Document zoN42LV1X5jnjnqvOOqyDd2D6

FILE NAME Packings and Gaskets PAG DATE 1976 Dec DOC PAG027 DOCUMENT DESCRIPTION Dept of Health - Revised Recommended Asbestos Standard REVISED RECOMMENDED ASBESTOS STANDARD | U. S. DEPARTMENT OF HEALTH EDUCATION AND WELFARE Public Health Service Center for Disease Control National Institute for Occupational Safety and Health DECEMBER 1976 For sale by the Superintendent of Documents U.S. Government Printing Office Washington D.C. 20402 VI THE RECOMMENDED STANDARD Available studies provide conclusive evidence that exposure to asbestos fibers causes cancer and asbestosis in man Lung cancers and asbestosis have occurred following exposure to chrysotile crocidolite amosite and anthophyllite Mesotheliomas lung and gastrointestinal cancers have been shown to be excessive in occupationally exposed persons while mesotheliomas have developed also in individuals living in the neighborhood of asbestos factories and near crocidolite deposits and in persons living with asbestos workers Asbestosis has been identified among persons living near anthophyllite deposits Likewise all commercial forms of asbestos are carcinogenic in rats producing lung carcinomas and mesotheliomas following their inhalation and mesotheliomas after intrapleural or ip injection Mesotheliomas and lung cancers were induced following even 1 day's exposure by inhalation The size and shape of the fibers are important factors fibers less than 0.5 ...m in diameter are most active in producing tumors Other fibers of a similar size including glass fibers can also produce mesotheliomas following intrapleural or ip injection There are data that show that the lower the exposure the lower the risk of developing cancer Excessive cancer risks have been demonstrated at all fiber concentrations studied to date Evaluation of all available human data provides no evidence for a threshold or for a safe level of asbestos exposure 92 ee meee we In view of the above the standard should be set at the lowest level detectable by available analytical techniques an approach consistent with NIOSH'S most recent recommendations for other carcinogens ie arsenic and vinyl chloride Such a standard should also prevent the development of asbestosis Since phase contrast microscopy is the only generally available and practical analytical technique at the present time this level is defined as 100,000 fibers 5 um in length 0.1 fibers on an hour basis with peak concentrations not exceeding 500,000 fibers 5 ...m in length 0.5 fibers based on a minute sample period Sampling and analytical techniques should be performed as specified by NIOSH publication NIOSH Membrane Filter Method for Evaluating Airborne Asbestos Fibers ~ T.R. 84 1976 This recommended standard of 100,000 fibers 5 ...min length is intended to 1 protect against the noncarcinogenic effects of asbestos 2 materially reduce the risk of asbestos cancer only a ban can assure protection against carcinogenic effects of asbestos and 3 be measured by techniques that are valid reproducible and available to industry and official agencies However some difficulties arise in that specific work practices and innovative engineering control or process changes are needed But because of the documented human carcinogenicity from all forms of asbestos these difficulties should not be cited as cause for permitting continued exposure to asbestos at concentrations above 100,000 fibers 5 ...m in length 3 93 This standard was not designed for the population and any extrapolation beyond general occupational exposures is not warranted The standard was designed only for the processing manufacturing and use of asbestos and containing products as applicable under the Occupational Safety and Health Act of 1970 24 + si criteria for a recommended standard | | j | OCCUPATIONAL = EXPOSURE / ASBESTOS U.S. Department of Health Education and Welfare Public Health Service Health Services and Mental Health Administration National Institute for Occupational Safety and Health 1972 For sale by the Superintendent of Documents U.S. Government Printing Office Washington D.C. 20402 ' I. RECOMMENDATIONS FOR AN ASBESTOS STANDARD The National Institute for Occupational Safety and Hea-l NIt OShH recommends that worker exposure to asbestos dust in the workplace be controlled by requiring compliance with the following sections Control of worker exposure to the limits stated will prevent asbestosis and more adequately guard against asbestos neoplasms The standard is amenable to techniques that are valid reproducible and available to industry and governmental agencies It will be subject to review and will be revised as necessary Section 1 - Environmental work place air a Concentration Occupational exposure to airborne asbestos dust shall be controlled so that no worker shall be exposed to more than 2.0 asbestos fibers per cubic centimeter cc of air based on a count of fibers greater than 5 micrometers 5 ...min length determined by the mem- brane filter method at 400-450X magnification 4 millimeter objective phase contrast illumination as described in Appendix I determined as a weighted average TWA exposure for an hour work day and no peak concentration of asbestos to which workers are exposed shall exceed 10.0 fibe5 rs ...m as determined by a minimum sampling time of fifteen minutes b Sampling Procedures for sampling calibration of equipment and analysis of asbestos samples shall be as provided in Appendix I. c It is recommended that this Section I become effective two years after promulgation as a standard and that until the date of publication the present emergency standard for exposure to asbestos dust 29 CFR 1910.93a shall be in effect This period is believed necessary to permit installation of necessary engineering controls 2 Section 2 - Medical Medical surveillance is required except where a variance from the medical requirements of this proposed standard have been granted for all workers who are exposed to asbestos as part of their work environment For purposes of this requirement the term exposed to asbestos will be interpreted as referring to weighted average exposures above 1 fiber cc or peak exposures above 5 fibers The major objective of such surveillance will be to ensure proper medical management of individuals who show evidence of reaction to past dust exposures either due to excessive exposures or unusual susceptibility Medical management may range from recommendations as to job placement improved work practices cessation of smoking to specific therapy for asbestos disease or its complications Medical surveillance cannot be a guide to adequacy of current controls when environmental data and medical examinations only cover recent work experience because of the prolonged latent period required for the development of asbestosis and neoplasms Required components of a medical surveillance program include periodic measurements of pulmonary function forced vital capacity FVC and forced expiratory volume for one second FEV1 and periodic chest roentgenograms anterior 14 x 17 inches Additional medical requirement components include a history describe smoking habits and details on past exposures to asbestos and other dusts and to determine presence or absence of pulmonary cardiovascular and gastrointestinal symptoms and a physical examination with special attention to pulmonary rales clubbing of fingers and other signs related to cardiopulmonary systems Se. Chest roentgenograms and pulmonary function tests will be performedperformed at the employer's expense at least every 2 years on all employees exposed to asbestos These tests will be made annually to individuals 1 who have a history of 10 or more years of employment involving exposure to asbestos or 2 who show roentgenographic findings such as small opacities pleural plaques pleural thickening pleural calcification which suggest or indicate pneumoconiosis or other reactions to asbestos or 3 who have changes in pulmonary function which indicate restrictive or obstructive lung disease Preplacement medical examinations and medical examinations on the termination of employment of asbestos exposed workers are also required Section 3 - Labeling a A warning label for asbestos as shown in Figure 1 shall be used b Numerical designations indicate the following i * Health Hazard color code blue Inhalation may cause asbestosis pleural or peritoneal mesothelioma or lung cancer 1 = Fire Hazard color code red Asbestos is flammable and has negligible vapor pressure volatility flash point and explosive limits c The details of the numerical hazard rating system are found in Appendix II - ASBESTOS HARMFUL May Cause Delayed Lung Injury Asbestosis Lung Cancer DO NOT BREATHE DUST Use only with adequate ventilation and approved respiratory protective devices RS Se Summary of the Basis for the Recommended Standard The recommendation for an environmental standard for asbestos is based upon health considerations and limited engineering feasibility data The overriding considerations are the health effects Evidence indicates that past and current standards for fiber concentrations in the working places where asbestos fibers occur though undoubtedly contributing to reduction of the severity and frequency of asbestosis have not provided complete protection from exposure to asbestos necessitating development of a new standard Consideration was given to previous reports and studies recent data and the present state It is recognized that additional data would be desirable to support an asbestos standard but because of immediate need for worker protection it is necessary to make a recommendation based on available studies and data The following constraints in applicability of research data were considered in the eet development of the recommendations Sener a Few epidemiological studies or clinical reports with supporting environmental data are available in the exposure range that must be considered b Environmental data on practically all studies were collected only over the last few years and they were collected by other techniques and expressed in terms other than fibers c The environmental samples were expressly collected in many cases for control purposes rather than for research and as a result meaningful evaluations cannot be made 16 d There is a lack of data to define with any degree of precision the threshold of development of neoplasms resulting from exposure to asbestos and the relationship of the latent period between exposure and development of neoplasms The standard recommended in this document is similar to the standard 66 adopted by Her Majesty's Factory Inspectorate in 1969 still in effect as of December 29 1971 and more stringent than the recent U. S. Emergency Standard It is felt to be feasible technologically for the control of the exposure to the worker and effective biologically for protection of the worker against asbestos diseases Considerations of carcinogenesis indicated the need for a measure of prudence As a result of this rationale a factor was added to reduce the weighted average exposure to 2.0 fibers um A ceiling value of 10.0 fibers um that was not to be exceeded was included to reduce the possibility of the short heavy exposures to asbestos that have been reported to cause mesothelioma In addition this should reduce the likelihood of diseases malignant and malignant resulting from exposures in excess of 30 years or with very long latent periods 17 TABLE III STUDIES OF HUMAN POPULATION CARCINOGENICITY Author Date Finding Group and Exposure Occupational Exposure Historical Studies Lynch and Smith Gloyne Wedler 1935 Suspicion of association Asbestos workers 1935 Between asbestos and lung cancer " " 1943a Case reports of pleural and peritoneal tumors associated to asbestos Doll Mancusco and Coulter Selikoff 1955 Lung cancer 1963 1964 Lung cancer and mesotheliomas " Asbestos textile workers employed before 1930 Asbestos workers " 54 Epidemiological Studies Lung Pleural and Peri- toneum Mixed Types of Fibers Newhouse UK Bohlig et al FRG Selikoff et al USA Elmes and Simpson UK Stumphius Netherlands Rubino et al Italy Selikoff et al 1969 1970 1970 1971 1971 1972 1973 Bronchial cancer pleural and peritoneal mesotheliomas " 11 11 " " Lung cancer Enterline and Henderson 1973 Respiratory cancer Harries Edge 1976 1976 Mesotheliomas Carcinoma of bronchus Asbestos manufacturing insulation and shipyard workers 11 TI " 11 Insulation workers chrysotile and amosite asbestos exposure Retired production and maintenance workers in asbestos industry Naval dockyard workers Shipyard workers oraoi Secae Nt ams TABLE III CONTINUED STUDIES OF HUMAN POPULATION CARCINOGENICITY Author Date Finding Group and Exposure Mixed Types of Fibers DeLajarte et al France 1973 Gobbato and Ferri Italy 1973 Webster South Africa 1973 Greenberg and Lloyd 1974 Davies UK Hain et al Fed Rep 1974 Germany Nurminen Finland 1975 Stunn Ger Dem Rep 1975 Zielhuis The Netherlands 1975 Evidence of association between mesotheliomas and past exposure to asbestos tt ff " " " " " " Occupational exposures in some cases as brief as one day " " = = = = " = Newhouse et al " 1973 Peritoneal tumors associated to heavy exposures 55 Gilson " 1973 % to % asbestos workers deaths due to mesotheliomas " Hammond and Selikoff 1973 " " Selikoff 1976 " Newhouse and Berry 1975 11 asbestos workers deaths due to mesotheliomas Single Types of Fibers Crocidolite Wagner 1960 Pleural and peritoneal cancer Harrington et al Webster McNulty Jones et al 1971 1973 1962 1976 Mesotheliomas " " Workers in mines mills and in transportation and handling of crocidolite and population in vicinity of mines Mining population of crocidolite mines Miners of crocidolite Women working with crocidolite in WWII gas mask canister factories TABLE III CONTINUED STUDIES OF HUMAN POPULATION CARCINOGENICITY Author Date Finding Group and Exposure Chrysotile McDonald et al Kogan et al 1973,1974 Lung cancer 1972 Total cancer Lung cancer Chrysotile mine and mill workers Workers in asbestos mining and milling men and women Wagoner et al 1973 Respiratory cancer 11 Enterline and Henderson 1973 Workers in manufacturing of textile friction and packaging products using chrysotile Men 65 yr and older retired production or maintenance employees in asbestos industry exposed only to chrysotile Borow et al Amosite 56 Gilliam et al 1973 Mesotheliomas 1976 Malignant respiratory disease Workers at plant using chrysotile all ages Miners exposed to amphibole fibers in cummingtonite ore series Selikoff et al Anthophyllite Neurman et al 1976a Mesotheliomas lung cancer Insulation workers in factory using amosite 1974 Bronchial cancer dyspnea and cough Anthophyllite mining employees Other Cancer Mancuso and El Attar Elmes and Simpson Kogan et al Newhouse Wagoner et al McDonald et al Selikoff et al 1967 1971 1972 1973 1973 1974 1974 Cancer of gastrointestinal tract 11 " " " " " Asbestos workers 11 " 11 tt " tt Stell and McGill Morgan et al Newhouse and Perry 1973 Squamous carcinoma of larynx 1976 1973 Cancer of larynx Workers with exposure to asbestos Asbestos workers TABLE III CONTINUED STUDIES OF HUMAN POPULATION CARCINOGENICITY Author Date Finding Nonoccupational Exposure Anderson et al 1975 Mesotheliomas Wagner et al " 1960 Newhouse and Thompson 1965 Bohlig and Hain 1973 Gilson " 1970 ' Greenburg and Lloyd 1974 Davies Kiviluoto 57 1960 Pleural plaques Other Studies Newhouse Newhouse et al Howard et al Cooper et al 19691972 Cancer mesothelioma wt 1976 Lung cancer 1975 Group and Exposure Family members of asbestos workers Individuals in neighborhood of industrial sources of asbestos New cases from areas with recognized industrial source of asbestos Persons in farming region of Bulgaria where minute quantities of anthophyllite tremolite and sepiolite in soil and nonoccupationally exposed persons in anthophyllite mining area of Finland Women factory workers exposed to chrysotile amosite and crocidolite Workers in asbestos industry from 1933 to 1950 and after 1950 Sheet metal workers with 5 or more years exposure