Document xzdGbxxM2dqd7V324bbjrMbo0

RI KER LABORATORI ES. INC. Interoffice Correspondence: July 6, 1979 cc: F. D. Griffith TO: R. A. Nelson FROM: M. T. Case SUBJECT: Fluorochemical Chronic Toxicity In my response to Drs. Hodge and Mitchell recommendations, I strongly recommended that a chronic rat study on a fluorochemical be started as soon as possible. At that time FC-807 was indicated as my choice but in view of the fact that given the very low potential human exposure via an indirect food additive the FDA would not ask for carcinogenicity data, the decision not to proceed with the FC-807 study is understandable. As I sat listening, several weeks ago, to both John Favorite and Tom Scheuerman talk about being responsible 3M scientists in the area of toxicity testing, I was reminded of the lack of chronic toxicity data on 3M fluorochemicals. I believe it is paramount to begin now an assessment of the potential (if any) of long term (carcinogenic) effects for these compounds which are known to persist for a long time in the body and thereby give long term chronic exposure. Over a year has passed since the completion of the IRDC 90-day rangefinder rat studies and to delay chronic testing any longer is not warranted. As I indicated before, I think that both the metabolic and chronic toxicity studies are important and must go forward. However, metabolic studies will not provide answers in the area of potential of any long term (carcinogenic) effects. In my opinion, 3M should have carcinogenicity data on at least two of its fluorochemicals and chronic rat toxicity studies need to be started soon - one yet in 1979 and the other in 1980. The 1979 study could be on FC-143 (we already have rangefinder information) - say at dose levels of 300, 100 and 10 ppm in the diet. /h 7 6 A M. T. Case MTC/sl O F S- 12 8 Made Available by 3M for Inspection and Copying as Confidential Information: Subject to Protective Order In Palmer v. 3M, No. C2-04-6309 3MA00593079