Document 3e4GoZ89VmYzKLMxab9aB4RmO

Katherine E. Reed, Ph.D. Staff Vice President 3M Environmental Technology and Safety Services g&W- U02.-00375 go'373 CERTIFIED MAIL October 30, 2002 Contain 900 Bush Avenue Building 42-2E-26 PO Box 33331 St Paul, M N 55133-3331 651 778 4331 AK&S.6- II3S CBI Document Processing Center (7407M) EPA East - Room 6428 Attn: Section 8(e) Office of Pollution Prevention and Toxics US EPA 1200 Pennsylvania Ave., NW Washington, DC 20460-0001 r-o TSCA 8(E) SUBSTANTIAL RISK NOTICE ON: Perfluorohexane sulfonate potassium salt Reference 8EHQ -1180-373, 374 Dear Sir: 3M recently sponsored an "Oral (Gavage) Combined Repeated Dose Toxicity with the Reproductive/Developmental Toxicity Screening Test" Study of perfluorohexane sulfonate potassium salt (PFHS), T-7706. The study was conducted at Argus Research Charles River a Laboratories, Horsham, Pennsylvania. The preliminary draft results include certain findings s that appear appropriate for TSCA section 8(e) submission. --acmo -- irn Parental male rats were dosed for at least 42 days. Parental females were dosed for approximately 60 days. No PFHS related effects were observed in the parental females. The adverse effects noted in parental male rats exposed to PFHS included: (a) an increased absolute liver weight; an increased liver-to-body-weight ratio; and a liver-to-brain-weight ratio for both the 3 and 10 m/kg/day doses; (b) decreased average values for cholesterol in the 0.3, 1, 3 and 10 mg/kg/day doses; (c) decreased triglycerides in the 10 mg/kg/day dose; (d) minimal to moderate enlargement of centrilobular hepatocytes in the 3 and 10 mg/kg/day doses; and (e) increased incidence of thyroid follicular cells hypertrophy and hyperplasia in the thyroid glands of males in the 3 and 10 mg/kg/day doses. There were no signs of neurological, developmental or reproductive effects. op5 oC cCnO A copy of this study report will be sent to EPA when received. A previously reported Exploratory 28-day Oral Toxicity Study conducted with PFHS, among other compounds, demonstrated some of these same adverse effects. See Letter from 3M to 8(e) Docket, August 21, 2000 (requesting this and other studies to be moved from AR-226 to the 8EHQ -1180-373, 374 docket). jy EPA'OTS 000811850N 0Q06115QN I Office of Pollution Prevention and Toxics Page No. 2 October 30,2002 Please contact Dr. John Butenhoff, 3M Corporate Toxicology and Regulatory Services, 651-733-1962, for further information. Sincerely. Katherine E. Reed Staff Vice President, Environmental Technology and Safety Services