Document 9154Zd4o0oN740Vevro8VwEN5

J rf 3M Katherine E. Reed, Ph.D. Staff Vice President 3M Environmental Technology and Safety Services I I3 900 Bush Avenue Building 42-2E-26 PO Box 33331 St Paul, MN 55133-3331 651 778 4331 nimzu 99z. Certified Mail F e m } . 0 3 0 3 - 003>15 May 16, 2003 S eih? - ^ 0 -3 .7 3 Document Processing Center EPA East - Room 6428 Attn: Section 8(e) Office of Pollution Prevention and Toxics US EPA 1200 Pennsylvania Avenue NW Washington DC 20460-0001 S IOS m ' PO 7 0 CO "SfTJ 33 S r?! oO CO RE: TSCA 8(E) SUPPLEMENTAL SUBMISSION: Docket No. 8EHQ-0602-00373 000811855S Dear Docket Coordinators: OODflllfiSSS 3M has previously informed the EPA (May 29, 2002) of the results of a rat 28-day oral gavage study with triphenylbenzyl phosphonium cation/N-methyl perfluorooctanesulfonamide salt (TPBP C8 amide; PMN 88-141) that indicated hepatic toxicity. In today's submission, 3M provides results from ecotoxicity studies conducted on TPBP C8 amide. Notox Safety and Environmental Research conducted a 96-hour acute toxicity study in zebra-fish (Danio rerio), an acute toxicity study in Daphnia magna, and a 96-hour fresh water algal growth inhibition test. Preliminary results indicate that the acute EC50 value for zebra-fish is < 1.0 mg/L, the acute EC50 value for the algae Selenastrum carpicomutum is < 0.05 mg/L, and the acute EC50 value for Daphnia magna is < 0.05 mg/L. ro*o -Qrn ! '73o VJO 2o mo 3M believes environmental exposure to TPBP C8 amide is unlikely. The material is used as a fluoroelastomer curative at concentrations less than 5% and is entirely mixed with the fluoroelastomer gum. The customer cures the fluoroelastomer mixture to form final articles (such as o-rings, and hoses) at high temperatures. By the end of the curing process, the fluorochemical part of the complex covalently bonds to the polymer backbone and the phosphonium cation thermally decomposes to triphenyl phosphine oxide and toluene. Based on our knowledge of the manufacturing processes and downstream uses of the material, the only potential pathway for release of the chemical appears to be through the air. 3M believes that the material is not released to the air, however, because it is not volatile and because air testing conducted during of the cure process forming the final article did not detect the TPBP C8 amide. I Document Processing Center Office of Pollution Prevention and Toxics Page No. 2 May 16, 2003 A copy of the final report will be forwarded to EPA when received. Please contact Susan Beach (651-778-7452) if you have any questions or if we can provide additional information. Sincerely, Katherine E. Reed Staff Vice President Environmental Technology and Safety Services A