Document jgGzDgMjXR1EYG3gYy7XxeEZ5

ASBESTOS INFORMATION ASSOCIATION/ North America 1835 K Street, N. Vi. Suite 402 Washington, D. C. 20005 A modern health controls are effective The health -oLasbg.stos workers has been a matter of concer'n~To~jovefnrneftts and industry alike, and some legislation has been in effect for over 30 years to control working conditions. There are some hazards to health caused by exposure to asbestos fibres, but the effects usually become observable only after many years. Hence sickness may occur today in people who worked with asbestos in the 193135, and the positive preventive re sults of recent and current controls may not be apparent for some years in the future. At a recent meeting of the Vancouver branch of CIM, a talk about asbestos today was given by Peter Steen, president of Cassiar Asbes tos Corporation. It is summarized here. In recent years there has been a frantic rush to publicize man's growing array of environmental problems. Asbestos has become one of the prime targets. The asbestos industry is aware of the health hazards that ctin arise, has done a lot to ensure safety for its workers, and wel comes constructive well-researched and documented information. The industry rejects broad and generalized statements about asbestos and health made by unqualified people who masquerade unsupported opinion as fact -- and sensationalism as honest comment. Asbestos is the generic name for a group of hydrated silicate minerals that can be separated into relatively soft silky fibres which have great tensile strength. It is classified into six types of two groups, pyioxencs and amphibolc, ac- cording to molecular structure and phys ical characteristics. Chrysotile asbestos (pyroxene group) accounts for over 90% of world asbestos production, and 97% ofall asbestos used in Canada and the United States. Canada and the USSR are the leading producers of this type of asbestos. Amphibole types make up the remain ing 10% of world production. Amosite is mined commercially only in the Eastern Transvaal area of South Africa, and is used mainly to make heat insulating materials. Crocidolite (a fcrTOus sodium silicate) comes mainly from the North West Cape Province and Eastern Trans vaal in South Africa; it has high acidresistance. Asbestos is Ere-proof, rot-proof, and impervious to water; it can be made into types of textiles or paper, and is used daily in an estimated 3000 products. It was known for nearly 2000 years before its properties were first seriously investi gated in 1873. HEALTH Like many materials in common use, asbestos is quite safe if it is handled properly, which means with certain pre cautions. Dr H C Lcwinsohn, a world authority on occupational health, has stated 'Asbestos dust, like the dust o." many other basic industrial materials, can be a hazard to health of people exposed to it in high concentrations. It is important that the risk should be clearly understood and that proper controls be exercised over the mining, manufacture and industrial use of the material'. There arc three diseases associated with exposure to asbestos fibre; asbestosis, lung cancer, and mesothelioma. Asbcstosis is a type of pulmonary fibrosis, the result of inhaling high con centrations of fibrous asbestos dust, usually over many years. Lung cancer incidence may be in creased in workers who have asbcstosis associated with excessive asbestos ex posure. The cause is not known, and asbestos is the subject of much medical research, along with other carcinogens, including coal tar, benzidine, tobacco, vinyl chloride, x-rays, and even sun shine. However, few (if any) asbestosrelated lung cancers have been found in otherwise healthy asbestos workers who do not smoke. Cigarette smoking com bined with asbestos exposure can pro duce an effect in which the risk is multiplied as much as 90 times. Mesothelioma, a rare and newly rec ognized disease, is a malignant tumour in the lining membrane of the chest and abdominal cavity. By no .means are all such tumours asbestos-related, but where there is a relationship it has been found mainly with crocidolite fibre. Far fewer cases have been found where the exposure has been limited to chrysotile fibre -- the type mined in Canada. FACING THE FACTS Recently, some unions, media, govern ment bodies, and even medical au thorities have dwelt at length on asbestos and health. Unfortunately these often well-meaning people failed to balance the story. To give just one side of the story is at best thoughtless and at worst downright dishonest. Discussing 139 new cases of asbestosisin the year 1974, HM Chieflnspector of Factories, in the United Kingdom, stated; 'These continued to reflect condi tions in past years when the long term effects of asbestos dust o.< health of asbestos workers was not fully ap preciated, The latent period for this disease is such that annual figures cannot yet be expected to reflect improved conditions following the introduction of new legislation in 1970.' People in industry are responsible and concerned for the health of employees and their families. Neither employees nor management will reach their respec tive environmental goals if they waste their time, money, and resources indulg ing in labour-management standoffs on how environmental goats are to be achieved -- and when. Nobody knows the' final answers about asbestos and health; only that excessive asbestos inhalation over a long time can be linked to respiratory dis eases. Many of the statistics which arc being quoted today pertain to cases initiated in the early part of the century, when working conditions were radically different from those of today. 18 WESTERN MINER CAPCO JEN 0002803 Since those' days tricrc have been tremendous advances in almost every field of human endeavour, including the mining, milling, and processing of asbes tos. Hut. like everything else, it took time and it took its toll in suffering and human life. EARLY PRECAUTIONS Asbestos was first suspected of being hazardous back in the 1920s, in Great Britain. when someoftlic first asbestosis cases in history were recognized. Legis lation was passed in the 1920s and 1930s to define dust concentrations in asbestos processing factories, and asbestosis was made a compensable disease, much like silicosis in the mining industry. Though the legislation applied only to asbestos processing plants (there were no asbestos mines in Britain), it did focus attention on possible hazards in other areas, and tended to improve conditions in the mining and milling phase of the industry. As a result, the fiequcncy of asbestos-related disease started to de cline; however, the effects of exposure experienced before the 1930s are still to be seen today. In the early 1930s British factories processing or using asbestos found signs of asbestosis in some 80% of employees with twenty or more years of exposure. In 1957 at the same factory, but after installation of dust controls, the preval ence of asbestosis had dropped to 3% among workers with 20 years or more exposure. Lung cancer under pre-1933 conditions was ten times that of the general population; in 195S, in men not exposed before 1933, lung cancer was reported at the same level as the general population. The Canadian asbestos industry has one of the lowest disease rates in the world. Industry, unions, and govern ment are vigilant to ensure dust limits arc maintained or that workers are properly protected should higher dust rates occur for technical or other reasons. A Canadian study of fatal (nalignant mesotheliomas (1959-68) concluded that high risk was in the field of commercial manufacture and industrial application, and not in mining and milling. A three-year survey by McGill Uni versity reported: 'that even 30 years exposure to present levels of dust in modern asbestos mills would probably not carry any measurable risk of lung cancer. A sample group of 10,421 past and present production workers in Quebec were found to have a mortality rate from all causes lower than the level expected in the general Quebec popula tion'. In over 22 years of operations at Cassiar mine there has not been one reported case of asbestos-related dis ease. Records of employees' health and of dust concentrations have been kept at Cassiar since operations first started. From August 1953 to May 1967 the Workers' Compensation Board of BC did regular dust sampling; since 1967 the program is handled by the BC Depart ment of Mines and Petroleum Re sources. Regular surveys of dust con centrations are carried out by the com pany, and regular chest x-nty records are kept. Through all the yearsofCassiar opera tions to early 1975 average dust readings were within permissible limits, and con tinued to decline asa result of companyinitiated programs. However, early in 1975 when average dust samples all met the criteria, the criteria themselves and the method of sampling were altered. The sudden change led to a period of intense turmoil, misunderstanding, a work stoppage, and a tremendous waste of time, effort, and money. Cassiar welcomes government con cern and clear sensible legislation. In this case it would have welcomed an invita tion to participate, with the union, in setting new standards and arriving at a reasonable timetable for implementing them. Long before the new rules were introduced in 1975, Cassiar had a fiveyear plan to equip the mines with the latest and best protective devices. Now, average dust levels meet the new criteria, though some specific areas do not; but they will when the continuing program to upgrade the total environ ment is completed. ENVIRONMENTAL PROGRAM From a study made before 1975, design engineering is under way for installation of a new air filtration system, which should be on stream by 1978. Other equipment is to be upgraded, and an additional 480,000 ft'/min capacity pro vided. A new change house is being designed; a central vacuum-cleaning sys tem is nearly complete. Small portable vacuum units are used to supplement the central system. Some of these programs were already under way before the changes to standards were announced. Protective clothing and other dust control precautions are available for asbestos workers and their families, which includes members ofmanagement who also work and live in the same ateas -- a fact that is sometimes ignored by critics of industrial management. In the open pit mines, mobile equip ment operators are protected in pres surized cabs, with filters to keep the dust out; dust from drills is also filtered and extracted, to keep it from the atmos phere. In the crushing, drying, and milling areas, ducts and control areas extract dust from working places. The contami nated air is filtered to remove dust. Ore-drying exhausts are fitted with high-temperature fabric filters. Fine mil ling wastes and collected dusts are wet ted and agglomerated before they arc discharged from the mill; the tailings pile today is virtually dustless. In comparison to asbestos processing techniques that once existed decades ago, the industry has advanced a long way in recent years. Today's asbestos worker has little to fear fiom dust hazards when proper care is exercised in handling this important mineral. Responsibility for ensuring employee safety and health is willingly shared by industry with government, unions, and the individual. There is still room for improvement, and this can best be achieved through mutual concern and respect, and a desire to increase co operation and reduce confrontation. MARCH 1976 WESTERN MINER CAPCO JEN 0002804