Document RaMdbJMx615g3RjN7GaewrxRV

E. I. DU Pont de Nemours & Company WILMINGTON, DELAWARE 19898 EMPLOYEE RELATIONS (DEPARTMENT 10:' US 'TOT 10: amt- February 4, 1985 L. T. FREELAND POLYMER PRODUCTS DEPARTMENT BEAUMONT ASBESTOS CEMENT (AC1 PIPE FOR WATER LINES This confirms our recent telephone conversation in which I indicated that the Safety and Occupational Health Division recommends that no new AC pipe be installed for potable water. Some pertinent information which we recognize in making this recommendation is Municipal water systems already contain a lot of AC pipe. A 1981 American City and County water main pipe survey reported that the proportion of AC pipe in place was 13.9 percent in 1980. It was estimated that 40 percent of pipe installed in 1980 was AC. The American Water Works Association standard permits the use of AC pipe except for water which is highly corrosive toward AC. Corrosivity is measured by a "aqgressivity index" which is a function of pH, total alkalinity and calcium hardness. However, some studies have indicated tfyat the AI is not appropriate for predicting fiber release from AC pipe because other factors, e .q., iron, silica, manqanese and zinc may contribute some protection against corrosion. Deteriorated AC pipe has been found in some municipal water mains. In at least one case, a scraping procedure used to clean the pipe interior DUP 0908885 SC-DP-08050 qreatly increased the fiber count of water trans mitted throuqh the pipes. . Drilling and tappinq AC pipe can introduce asbestoscontaining debris into a pipe unless fraqments are flushed out under pressure. Flushing water mains containing AC debris can cause unusually hiqh fiber counts. Eventual dismantlement of deteriorated AC pipe will require special handling precautions. Peer reviewed animal studies do not at this time support an association between inqested asbestos and gastrointestinal cancer. Epidemioloqic studies are equivocal. For example, the National Academy of Sciences (NAS, 1983) in the draft report entitled, "Nonoccupational Health Risks of Asbestos Fibers" stated: Because of limitations inherent in the size of exposed populations, the duration of exposure and the lack of individual exposure data, it has not been possible to determine whether or not there is an association between gastrointestinal cancers in humans and the presence of asbestiform fibers in drinking water. However, the Royal Commission on Matters of Health and Safety Arisinq From the Use of Asbestos in Ontario (1984) stated: After reviewing all the available medical evidence, the commission con cludes that eating or drinking asbestos in the concentration currently found in drinking water, beverages, or food in North American is not associated with any significant increase in disease. Many studies have looked for a relation ship between oral ingestion and disease, but so far the results are negative. EPA recommends that AC pipe not be used for potable water mains and has sent a draft regulation pro hibiting this to the Office of Management and Budget for approval. Good substitute materials are available. Depending on circumstances, Enqineerinq Department personnel recommend reinforced concrete, concrete-lined steel or PVC pipe. DUP 0908886  Even though AC pipe for potable water lines has not been proven to be detrimental to health, we recommend that it not be used in new installations because of the employee relations, public relations and eventual handling problems involved. SAFETY AND OCCUPATIONAL HEALTH DIVISION ( J. R. Martin, Survey Supervisor JRMimmv DUP 0908887 3