Document 719rbDNaEKkNEM2QJ37Mgd1je

A/C Pipe Producers Association 1400 Wilson BouUvord Suit* 1008 Ailinglon. -'Wginia 22209 <703) 841-1556 January 3, 1984 PLAINTIFF'S EXHIBIT BY HAND' Joseph A. Cotruvo, Ph.D. Director of Criteria and Standards (WH-550) Office of Drinking Water Environmental Protection Agency 401 M Street, S.W. Room 1111 East Tower Washington, D.C. 20460 Re: ANPR on National Revised Primary Drinking Water Regulations (WH-FRL 2418-1) Dear Dr. Cotruvo: The Association of Asbestos/Cement Pipe Producers (AACPP) appreciates the opportunity provided by EPA's ANPR to comment on the advisability of issuing a national primary drinking water standard for asbestos. AACPP has supported EPA's work over the past decade to develop the scientific data base upon which a rational decision can be made. Now that the compre hensive research program has been completed, the tentative mid1970's conclusions that asbestos in water poses no health hazard have been confirmed. Accordingly, EPA should close the book on asbestos in water, assure the public that it need fear no adverse health effects, and declare that a primary drinking water regulation for asbestos is unwarranted. As detailed in AACPP's attached comments, the research program of the past decade has laid to rest any prior doubts about public health risks of ingested asbestos. Numerous state-of-the-art animal bioassays, many of them conducted as part of the National Toxicology Program, have confirmed that even very high levels of ingested asbestos cause no adverse health effects, including cancer, in animals. Similarly, the many epidemiology studies of populations exposed for many years to relatively high concentrations of asbestos in drink ing water have typically found no increased cancer risks. Finally, continuing research has confirmed the unlikelihood that any significant number of fibers migrate from the \ ii CAPCO JEN 0024793 Joseph A. Cotruvo, Ph.D. January 3, 1984 Page Two gastrointestinal tract into gastrointestinal tissue where they might potentially pose carcinogenic risks. This sub stantial scientific data base confirms that there is no reason to believe adverse- human effects will occur from asbestos drinking water ingestion. The absence of any likelihood that asbestos ingestion will cause adverse health effects is further confirmed by the de minimis human exposures from United States drinking water. Monitoring data compiled by EPA demonstrate that all but a small percentage of U.S. drinking water contains asbestos concentrations below 1 million fibers/liter, which on a weight basis is roughly equivalent to 1 part-per-trillion. These very low concentrations -- significantly lower than any maximum contaminant levels ever set by EPA for other chem icals -- are due primarily to natural erosion, and prelimi nary EPA studies find such concentrations represent but a small fraction of total human gastrointestinal asbestos exposures. Given the overwhelming.scientific evidence that prevail ing levels of asbestos in U.S. drinking water will not cause adverse health effects, no recommended maximum contaminant level (RMCL) is warranted under the Safe Drinking Water Act. Any attempt to set an RMCL premised on the inconclusive results of the epidemiology studies of heavily inhalationexposed asbestos workers -- as recommended by the National Academy of Sciences -- would necessarily require ignoring the comprehensive ingestion epidemiology and animal data and be based on the most tenuous of unsupported assumptions. Consistent with sound interpretation of the relevant scien tific data base, EPA should follow no such course. Finally, even were there any reason to believe asbestos in drinking water causes health effects, neither monitoring nor treatment techniques are economically and technically feasible or generally available, as is required for drinking water standards under the SDWA. Not only is the only avail able monitoring technique, transmission electron microscopy, very expensive; but, its precision and accuracy, especially at the low asbestos concentrations found in most water supplies, do not meet acceptable criteria for legally enforceable stan dards. Only six communities throughout the nation treat CAPCO JEN 0024794 Joseph A. Cotruvo, Ph.D. January 3, 1984 Page Three drinking water for asbestos, indicating the absence of gen erally available treatment techniques. Moreover, the limi ted data from these facilities indicate such treatment is very expensive. No reasonable justification'exists for diverting scarce public resources from control of the many potential health hazards in drinking water to the monitoring and treatment of asbestos. AACPP therefore urges EPA to close the book on asbestos and declare in its next national drinking water standards proposal that no standard is warranted. The Agency should fulfill its obligation to assure the American public that it need not fear any adverse health effects from the prevail ing levels of asbestos in drinking water. Respectfully submitted. sdl Enclosure cc w/ enc.: Comment Clerk i CAPCO JEN 0024795