge on asbestos exposure hazards and the preventive measures. e) Searching for, developing and ! using asbestos substitutes which have been proven to be less toxic. f) Establishing a system for report ing and recording asbestos-related diseases. The launching of these activities will provide information which in turn will allow the development of effi cient hazard control programs. Controb of the Risk Factors Scientific-evidence suggests that ail control efforts must be geared ' towards reducing exposure to the ^lowest possible level. Control mea^ sures must be taken immediately in those areas where exposure to is known to exist. g) Establishing a system to inform workers on the results of their peri odic medical examinations. h) Strengthening the learning pro cess of medical students, at the graduate and post-graduate level, to enable them to diagnose asbestosrelated diseases. i) Improving the professional train ing, at the graduate and post graduate level, of engineers and industrial hygienists involved in the asbestos industry..!! t Igfellfo ___,mi _____ Asbestos-cement is a building material especially well suited to the needs and means of Latin American countries, from pipes of various sizes to individual pre fabricated dwellings such as the one shown here. Argentina he Argentinian authorities res to be enlightened on the approach Tponsible for Environment and advocated by the Commission of for Occupational Safety and Healththe European Communities. have agreed that it would be advis able for Argentina to have strict and efficient regulations for the controlled use of asbestos. Such was the conclusion reached by representatives of the Argenti nian administration at the end of a symposium on the most recent developments in the knowledge of asbestos-related risks. Held early this year in Buenos Aires at the initiative of the Asbestos Associa tion of Rio de la Plata, the sympo sium was held under the auspices of the National Administration for At the end of the symposium, which was also attended by doc tors, lawmakers, civil servants, industrialists and unionists from Paraguay, Uruguay and Brazil, the National Director of Occupational Safety and Health and the Director of Environment Quality of Argen tina concluded that their country should adopt "modern standards and a national program for the controlled use of asbestos, along the European pattern". Brazil Environment Quality, of the Foun "There is no question of the Brazil dation for Education, Science and government planning to ban asbes Culture and of the Argentinian tos products, which ranks among Society of Ecotoxicology. the most widely used construction The Argentinian authorities had invited international asbestos ex perts at this meeting, to review the materials throughout the Country, especially for asbestos-cement roofing and water reservoirs." dust measurement methods used That was how the director of in the workplace and in the envi Brazil's Federal Environment ronment, the most recent medical and scientific data on asbestos and the regulations and standards cur rently applied in European user Agency, Mr. Paulo Nogueira Netto, put it during the Sao Paulo Interna tional * Conference on "Asbestos Exposure in the Environment and countries, and more particularly in Workplace". Organized by Funda France. Centro, the Institute for Safety and The French experience with pollu tion prevention^ in the asbestos industry was a major focus of this meeting to which the Argentinians had invited a large delegation from Health in the Workplace attached to the Department of Labour, the conference last April brought together some 250asbestos experts from around the world. France. In light of the papers delivered. Concerned about the international controversy on asbestos and the Mr. Nogueira Netto launched an appeal to asbestos manufacturing contradictory answers it sometimes leads to, the organizers of the sym posium wanted to hear about the multidisciplinary approach adopt ed in France to ensure the con trolled use of asbestos, through companies, asking them to estab lish very strict controls, especially for ventilation and air filtration, so that asbestos could continue to be used without sacrificing worker safety. both regulation and the imple mentation of permanent consulta tion mechanisms between all parties involved. They also wanted 7 4 HWBUI0001404 LATIN AMERICA An Asbestos Mission Visits Eight Latin American Countries Canadian mission undertaken A on the initiative of the Asbes tos Institute has just completed its rourof eight Latin American coun tries. Its object was to emphasize the importance of the active col laboration of these countries in the development and implementation of standards which would allow the controlled use of asbestos. The mission included government representatives, advisors and tech nical experts of the Institute, as well as the director of the Associa tion Fran^aise de I'Amiante {French Asbestos Association) who joined the delegation in order to contrib ute to the viewpoint of asbestos users and to specify the orienta tions accepted by the European Community. Thanks to the good offices of the Canadian Embassies and Quebec Delegations, the mission had the opportunity to meet most of the government officials directly con cerned with issues relating to worker protection. Information and Pooling of Efforts The eight countries visited during the months of February and March, namely, Ecuador, Colombia, Vene zuela, Mexico, Brazil, Uruguay, Chile and Peru, welcomed the delegation with great interest. The mission prompted numerous re quests for information on available safety technology and on the research and technical assistance programs of the Institute. Discussions were initiated on the importance of setting up national associations of manufacturers of asbestos products, where they do not already exist. Such associations enable small companies in particu lar to have access to the tech nology of the larger industry at reduced cost. They also allow the pooling of efforts aimed at estab lishing and implementing safety standards in each country. The creation of national associa tions moreover facilitates the organization and follow-up of training and educational programs for personnel and gives more weight to representations made to individual governments. Finally, given the increasing international ization of all the issues relating to the health and safety of industrial activities, only structured national associations can ensure the affilia tion of members with international associations capable of lobbying 8 Asbestos-cement water reservoirs represent an important part of the production of Colombit, a company located in Manisales, Colombia, which was visited by the asbestos mission. efficiently both regulating agen cies and organizations as well as individual governments. A Useful and Economical Material The Canadian delegation had the opportunity to note that asbestosbased products, and more particulary building materials, meet per fectly some vital development re quirements of that geographic region while offering definite eco nomic advantages in comparison with other materials. The members of the delegation visited important asbestos-cement plants in Colombia, Mexico, Brazil and Peru. During these visits they found that the safety measures concerning asbestos dust are com parable to those in force in much more industrialized countries. The delegation also inquired about the working conditions prevailing in smaller production units of sundry materials (textiles, brake linings), about which there seems to be much less information available. It is indeed appropriate that the issue of asbestos be considered with equal efficiency at all levels. This is what the delegation pointed out to their counterparts while inviting them to call upon the Asbestos Institute and the Association Fran<?aise de I'Amiante for any matters dealing with workplace preven tion and controls. Reactions to the EPA Proposal Some concern was voiced to the delegation about the announce ment of the proposed by the EPA in the United States. However, the delegation had an opportunity to explain the context surrounding the steps taken by the EPA, which had already been rejected once in 1984, following strong international reaction. The^Latin American industrialists, who were largely unaware of the procedures which must be fol lowed in the United States with regard to any proposals concern ing regulation, were afraid of find ing themselves faced with a fait accompli. The negative publicity surrounding the EPA proposal has already affected certain deliveries and several orders for asbestos products destined for the United States have been cancelled. It certainly appears that the inform ation widely disseminated in the Latin American countries has been very incomplete and biased. Sev eral businessmen complained to members of the delegation that they had been flooded with un solicited material put out by U.S. and other companies manufactur ing asbestos substitutes who have taken it upon themselves to public ize the EPA proposal. Furthermore, this same approach seems to have been adopted by some American embassies and consulates which have been disseminating systemat ically, and for some time already, any negative information on asbestos. In all likelihood, such strategy is partly responsible for the many questions brought to the attention of the Canadian mission concern ing the possible use of substitute fibres and the work and research pursued by the Institute in this field. Interest In the Controlled Use Although the commotion caused by the EPA proposal has con tributed generally to greater inter est of governments and labour movements in the controlled use of asbestos, the degree of aware ness of the issue varies considera bly from one country to the other. Brazil, for example, has recently given clear priority to asbestos, as evidenced by the Sao Paulo con ference which took place at the end of April and brought together the leading international scientists in the field of asbestos-related health issues in the workplace and During the meetings with repre sentatives of governments, unions and industry, great interest was expressed in obtaining the co operation of the Institute for tech nical training programs aimed at ensuring the controlled use of asbestos. Moreover, as a result of this mission a closer collaboration with Canadian diplomats abroad has been established and this will ensure an efficient follow-up of the programs and actions under taken by the Institute in the course of the next few months. The visits of the asbestos mission were made by two distinct delega tions comprising the following members: Jean-Pierre ChevalierBultel, delegation head and direc tor of Latin American Relations, The Asbestos Institute; Dr. Michel Lesage, medical advisor, The As bestos Institute; Jacques Dunnigan, director general. Research and Development Division, The Asbestos Institute; Henry Martin, Task Force on Asbestos, Energy, Mines and Resources Canada; Denis Hamel, economist, Quebec Department of Energy and Resour ces; Jean-Yves Tremblay, director. Industrial Minerals Division, Ener gy, Mines and Resources Canada; Jacques Roberge, director, ParaDepartmental Affairs, Quebec Department of Labour, Manpower and Income Security. HWBUI0001405 MINING PRODUCTION Asbestos Production in 1985 estern World demand for all World Production of Asbestos Wgroups of asbestos fibres rose slightly in 1985. It went up to 1980 1.84 million tonnes from 1.78 mil IJRSS 2,000,000 lion in 1984, according to prelimi nary statistkrs published by Energy. Mines and Resources Canada. However, fibre shipments by Can adian producers dropped to 743,700 tonnes from 836,654tonnes Canada Zimbabwe South Africa China Brazil 1,323.053 250.900 277,734 131,700 170,403 in the previous year. These ship ments were valued at 352.3 million dollars, compared to 379.3 million dollars in 1984. Canadian mines last year supplied Italy United States Greece Other countries 157,794 80,079 -- 200,270 40% of Western World demand. World production 4.591,933 Until 1982, that percentage had ranged between 50 and 60%. This loss of market share by Canadian producers is due mainly to a decline in sales to the United The Trends in Demand States, more intense competition from some producers and the aggressive pricing policies of others. U.S. demand for asbestos fibre is at its lowest level since 1938. The 207.000 tonnes used in 1985 repre sent a mere 25% of the record con- According to rhe prelitntnary esti sumprion reached in 1973. mates, world production including American users imported 28% less the USSR totalled 4.1 million fibres in 1985 than in 1983. How tonnes, about the same as the year ever, analysts expect demand to before. Canada, with 743,700 begin climbing at a rate of 4.4% this tonnes of shipments remained the year and foresee this trend con world's leading exporter of asbes tinuing until 1990. Consumption tos fibres. thisyearis expected to total 230,000 While dropping in Canada and tonnes. South Africa, production increased Japan is the second largest custom in several other countries. The er, after the United States, of Can USSR boosted production by 50,000 adian asbestos producers, japan's tonnes, Zimbabwe by 15,000 imports in 1985 remained at 100,000 tonnes, Greece by 10.000 tonnes. tonnes valued at 46 million dollars. Eastern Bloc countries by 29,000 A year earlier, Canadian deliveries tonnes and various other produ to Japan totalled 101,000 tonnes cers by 142,000 tonnes. with a value of 46.3 million dollars. About 80% of Canadian shipments in 1985, or 608,000 tonnes, came Two thirds of sales to japan con sisted of fibres in groups 6 and 7. from Quebec mines. The estimated value of those deliveries was 224 million dollars. In 1984, Quebec Exports of Canadian fibre to Com mon Market countries dropped to 131.000 tonnes valued at 100.1 mil shipments totalled 691,000 tonnes valued at 279 million dollars. lion dollars from 154,000 tonnes worth 115.1 million dollars in 1984. The decline in Canadian asbestos deliveries stems mainly from an 11% drop in demand for the prod uct in the United States. Fibre consumption totalled 207,000 Two thirds of these deliveries con sisted of fibres in groups 4 and 5. Exports to developing nations remained at about the same level as in previous years. tonnes in 1985 compared to 226,000 tonnes the year before. Canadian exports to the United States totalled 133,000 tonnes valued at 53.7 million dollars as against 185,000 tonnes worth 77.1 million dollars in 1984. Two thirds of these exports consisted of fibres in groups 6 and 7. 1981 2,000,000 1,121,845 247,600 235,943 140,000 138,417 137,086 75,618 30 145,919 4,242,458 1982 2,000,000 834.249 194,400 211,860 140,000 144,832 116,410. 63,515 17,500 145,551 3,868,317 1983 2,200,000 857.404 153,000 221.000 160,000 149,612 139,000 69,900 32,000 108,132 4,090,048 1984 2,250,000 836,655 160.000 167,390 160,000 136.080 147,280 57,420 45,000 107,315 4,067,140 1985 (E) 2.300,000 744.000 175.000 160.000 160,000 148.300 135.000 61,000 55.000 109.600 4,047,900 TO READ AND TO SEE Chrysotile Asbestos: A Material For Today And Tomorrow A 35 page colour brochure on the major aplications of asbetos, the saf^ and unsafe uses of this natural fibre and the risks inherent to the use of various substitutes. Available at: The Asbestos Institute or Ministere de I'Energie et des Ressources du Quebec Service de I'economie minerale 1620, boul. de I'Entente Quebec Canada G1S 4N6 Asbestos A review of chrysotile asbestos uses, of the health problems asso ciated with exposure to asbestos dustand of the application of regu latory standards and practices needed to ensure the safe use of this material. The document also underlines the responsibilities of those involved in establishing an acceptable JeveJ of risk and pres ents the recommended regulations as well as Canada's position on the controlled use of asbestos. (64 pages, colour photos) Available at : The Asbestos Institute or Energy, Mines and Resources Canada 580 Booth Street Ottawa Canada K1A0E4 Living with Asbestos A 17-minute video produced by the Ministere de I'Energie et des Ressources du Quebec, in co operation with The Asbestos Insti tute and Energy, Mines and Re sources Canada. In addition to explaining the cur rent conditions of the mining and processing of asbetos in Canada, the document presents several interviews with representatives of the workers, the industry and the governments on problems related to the use of asbestos and the pos sible solutions. The video is avail able in Beta and VHS V2 inch and in Va inch professional format. To borrow copies : Cinematheque Ministere des Communications du Quebec 1601, boul. Hamel ouest Quebec Canada GIN 3Y7 To order copies: Att: Yvette Lancup Service de la diffusion des documents audio-visuels Ministere des Communications 1037, boul. de la Chevrofiere Quebec Canada G1R4Y7 9 HWBUI0001406 ASBESTOS AND THE ENVIRONMENT Asbestos in Drinking Water: "No Assessable Risk," WHO Concludes n the basis of scientific stu among others, a commission of the Odies whose results have been European Communities and a Bri published since 1981, there seetmissh advisory committee on the to be a growing consensus to the issue. A number of experts, how effect that the ingestion of asbestos ever, recommended that new in drinking water poses no assess epidemiological and ingestion able risk to the health of the con studies be undertaken. sumer. This being the case, until scientific research proves the con trary, it is unlikely that the World Health Organisation (WHO) will consider it necessary to modify the advice it gave on this matter in its 1980-82 Guidelines for DrinkingWater Quality. On the basis of this early research, the EPA itself organized an exten sive program to investigate every aspect of the issue. Some projects were undertaken in collaboration with the National Institute of Environmental Health Sciences. It has been estimated that these It was in these terms that J.l. Waddington, director of the Environ mental Health Service of WHO's organizations invested at least 30 million dollars in various studies over a ten year period. Regional Office for Europe, stated the views of his organization on the issue of ingesting asbetos in drinking water. In a recent letter to Sir Neville Stack, Director General No Link Between Ingestion and Cancer In his letter to the AIA, Mr. Wad dington refers to a report that of the Asbestos International Asso ciation (AIA), Mr. Waddington in fact simply reiterated WHO's pre vious positions on the issue. These were formulated in 1980-82 on the basis of the scientific results and data available at the time, which aimed at determining whether var iable concentrations of asbestos in drinking water might have carci nogenic effects. It is a fact that tens of thousands of kilometers of asbestos-cement piping supply drinking water to millions of people around the world. Futhermore, drinking water springs are in permanent contact with natural deposits of asbestos, both underground and on the sur face. Sometimes as well, mine tail ings containing asbestos have been dumped into reservoir lakes. appeared in the May 1984 issue of The New Scientist. According to this report, of seven major studies carried out in the United States, Canada, the United Kingdom and Italy, five show no relationship between ingested asbestos fibres and gastrointestinal cancer. Dr. Selikoff's study of insulation work ers claims that such a link exists, but adds the rider that "no evi dence exists to show that drinking waterfrom pipes made of asbestoscement is hazardous". Only one of these studies, which was con ducted between 1978 and 1981 on the drinking water of five Califor nia counties in the San Francisco Bay area, found a relationship between this kind of piping and the incidence of cancers of the esophagus, stomach and pancreas; however, it has been recognized that various methodologies weaknesses and gaps considerabl reduce the value of these results. Along with this impressive array c epidemiological studies,since 196 numerous ingestion studies hav been successfully carried out o over 10,000 animals (rats, hamster baboons, etc.) The quantities at sorbed were considerably mor than a human being could inges In this regard, a round table cor vened by the EPA in 1982 declare that, in animals, ingested asbestc proved to be essentially non-carci nogenic. The EPA Contradicts Itself Again, as recently as August 198! the EPA concluded through one c its committees that the scientifi evidence currently available botl from epidemiological and anima studies does not support the viev that asbestos ingested in wate causes organ-specific cancers. One is year, the EPA announced its inten tion to propose a regulation limit ing the maximum fibre content k seven million fibres per litre fo fibres longer that 10 microns. Tc support such an option, th Agency appears to be counting or the eventual possibility of estab lishing a relationship between the ingestion of fibres longer than K microns and the incidence of gas trointestinal cancer. It even goes sc far as to see risks inherent in inhal ing fibres present in the water and sprayed into the air by humidifier* and shj^wers! It admits, nonethe less, thyit the data on this question is limited ! An Impressive Number of Studies In the United States, as early as 1974 the American Water Works Asso ciation Research Foundation com missioned a major review of the studies done on the issue up to that time. Conducted by a multidisci plinary scientific team including members of the Environmental Protection Agency (EPA), the study concluded that, regarding asbes tos-cement pipes, "the probability of risk to health from the use of such systems is small -approaching zero." Three years later,a special commit tee of the United States National Academy of Sciences arrived at these same conclusions, as did, 10 Course on Health Effects of Asbestos, Fundamentals and Controversies Dates : july 22-24, 1986 Place: Harvard School of Public Health, Boston. U.S.A. Information; Secretariat Office Continuing Education Department Harvard School of Public Health 677 Huntington Avenue Boston, Massachussets 02115 U.S.A. DATES TO REMEMBER 14th International Cancer Congress Dates: August 21-27, 1986 Place : Budapest, Hungary Information : Congress Bureau MOTES2 P.O. Box 32 Budapest, H-1361 Hungary Tlx.: 224-204 EVM/MOTESZ Fifth International Symposium: Epidemiology in Occupational Health Dates: September 9-11, 1966 Place: UCLA Campus, Los Angeles, Cali fornia, U.S.A. Information : Dr. David Wegman, Secretary Southern California Occupational Health Centre School of Public Health Los Angeles, CA 90024 U.S.A. HWBUI0001407 SCIENTIFIC INFORMATION A Swedish Study Confirms the Dose-Response Theory study (1) conducted in A Sweden by Drs C. G. Ohlson (2) and G. Hogstedt (3) on a cohort of 1176 workers of an asbestoscement plant did not indicate any asbestos-related excess mortality or increased risk of lung cancer. In their discussion, the authors suggest as a possible explanation for such results the relatively low levels of cumulative exposure and the predominant use of chrysotile in the plant's production. Their suggestion was supported by a comparison of their results with those of five other studies on asbestos-cement workers that report considerable differences in relative risks for lung cancer. The Swedish authors feel that, indeed, these differences could be ex plained by varying degrees of cumulative exposure, the amount of amphiboles used in the manu facturing process, and finally me>.?thodc>U>8al shortcomings. Study Croup and Period The Swedish cohort comprised all men workers employed at the plant for more than three months between 1943 and 1976. Originally this group totalled 1216 workers, but it was subsequently reduced to 1176, since 36 workers had emi grated from Sweden and four others had died before the period chosen for the observation of deaths. This period started in 1951, the year when the World Health Organisa tion's classification for death causes was adopted in Sweden, and lasted until 1982. The cancer morbidity was checked through the National Cancer Registry wich, however, covered only the period of 1958 to 1979 at the time of the study. Exposure to Asbestos Fibre The authors note that the data on asbestos exposure for the plant in question were rather scanty for the 1950s and 1960s. The few mea surements available indicated that during those decades the dust level was about 10 mg/m13 42and half that amount after 1970. Based on several hundred samples collected during five investigations made between 1970 and 1976, the aver age fibre concentration was esti mated at 1 f/ml for that period. Even though the manufacturing and handling of the asbestoscement products were the same in the preceding decades, the authors estimate the concentration to have been twice that level, or 2 f/ml, before 1970 because plant ventila tion was then inferior. The asbestos used in the plant was mostly of the chrysotile variety, but it was found that 630 tons of amosite were also used between 1949 and 1951, as well as 400 tons of crocidolite in 1962. The authors con sider that these quantities of amphiboles represent less than one percent of the asbestos used during the period covered by their study. Even though no personal exposure data were available for all cohort members, the authorsdid estimate the average cumulative exposure to be about 18 fibre-years for a subcohort of 125 workers with at least 10 years of employment who participated in a voluntary health examination in 1976. Similarly, smoking habits were not known for the entire group. How ever, a voluntary health survey made in 1980 among a sub-group of workers showed the smoker and non-smoker distribution to be closed to the national average. Results Related to Employment Time When the authors analysed the lung cancer mortality for various lengths of employment, with a 20 year latency time, they found excess mortality among workers employed less than two years (5 cases observed against 1.8 expected). A look into the pre vious work of the deceased revealed that two of them had worked on the docks, unloading bags of asbestos to be sent to the plant. According to the authors, such additional source of exposure could explain the high incidence of lung cancer in the less exposed group. What Drs Ohlson and Hogstedt cannot explain, however, is the reduced mortality from lung cancer among workers employed longer than five years (1 case observed against 2.6 expected). They feel that further follow up time may be of value in clearing up this point. A similar phenomenon of excess mortality among short term em ployees showed up in the analysis of deaths from virtually all causes (malignant tumours, diseases of circulation, diseases of the respira tory tract and violent deaths), independent of latency time. The authors note that such a pattern has also been observed in other cohort studies and suggest that it may be conditioned by individual risk factors, such as high consump tion of tobacco and alcohol, which tend to be more common among short term employees in some industries. Non-Significant SMRs For the entire cohort, the study showed 220 deaths under the age of 80 against an-expected total of 214, giving astandardized mortality ratio (SMR) of 103. It was observed that malignant tumours caused 44 deaths against 50 expected (SMR 88) and that lung cancer caused 11 deaths against 9 expected (SMR 123). With a latency require ment of 20 years, the standardized mortality ratio for lung cancer was 158, which is statistically non-signif icant. According to the authors, the absence of work-related excess mortality and the relatively low risk of lung cancer shown by these SMRs could be explained by the low level of cumulative exposure of the cohort (estimated average oi 10 fibre-years) and by near ly excl usive use of white asbestos in the plant's production. When comparing their results with those of five other studies (4) of asbestos-cement workers, Drs Ohlson and Hogstedt were able to ascertain that where the average levels of cumulative exposure were high or where amphiboles were used, the SMRs usually indicated increased risk of lung cancer. From this review, Drs Ohlson and Hogstedt conclude that long term employment in high concentra tions of asbestos fibres, giving a median cumulative exposure of 70 to 100fibre-years, increases the risk of lung cancer considerably, whereas this risk does not increase with a median cumulative expo sure of about 10 to 20 fibre-years. They also stress the fact that the lung cancer risk is relatively low when only chrysotile is used. (1) Lung cancer among asbestos cement workers. A Swedish cohort study and a review. Br J Ind Med 7985 : 42 : 397-402. (2) From the Department of Occupational Medicine, Medical Center Hospital, Obtero. (3} From the Departments of Occupational Medicine, National Board of Occupational Safety and Health and Karolinska Hospital, Stockholm. (4) The five studies are: Weill H. Hughes. J Waggenspack, C. "Influence of dose and fiber type on res piratory malignancy risk in asbestos-cement manufacturing." Am Kev Respir Dis 1979: 120: 345-54 Finkelstein MM. Mortality among long term employees of an Ontario asbestos cement factory. Br J Ind Med 1983: 40: 138-44. Thomas HF. Benjamin IT. Elwood PC. Sweetnam PM. Further follow up study of workers from an asbestos cement factory. Br J. Ind Med 1982: 39: 273-6. Lacquet LM. van der Linden L. Lepoutre J. Roentgenographir iung changes.asbestosis and mortality in a Belgian asbestos-cement factory. In Wagner JC. ed. Biological effects of mineral fibres. Lyon : IARC 1980. (Scien tific publications No 30). Haider M. Neuberger M. Comparison of lung cancer risks for dust workers, asbestos cement workers and control groups. Bio logical effects of mineral fibres. Lyon : IARC 1980. (Scientific publications No 30). 11 HWBUI0001408 CANADA Thetford Mines Asbestos Mining Activities Now Pooled ince April 1st, the three min Sing companies in the Thetford Thetford Mines area. Moreover, asbestos buyers will benefit from Mines region are combined withinimproved service and Increased a limited partnership whose name security of supply. has not yet been determined. This new venture is the product of almost a full year of study and negotiation. Objectives Structure The new limited partnership, which consists of three partners, is governed by a nine-member Board of Directors. Lac d'Amiante du The president of the new com Quebec has a 55% share and four pany, Jean Dupere, currently pres- seats on the Board. Asbestos Corp identand chief executive officer of Ltd. and Bell Ltd., both subsidiaries Lac d'Amiante du Quebec (LAQ), of the Societe Nationale de I'Ami- explained that it was "essential for ante, have a 22.5% share each and the Quebec asbestos industry to are represented by three members adjust rapidly to the new market on the Board. Camchib Mines, conditions that have developed in part-owner of LAQ mining rights, recent years". can appoint one director. The More specifically, the president of the limited partnership explained that this move would allow for ninth member of the Board will be chosen by unanimous consent of the partners. "maximum use of ore processing Mr. Dupere said that the new plants and substantial cuts in pro organization will operate all mines duction costs". Mr. Dupere is also and facilities belonging to the convinced that this reorganization three partners without legally will contribute to the long-term assuming ownership. The new preservation of the 1,500 jobs in the company will also market aU of the mines and processing plants in the combined companies' production. One of the mines in the Thetford Mines area. Current managements will be merged, but will remain decentral ized so that each facility stays under local management. Mr. Dupere underscored the strength and financial stability which this merger will give the partners. The three companies combined will produce 300,000 tonnes of asbestos fibre per year, equivalent to one-half of total Quebec production. In spite of the will continue to offer customers all grades of chrysotile asbestos. Mr. Dupere said that this reorgani zation "has the advantage of stabil izing the mining business in the Thetford Mines region by allowing a healthy level of activity and prof itability to be maintained". He added that "now is the time to apply the pragmatism and logic which will enable us to make the most of a unique product, a unique facilities, the limited partnership Canada and Quebec Intensify Their Effort to Promote the Controlled Use of Asbestos he Canadian and Quebec Tgovernments have decided to intensify their efforts aimed internationally promoting the con trolled use of asbestos. The broad outlines of their program, geared first towards the EPA proposal and the ILO convention in June, were recently unveiled by representa tives of the two governments. Canada's Minister of Mines, Robert E.J. Layton,and the Quebec Minis ter of State for Mines, Raymond Savoie, said on that occasion that they were encouraged by the con actlusions reached by scientists con sulted about the EPA proposal. Mr. Layton in particular repeated his conviction that the Agency's pro posal "is useless and unjustified from a medical, scientific or eco nomic point of view". He noted that in recent months the Cana dian government had held official discussions with representatives of several countries about the regula tions designed to restrict the use of asbestos and said that a second round of diplomatic initiatives was about to begin. Mr. Savoie in turn questioned "the rationale behind the relentless barrage of anti-asbestos publicity and the motives of some groups in the American administration for continuing to launch a regulatory process whose thrust was not always based on scientific fact". Citing recent studies on the hazards of asbestos, the Minister said that the Quebec government remained "convinced that adher ence to current standards provides adequate protection for the physi cal integrity of workers". The two ministers announced that the Asbestos Institute had been granted special subsidies to sup port the planned action. Each of the two governments would pro vide one million dollars in imme diate assistance, with the asbestos industry contributing in 500,000 dollars fora total of 2.5 million dol lars. It was also indicated that this extraordinary aid would be ex tended in the next three years and could, if necessary, reach as high as 10 million dollars. j\>U^Lrj`L) ASBESTOS is published by the Asbestos Institute, 1130 Sherbrooke St. West, Montreal, Quebec, Canada H3A 2MB. The Post Office Department in Ottawa has authorized postage paid in cash and forwarding of the publication by third class maiJ. Licho Canada m HWBUI0001409