Document xVOv419OQDJaXb4b4wE09LJg

f /C\ \.v THE MOUNT SINAI MEDICAL CENTER ONE GUSTAVE L LEVY PLACE NEW YORK. N Y 10029 Mount Sinai School of Medicine The Mount Sinai Hospital 7 1914 * Seifacft Laboratory John A. lfoora, BVM . .' Cimmingt Bute Sctmctf Building u 1 V IP Butt 102 Strutt NtwYttk.Ntw York 10029 Aatlatest Adalnlatrator for Peatleldea f} it tnfSJ2> *30*173 and Toxic Substances Environmental Protection Agency mi.. m ^ . *17 b.t Tower - T*7*S *01 M ltrt, l.W. ~ Ja Washington, D.C. 20460 *" * Dear JDt. Moore > It has been Bade known to me that my written reaarka of October 11, 1904 concerning the Watural Keaourcea Defense Council's Petition for a "Prohibition on Continued Use of Asbestos In Automobile Brakes" will enter, with other documentation, into the rule-making docket along with the original petition. I am therefore requesting that this letter be substituted as a formal critique. . My concerns regarding the petition are many, essentially focusing on lack of Insight and on an unseholarly approach to the problemt - The HIDC claims that both epidemiological and pathological reports "have shown only recently that asbestos la one of the largest alngle causes of environmental human eancer In the United States." This statement does not accurately reflect the literature. In support of this statement the petition cites IBS Secretary Califano who reported that approximately 171 of American cancer deaths over the next several decades will be "linked" to a'sfcestos. There are approximately five hundred thousand cancer deaths per year In the United States which would roughly translate into 85,000 cancer deaths per year "linked to asbestos." Xnsedlately following this statement Is an attribution to Mieholson and co-woTkers who have estimated that cancer deaths in the United States from asbestos will number some 6,500 to 10,000 per year over the next 20 years. The authors of this document fail to reconcile this order of magni tude difference In these figurest fall to resolve the proportion of excess cancers attributable to workplace exposures! have not considered that If 8,500 cancer deaths will occur among 10-15 million "exposed" workers In different occupational settings, $5 thousand asbestos "linked" deaths means that everyone In the general population la at the same level of risk. It seems farfetched; - Jj their discussion of mesothelioma and lung eancer, the RDC authors use data from studies of Insulation workers In their descrip- \ UCC 004206 John A. Moore, DVM .2 Dteuber 7, 1984 tlon of Iseruitd risk of asbestos diseases in exposed populations. The nature of the fiber exposure, fiber type, fiber dimensionality and fiber concentration are significantly different when compared to workers maintaining and repairing brake pads. Data for insula tion workers may have little bearing for brake workers. These ._4sta *rt vBcrltically accepted as data applicable for all workers ~exposed to any variety of asbestos fiber; The assertion that all asbestos fiber trues are carcinoeenlc In humans Is correct, lowever, mot all fiber types produce human mesothelioma fnp -- iothalloasi hiv baan rmportmA exposed to anthophylllte fiber in the workplace) and not all of the asbestos fiber types produce the same attack rates for broncho genic carcinoma. While It is true that the three major varieties of asbestos used in the United Stetes induce both types of malignant tumors in experimental animals, industrial manipulation may alter outcome; " There is an attribution to a study conducted by ay colleagues here in the Invlronaental Sciences Laboratory which revealed excess cancer mortality Nln workers with short-term exposure-one month or less of employment in an asbestos plant.** This citation appears at the and of a paragraph which states that "People living in the area of asbestos mines, mills, factories and even shipyards and family members of asbestos workers have become victims of mesothelioma despite what we would be considered light exposure to the dust.** The asbestos plant in Paterson, dev Jersey is believed, by many (Including Seidman of the American Cancer Society) to have bad workplace exposures approaching lOOf/ml. Vieholson occa sionally uses a figure of 35, I have used a figure of 50 but It is generally coneeded the exposure levels were very high Indeed. One month's exposure during the eeeond World War translates into a 500-1,OOOf/ml exposure day (10-hour ehifts during the second World War). Using a 20-day work month this computes to a 10,00020,OOOf/ml exposure month. This would correspond to approximately a 2-5 year exposure In the occupational setting at the present 2f/ml level. Vo one would consider this a "trivial" exposure. Wo one would consider this a ^bystander" or "environmental" exposure; - In the very next paragraph, on page 8 of the petition, the work of Harries, carried out In the Devonport shipyards of Great Britain, is used to support their argument that mesothelioma may occur from "bystander" exposures. Harries and colleagues shoved that the tearing out of asbestos fiber on shipboard results in aerosols which may approach 1,OOOf/ml in the immediate environment 1 Fiber measurements made during tear-out operations, aboard ship, haveshown tens of f/ml of air in areas removed from the actual site of rip-out. Again, this Is included to support the argument of the petitioners that "indirect occupational exposure" was sufficient to produce mesothelioma many years later. These indirect measurments are considerably greater than those encountered In most workplaces today. Additionally, the fibqr types encountered in UCC 004207 m mi * John A. Moore, DVH keraber 7, 1984 tilt Paterson intoletIon plant was amosite and the fiber encountered by Harriet in the Devonport shipyard vat predominantly crocidolite. The mesothelioma frequency for both theta fiber types exceed* thoae reported for ehrytotile in every study the vorld over. We are dealing with wesotheliowarisk for different fiber typet. (Although ehrytotile atbettoa doet produce human mesothelioma one cannot nee the experience -of workers exposed to crocidolite and aamsite as a "measure of risk for ehrytotile expoturei" * Although esbestot fiber released from automobile brakes may Increase the asbestos levels encountered in urban air the report of a mesothe lioma in a toll collector is not evidence of an etiological associa tion; - I will support the contention of the petitioners that there are operations encountered during brake maintenance and repair which release "dangerous levels of asbestos during brake servicing;" ~ The general case for risk to non*occupatlocally exposed persons is based on risk assessment models. For example, Richolson (1983) has provided the gnvironmental Protection Ageney with a document entitled "Asbestos Health Effects Dpdate." Using this model a general scenario is generated for both lung cancer and mesotheliosut and extrapolations are made concerning risk to populations for which no exposure data exist. Sleven studies provide lung cancer data whereas four studies provide the mesothelioma data base. The lung cancer studies provide fractional Increases of lung cancer risk per nnlt of exposure but these fractional risks vary consider ably depending on fiber type and industry, go it is with the mesothelioma data set which is based on a number of fiber types integrated to yield a single r.lsk model. The question to be raised is whether data for crocidolite, amosite and mixed fiber types (the insulation worker data) may be used for chrysotile. This, coupled with the relatively poor workplace fiber measuresttnts, yields a model which may be used only in its broadest context. These shortcomings were raised in a recent MIC document (1964) where rentes of risk were provided rather than a single value. Again, the mesotheliosu data Cl stress mesothelioma because segments of the population will live long and this will be the important disease on the basis of time) is based on insulation workers (mixed fiber), chrysotile textiles, amosite insulation, and asbestos cement product manufacture. The lowest values exist for chrysotile exposure in textile plants. Therefore, all of the asbestos deaths projected into the fhture are based on risk assessment for mixed fibers in a range of circumstances. The variance associated with these projections are large. The numbers of deaths attributable 1 to asbestos brake pad maintenance amounts to some 500 par year \ over the next several decades. This value may be lover or even \ greater than given. We simply do not know; . - The only pleural mesothelioma described in a brake repair worker, la which only chrysotile asbestos fiber was observed in the pulmon- UCC 004208 ti ^878 j: * John A. Moore, DVM 4. December 7, 1964 Ary tissues, was reported by myself. 1 believe this working popula tion to ba at risk but I also believe this risk to be lass than encountered with other fiber types in other work environmental Where are the data to show that substitute frletion product Materials are "safe"? What happens to e.g., araaid fiber when sheared from a brake surface? i ** f j, - Why is "sintered ^etal" compositions considered safe? Sintered hard aetal materials are now implicated in pulmonary disease (hard- metal disease). * I agree with the petitioners that there are many instances where brake maintenance and repair subjects workers to asbestos fiber exposure which increases their neoplastic risk. There is no question that this occurs and that the risk is measurable. 1 similarly believe that there are no date to support that such risk exists for the general population, txposure to the general population may oceur and that the control of asbestos emissions should be instituted. However, we have no data to support the contention that it represents a "public health haxard." 1 believe it would be prudent to prevent such exposures from occurring to the general population even though there ere no data to support that such exposures are hasardous. The federal courts have noted that one may rely on "general data" in making certain decisions. Therefore, If this petition is to be considered as a "general approach" to the asbestos problem then, presumably, the Bnvlronmental Protection Agency will base its decision on courtroom lav. As it now stands, one can only appeal for the decision to be based on the concept of "prudence" rather than science. The decision .should be made on the social basis and not a pseudo-scientific one. nils issue is a very important one and should not be approached in an uoseholarly fashion. My strongest objections focus on the misuse of data and the uncritical use of these data in supporting certain contentions. It is a form of quasi science which we, as environmental scientists, cannot afford or allow fo go unchallenged ec it reflects upon all of us and our work. * AMLijm bur M. Longer, Ph\ Associate Professor of Mineralogy. Associate Director, environmental Sciences Laboratory UCC 004209 C *879