Document rxOr9dXnNqjM0J4NJKMqRDjjr

E. 1. du Pont de Nemours & Company WILMINGTON. DELAWARE 19698 CZNTXAL ACSCAhO-COePAATMCNT ana Development KASKZLL LIO*TOY TOXICOLOGY ANO INDUSTRIAL MEOICINI -- cc: M. 3ranan, PIT, N-65 37 .ary /J. A. Zap?, Zr. -Ullt 6, 1975 J. V. AZAMS ENGINEERING DEPT. L-33WS' ASBESTOS FIBER IK -OOP GRADE ADIPIC ACID Rf*.: Leecer, J. W. Adams co C. F. Reinhardt, 6/2/75 Lactar, V. M. Branan to C. F. Reinhardt, 6/4/75 In the first referenea latter, some quantitative aspect* of the u*e of a*bastos gaskets in fluid bad coolers employed in the pro duction of adipic acid era described. The small area of gasket la potential contact with the acid (525 sq. in.) and the large processing rate (35,000-50,000 pounds per hour) of the acid itself have Led you co the conservative assumption chat the resulting product could con tain 2 ppa asbestos. Basad upon eha data submitted, I do not believe the potential praaanea of such a small amount of asbastoa in tha adipic acid presents a toxicological problem. When the portal of entry of asbestos into Che body is tha lungs, a toxicological problaa has been demonstrated. k recent publication by P. Gross at al. [Archive* of Environmental Health 29 3^1 (1974)] Indicated chat tha ingestion by rata of a diet containing as much as 51 asbestos over most of their life did nee produce cancer. Thie, la addition to ocher similar experiments reported in tha lama article, indicates that Ingested mineral fibers, including asbastoa, do not present tha hazard that has been associated vlth tha Inhalation of some mineral fibers. However, since you state chat the theoretical 2 ppm level of asbastoa in tha adipic acid may In raality ba on tha high aide, it may ba prudent to obtain analytical data on the exact amount of RS/ms ORAL TOXICOLOGY SECTION DUP 0903570 scttcr tminos 0" bctter uvinc . . - rnmouon cnbmistsv DU 024972