Document 70eyVgnv7ZMqpeopaeNwabqQj

BACK TO MAIN STABILITY IN WATER (HYDROLYSIS) TEST SUBSTANCE Identity: Remarks: Perfluorooctanesulfonate-potassium salt. May also be referred to as: PFOS, PFOS-potassium salt, 1-perfluorooctanesulfonic acid-potassium salt, or 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptdecafluorosulfonate-potassium salt. CAS: #2795 39-3. 3M production lot number was 171. Test substance is a light-colored powder at 25C. METHOD Method: Based on OPPTS: 835.2110 GLP (Y/N): No, but many GLP procedures followed. Year completed: 2001 Type: Hydrolysis as a function of pH Test sample preparation: Test solutions consisted of 1.0 mL buffered aqueous solutions at six pH levels (1.5, 3.0, 5.0, 7.0, 9.0, and 11.0). The resulting PFOS concentration in all test samples (sample triplicates and matrix spike samples) was approximately 500 mg/L. Samples were shielded from light during incubation at 50 for periods of 0 to 49 days. Control samples and blanks addressed potential non-hydrolytic degradation routes. Analytical Procedures: Samples were analyzed by quantitative HPLC/MS. Remarks: This study was conducted at 50C in order to facilitate hydrolysis. Rates derived at 50C were extrapolated to 25C by dividing by a factor of 10, which is valid for reactions with Arrhenius heats of activation near 18 kcal/mole. RESULTS Breakdown products: Not applicable. Degradation: The analytical results indicate no degradation of PFOS or dependence on pH. The mean and standard deviation of all observed PFOS concentrations, pooled over the six observed pH levels, indicate that the pseudo-first order hydrolytic half-life of PFOS is greater than 41 years. CONCLUSIONS The analytical results indicate no degradation of PFOS or dependence on pH. The study indicates that the hydrolytic half-life of PFOS in water is greater than 41 years. 1 BACK TO MAIN Submitter: 3M Company, Environmental Laboratory, P.O. Box 3331, St Paul, Minnesota, 55133 DATA QUALITY Reliability: Klimisch ranking: 2 Remarks: Study was well conducted, though not under GLP. REFERENCES This study was conducted at the 3M Environmental Laboratory and Pace Analytical Services, Minneapolis, MN under Lab Request Number W1878. See 3M Environmental Laboratory Report No. W1878 (dated March 27, 2001). OTHER Last Changed: June 21, 2001 2