Document ppXQo5Zeq0mR9LYq1Dy2gvwZk

- Insulation Hygiene ' Progress Reports ` VoL 7 No. 3 and 4 Winter 1975 -r - --- from the. .- % IrguUhoo Induccrf Hygiene Research Pro . gram............... . ZOkcn W. J. Wlrhihaa. IVJk, pahtiihrd the EniiouiueaeiSciBoaLahetrr(&vimi. SftKtotC. M.D., Dicuor). Moans Sinai School of Meddne ofthe City Univcauty of Hew York. N.Y. 10029 - . a4yWj Cwd ctuaar lrrio| J; SeUkoff, M.D.. ftofnen Dinecxcr bm! . Cuykar Hwnmoorf. Sc.D.. Vice President. American Cancer Society, New-Ycffc. N.Y. Andrew Haa*. General Ptrridew. iDtemaoooaf Aiaociacion of Hean and fro* boalaors read Aabemot Wottrn. Waohmiton. D.C. PURPOSES OF THE INSULATION INDUSTRY HYGIENE RESEARCH PROGRAM 1. To develop improved meth ods for minimizing exposure of insulation workers to dusts and fumes encountered in their work. 2. To disseminate knowledge of . these improved methods of dust control wherever they may be applied advantageously and to offer cooperation, advice and as sistance toward1 their universal adoption. . - . Asbestos Risk ixists :;. ; . fiord Use of Taping Compounds- . In spite of the. Introduction of asbestos-free insulation materials and* the existing bans oh the. use of asbes tos-containing spray fireproofing, a serious asbestos hxxard remains in the construction industry, with members of the. Painters Brotherhood of the Build ing and Construction Trades Depart ment being at greatest risk. Wallboard finishing compounds and speckle have been found to contain significant amounts of chtysodle asbestos, which - is released into the air as dust either during the dry mixing of these com pounds or during sanding.. ' Drywall taping compounds came into widespread use shortly alter World War II. Until fairly recently, most of the material used was mixed at the con struction site,, raising' Urge clouds of dust. In the past few yean, many con tractors have switched to premixed compounds,, thereby eliminating one major source of asbestos dost. This practice, though, depends entirely on the contractor and what he supplies; several capers interviewed recently by Mount Sinai personnel said they still had occasion to use the dry-mix brands. Sanding can be Dangerous The problem that remains, eves when ready-mixed compounds are used, is that of the dust produced when the dried compound is sanded, prior to painting. In some areas of (be country, tapers, or their apprentices, stay and do their own sanding; in others, the paintera are left to finish the job, often sand ing while other men are working in the same room. Sanding is done either by hand or with a pole; The Environmental' Sciences- Lab oratory took air samples at selected job sites in New York"City while tapes were at work. Personal samples taken during pole sanding ranged from 1.2 fibers per milliliter (f/ml) to 19.3 ffmli in an adjacent room, at a of 25. fret from the sender, a level of 8.8 Owl was found. Levels for hand sanding ranged from 1.3 to 16.9 f/ml in the breathing zone of the workers, and a high of 7.1 f7ml was obtained in an adjacent room, ax a distance of 15 feet. During dry mixing, a breathing zone sample was found to contain 59 f/ml, though after a 15-minute lapse the level went down to.0.5.f/mL"-" . The sweeping of floors after sanding was also found to stir up considerable quantities of settled dust. Thirty-five TM after sweeping at the site ofthe sanding, a fiber concentration of 26.4 f/ml was obtained. The current U.S. standard in industryis an avenge not to exceed5 f/ml, mandated to go to 2 f/ml in July, 1976. The Department of Labor has reccndy initialed procedures to have the standard lowered to 0-5 f/ml. The results of this sampling, espe cially when contrasted with the current standard in industry, emphasize the im portance of both respiratory protection and careful cleanup in order to reduce the risk of inhaling asbestos fibers. A respirator should be worn by sandera . and by any other workers who must be in adjacent areas while this work is in progress. If possible, other workers should wait to allow the dust to settle and be removed before proceeding with Continued on page 4 ! INew miormanon uu nraim JUJU.VA/U3 djrom page l where it appears that average exposure pprroosseed against the vuiom asbestos zRcexs. Important new information has been forthcoming subsequent to the promul gation of the current U.S. standard. This has included data obtained by Des. levels would often be considerably less, thus the projected 2 17ml standard. Shipbuilding Data Important. "Of considerable industrial impor tance has been the recent description of Irving J. SclIkofF and E- Cuyler Ham. asbestos among shipbuilding mood on the mortality experience of all and ship repair workers, few of whom insulation workers in the United States. actually work with,asbestos, buz many This large research project showed up. of whom were, in the past, inadver equivocally tbc high risk of ["ng tently exposed to the asbestos dust re and mesotnelioma experience bv a^.. sulting from the use of asbestos prod oexios worren. and m addition, dem- ' ucts by a reiarively few of tbeir work onsiraied that gasuo-mtestinal cancer mates. In 1968, Harries of the Royal Wg~5Bo increased In incidence among Navy reported cases of mesothelioma CBCTSr-ggnEen. Aa data rromdus among shipyard workers at the Royal huge sliuly were reviewed; irwas- sugr- -Navy dockyard in Devoopon. in trades gested that the risk of developing which did not directly involve .workers cancer of the larynx, oropharynx, or exposure to asbestos, but in which there . esophagus was also increased from as had been occasional opportunity for bestos exposure. Research with the In- exposure merely by virtue of working (creational Association of Heat and in the same areas. This original finding Frost Insulators and Asbestos Workers has-been widely confirmed and numer was quoted many times by the Depart, ous cases of mesothelioma hare since roent of Labor. Further studies of other been reported in former shipyard work large groups of workers occupationally ers. Studies of populations of current ^xposed to asbestos m factory employ- shipyard workers have shown much ^^Knt or mining and milling also info- . radiological evidence of asbestos ab ^BCted excess carcinogenic risk. normalities among workers in trades New Information only indirectly exposed to asbestos in the yards." The Department of Labor particu "Further, evidence has indicated larly noted information forthcoming that asbestos also acts as a lung car from the British Textile mill, whose cinogen at levels much below those workers' health experience served as which will produce asbestosis. Two bash for the current British standard.. surveys of shipyard workers who had "Of significant importance, new dam x-ray evidence of pleural plaques, but have recently been made available con generally not of pulmonary fibrosis, . ceniing the cancer risk of workers at foe showed a 2^5-fold excess risk of death textile mill reviewed for the British from lung cancer and high risk of standard, including those workers first mesothelioma.** . ' employed after 1933. It was found that ' - Finally, a recent study by NIOSH there was excess mortality horn hihg- was reviewed which showed that the . cancer among .those workers who en mortality experience of underground tered scheduled areas after I January metal miners exposed to asbestifoita 1933. There was clear evidence of minerals produced a threefold in some- excess of lung cancer and res- .' creased risk ofbronchogenic carcinoma pinuory deaths among those first ex- ' in workers. Fiber concentrations in the .-posed between J933 and 1930. Equally-. - mine, average 0.24 Veal. - . important was foe finding that there still ~ ~:j. In discussing considerations applic appears to be an excess of deaths due to - able to. standards for carcinogens, lung cancer after 13 or more years'ex OSHA stated that, "In the case of as posure even among those, first exposed' - bestbs, we are dealing with a substance'.. in 1931 and subsequently. Indeed, it is . that poses a range of health risks to the ^known that mesothelioma deaths hare - -working population. These include the ^tccurred among the specific group of; threat of cancer; as well as asbestosis/;. -290 workers whose experience prior to . In considering the controversial issue of 1966 had led to the development of the-:;/carcinogenicity, OSHA is relying upon 'A.- current standard, as detailed above.*'- not only the new data reviewed, above, -^Additionally, they acted the increase - bur the leading scientific principles and occurrence of mesothelioma in workers -' /options believed to reflect (be research ' only indirectly exposed to asbestos,. ; conclusions of international cancer ex perts, which were developed since at not known to OSHA at the rtma that the original standard was promulgated. "A. THE LATENCY CARCI NOGENIC EFFECTS "In humans, the latency period for chemical carcinogens may well extend between 20 to 40 or more years. Analogous periods exist for test ani mals. This means that the disease may undergo a long development before a tumor is actually detected. At that point, it has, reached a stage where re moval of the worker from the work place may be of no avail and where treatment may be extremely difficult If not futile. Prudent policy would there fore seem to indicate that every reason able measure should be taken to elimi nate human exposuit to chemical com pounds as soon, as their carcinogenic nature is identified. "B. variability IN INDIVID UAL SUSCEPTIBILITY IN RELAHON TO THE CONCEPT OF A THRESHOLD "Cancer development may be influ enced by such factors as the differing susceptibiltry of various body organs. In animal studies, ir has been found that individual -variability in a response to carcinogens- is great, depending upon factors such as age. sex, hormonal status, diet, and generic factors. Thus, in. the- working population, certain, groups, such as those already biologi cally compromised, may be more sus ceptible dun other groups. , ` . "C. A 'THRESHOLD! LIMIT . ' "Because of the variability of indi vidual response to carcinogens and other factors, the concept of a do effect or threshold level may have little real significance on the basis of existing knowledge.. While some.level, below whkb exposure to'a carcinogen does not cause cancer, may conceivably exist for uiy ope individual; other indi viduals in foe . working population may have cancer induced by doses so low as to be effectively zero; This is not to say that' researchers will never find a threshold level for a carcinogenic sub stance;- but !jt does mean thatihethresbold concept for carcinogens is, at present, more a manor of responsible regulatory policy than a precise, scien tific determination.-- *: -.- . *` These theoretical concepts hive a .//Continued on paged' UCUIUIllQ va. . . Spackie Material Continuedfrom page 3 Should.be Limited Consumedfrom page 2 bearing on the asbestos issue, particu Act requires that the Secretary establish larly as to the question of the existence, standards to extent feasible, and there rtfaeir own trades. The arcs should be or nonexistence, of a threshold level of fore the Secretary must mire foio con cleaned, preferably with A vacuum, U carcinogenic effect. A no effect level sideration technological and economic soon as the dust has settled. If no vac* theoretically may exist, but it has not factors. Him is available', the floor should be been demonstrated. "OSHA believes that it may be ap dampened prior to sweeping, and the "In previous rulemaking proceed propriate to postpone the effective sweeper should wear a mask. ings, OSHA has considered these is of the proposed exposure level Wauw Hea*lth Effects Seen " ' . 1 i .* ' sues aod determined that in the absence of the existence of problems of feasibil of evidence to establish a safe level on ity of a technological and economic na Simply because sanding is only a the basis of present knowledge, n- ture.. OSHA expressly invites com small pan ofthis consrroction activity is ployec- exposure must be reduced as ments on this issue, including comment do reason to minimize the importance low as feasible.'*- . " on the appropriateness of a phased of the problem. Although exposure du In a further, discussion of the major schedule for compliance with any new ration may be short, the cumulative ef jprovisions of the proposed standard, exposure leveL, based on such feasibil fect ofrepeated short-term exposures to OSHA explicitly recognized that, ity factors, hr this respect, OSHA par measurable concentrations of asbestos fibers can be serious. In the course of a "since the promulgation of the current ticularly invites comments on the struc standard, several distinguished indi ture of the asbestos industry generally medical study of 69 diywall tapers be viduals anti many agencies, both public including factors distinguishing par longing to Local 1974 of the Drywall Tapers and Painters of Greater New York, two-thirds of whom had had an exposure often years duration or longer and 61 of whom were smokers or ex and private, have made valuable con tributions to the field of toxic sub stances generally, and asbestos spe cifically. '`Erasure Levels. Recently, the ticular sub-industries in terms of meth ods of asbestos use and capabilities of compliance." The deadline for submission of comments on the proposed regulations smokers. X-ray abnormalities charac --National Institute for Occupational is December8, 1975. teristic ofasbestos exposure were found Safety and' Health (NIOSH) has in Additional provisions in the proposal in 37 out of 63 films. There is a close formed OSHA that it is currently re- . put forth by OS HA would "extend the similarity between these findings and [ viewing data which may provide signif- retention period for medical and' those among insulators. I team information with respect to the monitoring records to forty yean, or for At least, one brand of commercial wallboaxd finishing compound- is cur rently available containing no asbestos. It is likely that, as the negative aspects margin of safety afforded by the exist ing asbestos exposure limits. In a memorandum dated 29 September 1975 to the-Deputy Assistant Secretary the duration ofemployment plus twenty yean, whichever is-longer; provide procedures, for the transfer of medical and monitoring records of certain' of asbestos-containing compounds be of Labor for OSHA, the Director of . former employers; require specific min-.. come more widely known, other man NIOSH stated; . imiim data on medical and monitoring ufacturers will develop new formula tions that are-free of asbestos. Until then, only premixed materials should be used and the sanding of dry material eliminated or reduced as much as pos sible. . . _____ Multiple and consistent epidemiclogical studies leave virtually no doubt that asbestos is carcinogenic, to man. . - records; revise the procedures for initial and subsequent monitoring; modify the / definitions of asbestos and asbestos fiber; add provisions for employee - "OSHA also believes sufficient .hygiene, information and training; re- ." medical and scientific evidence-has - * vise and update the requirements- for' now been accumulated to warrant the ' respirators, and warning signs and' designation of asbestos as a human car- labels; and establish a time parameter emogen. Therefore, it is incumbent for sampling ceiling concentrations. In . ; upon OSHA to propose tbe establish- - addition, the proposal will suggest meat of safeguilds to protect the lives work practices to be followed for cer- of affected workers. . tain operations and processes involving . No Safe Level for a Crrefoogeri "OSHA deems it appropriate .to . posal that would add sputum cytology-' propose that the 8-hour exposure limit " as a diagnostic test. This is proposed-^- (TWA) be lowered to 500,000 asbestos - only for workers who are forty-five. fibers per cubic meter (0.3 asbestos fib-. , years old. or who have been employed:, as per cubic centimeter), and that the v~ fo the asbestos trades for ten years or ' . ceding exposure limit be 5,000.000 as- '. more. Here, analysis of cells coughed* bestos fibers per cubic meter (5 asbes- f up from tbe lung may be useful in fodi-1, tos fibers per cubic centimeter) for anyj-Tt eating the early stages oflung cancer, at*l period up to 15 minutes. OSHA recQg-~~~r a point where more successful treat-j- - nixes that there is no assurance of a safe '*- ment can be accomplished. This proce- ' exposure lor a suostaace with known - dure was tecendy proposed to NIOSH cafempgrruc^^prenrrfy- 'in this case as-'- by President Haas, for all members of . bcstoC and thus there he no de. -^the IAHFIAW and is befog considered u tcctabic concentrations-- However, the -`by the Institute.' - '- ` ` ; **'