Document EvNQmeQ61OR8GGJdgZ4NJYr6x

Subject: RECEIVED FEB 2 8 1986 INTERNAL RECOMMENDATION AND/OR AUTHBB^Xpi ___________________________________ ______________________________________ Page: NEED FOR RESPIRATORS E. E. WANG'S LETTER OF 2-18-86 Date: 2-25-86 Explanation: I very much disagree with the requirement that "all plant workers exposed to the asbestos environment (in our case, everyone), regardless of the current airborne asbestos concentration are required to wear their suitable respirators". First and foremost, the recommendation made by the California Air Resources Board was questioned by AIA/NA (copy attached) as well as the State of California. It is my understanding that when thi-s proposal was reviewed by higher officials in California they also questioned some of the data and the Board was instructed to review pro cedures and "facts" and answer some questions prior to continued review of the proposal. I personally disagree with this assessment and requirement. It appears to be in line with the normal over-reaction of people who have not been well trained in the history and studies of asbestos fibre. One must first note that asbestos is a natural element and in some areas exposure naturally exceeds our plant exposure levels, with no increase in asbestos-related disease. If this is a Corporate decision, how do we enforce the rule? Denison has been to court several times to stop smoking on plant property, and as you know, we were only able to restrict the smoking areas. Respirators are at best a very objectionable item to our employees. I feel that this rule would be challenged and without any factual reason to require respirators, we would lose. If we are going on the assumption that a threshhold exposure level must be established before any exposure can be allowed, we need to put everyone into a totally clean FEB. 28 1986 J-M Manufacturing Co., Inc. Internal Correspondence To : All Plant Managers From : E. E. Wang, Stockton H.Q. Date: February 18, 1986 Copies : C. J. Chen, Wilfred Wang Subject : ASBESTOS THRESHOLD EXPOSURE LEVEL Asbestos is a known animal and human carcinogen. It has been listed by the U.S. Environmental Protection Agency as a hazardous air pollutant. The California Air Resources Board has recently recommended its listing as a toxic air contaminant. It should be further noted that there is not sufficient available scientific evidence to support the identification of an exposure level below which carcinogenic effects would not occur. Since no threshold exposure level (below which no significant adverse health effects are expected to occur) can be established, plant workers exposed to the asbestos environment (regardless of the current airborne asbestos concentrations) are required to wear .their suitable respirators all the time. D 002157 California Air Resources Board- Study Of Asbestos Emissions Draws AIA/NA Comments AIA/NA responded 'on Oct.- .18 to a California Air Resources Board (Board) staff investigation of asbestos emissions into the state's ambient air. The Board's determination could lead to the naming of asbestos as a toxic air contam inant (TAC). A TAC permits the Board and its local air pollution control districts to evaluate the need for, and appropriate degree of, controls for emission sources. Con clusions drawn in the staff report recommended the listing cf asbestos as a TAC, and treatment of it as a substance without a carcinogenic threshold. The thrust of AIA/NA*s comments were directed at both the risk assessment and the exposure estimates presented. High lighted are portions of the letter: "Although the California staff has drafted its own assessment of potential risks at various exposure levels, it has reached: conclusions that fall in the same range as prior risk assess ment authored by the Consumer Product Safety Commission, 002158 D t National Research Council and Ontario Royal Commission, as well -as Dr. Nicholson who has performed risk assessments for both E?A and OSHA. In each of these assessments, the same issues of choice of epidemiology studies, conversion of historical measurements to today's monitored exposures, determination of the shape of the dose-response curve, and consideration of fiber types arise. "A detailed assessment of these issues was contained in Dr. Kennv S. Crump's comments, on the OSHA/Nichoison risk as sessment. Dr. Crump is a recognized risk assessment expert who has often worked for EPA and OSHA. As Dr. Crump em phasizes in his report, each of the government risk assess ments, and for similar reasons California's new assessment, must be understood to be "upper limit assessments" because they: (1) Assume a linear dose-response relationship; (2) Assume.the same potency for all forms of asbestos despite significant data indica ting lesser potency for chrysotile, parti cularly, with respect to mesothelioma; and (3) Include within the calculated risk the substantial portion of the lung cancer risk attributable to cigarette smoking." "In addition, because.the California risk assessment is intended to predict risks at much lower exposure levels (0.C01 fibers/cc and lower vs. 0.1 fibers/cc and higher)than the OSHA risk assessment, even greater uncertainty exists that such upper level limit assessments are appro priate. In extrapolating risks to even lower levels than OSHA.extrapolated, considerable likelihood exisrs that the linear dose-response relationship overestimates human risk." "We also caution the Board against over-reliance on the expo sure estimates set forth in the'draft report. As the draft report acknowledges, no long-term asbestos sampling data are available and no method has been developed to extrapolate long-term average concentrations from limited short-term observations. "Despite those limitations, it is significant to note that the Beard's extensive monitoring program in fact found very little, ir any, evidence that the identified emission sources contributed to ambient asbestos levels. The very low. level of ambient asbestos found can be seen in two ways." "Accordingly, it would appear that the sampling study con firms that little reason should exist for concern about potential asbestos emission sources in California.. Even short term measurements in areas where asbestos emitters D 002159 might be expected to be most likely to be contributing to ambient exposures have not identified any significant con tributions to asbestos levels." The Beard responded by letter of Nov. 6 to AIA/NA and ac knowledged the limitations of their exposure estimates based or. the monitoring of local sites. However, the in tent, the Board asserts, was to document asbestos levels and the monitoring study accomplished this from their point of view. The Board referred AIA/NA's questions about risk assessment to the state Department of Health Services, which will issue a response at a later time. D 002160