Document ZndjJG3zBg1rmK0pydBdQnVQ7

BACK TO MAIN STABILITY IN WATER (HYDROLYSIS) TEST SUBSTANCE__________________ Identity: Remarks: Perfluorooctanoic acid, ammonium salt; may also be referred to as PFOA ammonium salt, Ammonium perfluorooctanoate, FC-116, FC-126, FC-169, or FC-143. (Octanoic acid, pentadecafluoro-, ammonium salt, CAS# 3825 26-1). 3M production lot number was 332. Test substance is a white powder at 25C. METHOD Method: GLP (Y/N): Year completed: Type: Based on OPPTS: 835.2110 No, but many GLP procedures followed. 2001 Hydrolysis as a function of pH Test sample preparation: Test solutions consisted of 1.0 mL of buffered aqueous solutions at six pH levels (1.5, 3.0, 5.0, 7.0, 9.0, and 11.0). The PFOA concentration in all test samples (sample duplicates and matrix spike samples) was approximately 5154 pg/L. Samples were shielded from light during incubation at 50 for periods of 0 to 109 days. Control samples and blanks addressed potential non-hydrolytic degradation routes. Analytical Procedures: All samples were analyzed using HPLC/MS. Remarks: This study was conducted at 50C in order to facilitate hydrolysis. Rates measured 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 for pH = 3.0 and pH = 11.0 failed to meet the data quality objectives and were rejected. Data from the remaining four pH levels indicate a small, pH-independent loss of PFOA. Pooled over pH levels, the measured PFOA concentrations provide the following two estimates of the pseudo-first order hydrolytic half-life of PFOA. 1 BACK TO MAIN RESULTS (Continued) Analytical Method/Quantities Employed Least Squares Log-Concentration Slope Estimate Concentration Mean and Standard Deviation Hydrolytic Half-Life at 25C (years) > 92 > 97 CONCLUSIONS Based on the experimental data, the hydrolytic half-life of PFOA is estimated to be greater than 92 years at environmentally relevant conditions. 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 under Lab Request Number E00-1851. See 3M Environmental Laboratory Report No. E00-1851 (dated March 30, 2001). OTHER Last Changed: June 21, 2001 2