Document qaGRNpjVzR4ox4rNjoX8G4MRj

> CARCINOGENS um In view of today's increasing amount of technological by-prod ucts, health and safety specialists are now beginning to judge these products, and consequently other materials found in our environ ment, upon broader criteria. Among the more significant of these criteria is the carcinogenic risk factor. With cancer-causing agents so prevalent in our news headlines and therefore in the public mind, it becomes of great importance that no unnecessary alarms be set olT as a result of inadequate assessment methods, which pre maturely indicate a cancer risk. Such was the case in the evalua tion of the cancer risk of asbestos in building materials and insula tion. A recent five-year study now reveals that both the seriousness and the magnitude of the cancer risk of asbestos have been over stated and, in fact, are minimal in most cases. The study was conducted by Industrial Hygienics, Inc. (IHI), a leading occupational and environ mental health consultant. The results of the study were first made public at the 1980 American Industrial Hygiene Conference, By James T Schirripa. CIH, President, Board Chairman, Industrial Hygienics, Inc . Huntington, NY Diplomate of American Industrial Hygiene Academy Evaluating the cancer risk of asbestos When the hazard involved is a carcinogenic risk, and the population exposed varies from children to senior citizens, the complexity is increased significantly. held in Houston, Texas, attended by over 5,000 of the nation's indus trial and governmental health pro fessionals. DATA The IHI asbestos study was based on data collected from standard NIOSH techniques, cer tified test methods which relied on Data indicate that the seriousness of asbestos risks is overstated. over 400 air samples, analysis, data interpretation and risk limi tation. Over 100 general occupancy buildings, located in urban, sub urban, rural and natural envi ronments, including: schools, churches, offices, hospitals, li braries, industrial plants, ships in port, and businesses, were in volved in the study. The study presents data on 40 of these buildings where the source of the asbestos fiber was insulat ing materials either sprayed on for fireproofing or used on pip ing. The air samples were taken in environments with asbestos in stallations to measure the concen tration of fibers. Then the amount of time it would take to develop a tumor (or the carcinogenic factor) was calculated for the general population exposed to these envi ronments. This time-to-tumor equation and model were previously used by federal agencies in establishing asbestos standards. (The Consum er Product Safety Commission used this equation and model in banning asbestos wall patching materials.) RISK? The time-to-tumor calcu lations, based on the levels found in these environments showed that the risk of cancer was negligi ble. The time-to-tumor exceeds the reasonable life span of persons exposed. In reaching the conclusion to ward the assessment of health hazards of asbestos installations, the IHI staff was hampered by several significant factors. There was the population risk in a cross section of the general pop ulation (infants to senior citizens) to contend with, and also the vary ing exposures periods existing in the different general occupancy buildings. For instance, in visits to a public building, an exposure could be as short as five minutes; while school children are subjected to expo sures to up to seven hours, and men at sea, aboard ships, would be subject to exposure of twenty-four hours and longer. JULY/AUGUST. 1980 45 BRG 0757 The decision-making process in the asbestos study was further complicated by the fact that the hazard to which people were potentially exposed is a "carcino genic risk." HINDRANCE And finally, hinder ing the delivery of accurate results was a lack of established asbestos The first sophisticated measurements of asbestos fibers were recorded. exposure criteria for these general populations and the usual imprecisions that scientific studies are subject to in the collection and analysis of environmental sam ples. Still, despite these factors, the IHI study had set before it the task of determining what, in fact, was the actual risk of carcinogene sis as presented in the various microenvironments studied. Previous attempts to determine the carcinogenic risk of asbestos in general occupancy buildings involved a test method suggested by the Environmental Protection Agency (EPA) which relies on a physical inspection of the particu lar building and the assigning of scores to various observations of the state of the insulation materi al. This testing method was to be carried out by school administra tors and other school personnel. Based upon the total score or "exposure number" assigned to a building, corrective measures were recommended. In IHI's assessment of the car cinogenic risk of asbestos, the basis of the test method employed involves an environmental mea surement technique that can be used to measure concentration of asbestos fibers in the buildings. This measurement method was the standard "(USPHS/NIOSH) Membrane Filter Method in Eval uating Airborne Asbestos Fibers." If conducted properly, unlike the EPA test method, it does provide an objective method for risk esti mation and risk limitation. TEST METHOD In addition to its more objective, scientific nature, IHI chose this test method on the basis of several other factors. This method is generally used for health hazard assessments in occupational environments. It is a method for which there exists an analytical quality control program-NIOSH-Proficiency Ana lytical Testing Program-and American Industrial Hygiene As sociation certification. Further, there are dose/response data (for cancer) based upon environmental data collected using this method; and, non-occup&tional exposures to asbestos have been regulated in the past on data generated by this method. In using this scientific method, the first sophisticated and accu rate measurements of asbestos fibers in closed environments were recorded. According to the IHI study, the general level of asbestos fiber in the air of those buildings tested was 0.10 of a fiber per cubic centi meter or lower. The cancer risk reported from IHI's study was small, if not negli gible. In a building sampled and showing the highest asbestos lev el, the rate of potential cancer The delivery of test results is hindered by a lack of criteria. cases due to continuous exposure would be 112 cases per million in the population over 40 years, or 2,707 cases in 75 years. INCREASED RISK Ironically, the IHI study further reveals that this rate of cancer is increased by 20 times once the asbestos has been disturbed as in removing it. Or, similarly, it concludes that the risk of doing something (removing asbestos insulation) increases the rate of potential cancer cases from 112 cases per million in the popula- 46 OCCUPATIONAL HEALTH AND SAFETY BRG 0758 lion over H) years, to 2,21."i cases per million in -10 years, or' 12.24!) cases in 7'> years. Heynnd nUVring the scientific measurements of the levels of asbestos libers anil the assess ment of the carcinogenic risk from exposure to these levels, the IHI Movement of asbestos fiber insulation increases potential cancer risks. study focuses attention on the sig nificance and need for more for mal, scientific studies in the assessment of potential health hazards. In situations such as that of the asbestos insulation expo sures, where the lives of many people are allotted, and where huge sums of money are allocated toward reducing potential risk factors, it is at once imperative that accurate scientific testing be the foundation for any reports, and measures he taken toward alerting or reducing the potential health hazards posed by a certain material in either the natural environment or given occupation al settings. With respect to the asbestos in building materials and insulation, many new substitutes have been found. In future installations, of course, these new substitutes should he used in order to prevent any potential hazards, no matter how minimal. For buildings which already have asbestos insulation, it is essential that formal health haz ard assessments be made by cer tified health professionals toward correction and reduction of any existing hazards. Above all, asbestos insulation should not be removed or dis turbed in an effort to reduce a minimal carcinogenic risk which, again, becomes greater by a factor of 20 t imes with the disturbance of the fibers. Instead, a concerted effort should be made by our nation's health and safety profes sionals toward educating and in- I forming the general public of the actual carcinogenic risk of asbes tos insulation in general occupan cy buildings. The assessment of health haz ards is an area of some complexi ty. When the hazard involved is a carcinogenic risk, and the popula tion exposed varies from children to senior citizens, the complexity is increased significantly. There are no easy ways or quick formula to apply that will give instant direction for controls. The meth ods that need be applied are those that consider all of the variations and complexities of the situation. Competent health professionals, trained and experienced in envi ronmental health can and do pro vide the basis for the reduction and elimination of health hazards. The use of scientific methods and professional judgement will go a long way in protecting the health of the population. OH&S MANAGEMENT DECISIONS: an occupational health system can be hard or easy to manage Monitor makes it easy You can pay too much or spend too little on all the bits and pieces of an Occupational Health System and not even comply. Neither way is right for you! I chose the most appropriate services to help manage my system, at the least cost. For example: Instead of wading through piles of OSHA regulations, Monitor helped me plan the most practical program from A to Z. A plan that was easy to implement, and saved a lot of time and extra expense. Instead of worrying about the com petency of my occupational health technicians, I chose proven and practical NIOSH and CAOHC approved training by Monitor. Instead of wrestling with cumber some computer printouts of each em ployee's audiometric or pulmonary hll m ihe boxes staple your card aiki nt.itl ibis ,ul I ,trn interested in G Planning i nnsultatmn QOn site testing G let hmt un training O Equipment U tbil.t management hit L<Respiratory suiveilldnoe nHeanngtonservahon For more facts function test results, I chose MONIFAXTM-- a complete data report and management system. Monitor offers no more and no less than exactly what you need. I call this APPROPRIATE SERVICE: A refreshing professional approach to occupational health management. And Monitor has the expertise I trust, like a former OSHA health scientist who worked on the regulations. You'll find Monitor representatives extremely responsive to your needs. For example, they provide an implementa tion cost comparison. You'll find out how much can be saved by doing it the way that's right for you. He., much easier can Monitor make the business of managing an Occupational Health System? Find out for yourself. today. Monitor me Monitor makes it easy P O fln 2267 Chapel Hill \C 27S14 cle 21 on card |9i^i %* 2J2H .JULY AUGUST 1980 47 BRG 0759