Document vdNmvndr7kbVRNmXnDEzm3OR

January 3, 1968 George W. Wright, M. D. Head, Medical Research Department St. Luke's Hospital 11311 shaker Blvd. Cleveland, Ohio 44104 Dear George: As requested, I am sending, herewith, a copy of Paul's preliminary report on the feeding of chrysotile to rats. Best regards. Sincerely, deT:sld Enclosure cc-Dr. P. Gross Robert T. P. deTreville, M.D. ASARCO ALV 0002528 DATE: January 3, 1968 TO: Dr. Robert T. P. deTreville FROM: Dr. Paul Gross SUBJECT: Asbestos Feeding Study--Preliminary Report As part of our investigation of the bio-effects of asbestos, we prepared an intimate mixture of finely divided ballmilled chrysotile asbestos so that the chrysotile constituted 5 percent of the food by weight. This was fed to ten young growing rats for 21 months. A comparable control group of rats of the same age and weight was fed the same diet but without chrysotile. The weight curves of the two groups of animals were not significantly different from one another. At autopsy, 21 months after the beginning of the feeding experiment, no significant abnormality was found. Sections were prepared from various portions of the gastro-intestinal tract as well as from the heart, lungs, liver, kidneys, and spleen. Although all animals have not yet been processed, no abnormality has been found in the sections so far examined. P.G.-ejd P.G. ASARCO ALV 0002529