Document v1r181KDXan99ZRek5v31mOQZ

BACK TO MAIN STABILITY IN WATER (PHOTOLYSIS) TEST SUBSTANCE_______________ Identity: 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) Remarks: 3M production lot number 332. The test substance is a white powder at 25C. METHOD References: Based on OPPTS: 835.5270 and OECD Draft Document "Phototransformation of Chemicals in Water - Direct and Indirect Photolysis", August 2000. GLP (Y/N): No, but many GLP procedures were employed. Year completed: 2001 Type: Direct and Indirect Photolysis Light source: Suntest CPS+ or Suntest XLS+ lamp Light intensity: 680 w/m2 Wavelength range: 290-800 nm Duration: 69.5 to 164 hours Test matrices: Direct: Water (pH 7 buffered) Indirect: H9O?/water (1:1 molar equivalent) Soil/dilute aqueous CaCL solution (0.7 g/5mL) (3 soil types - loam, clay loam, sandy clay loam) Soil/dilute aqueous CaCl2 solution with H7O9 Fe2O3/water (Fe3+ at 24X molar excess) Fe9O?/water with ^ O ^ Commercial (Aldrich) humic material prepared as in OPPTS 835.5270 Each of the above direct and indirect test matrices included a series of unexposed controls (kept in the dark) for the evaluation of any degradation reactions occurring without the presence of light. Temperature: 253oC Test sample preparation: Aliquots of PFOA were added to three separate sets of VOA screw cap vials (exposed, unexposed, and control vials) containing 5 ml of appropriate matrix. Test vials were placed in the photoreactor. Control vials were wrapped in aluminum foil, sealed in a plastic bag, and placed in the photoreacter. Analytical Procedures: A UV/Vis spectrum of a saturated aqueous solution of PFOA was recorded between 190 and 110 nm. Samples were analyzed by quantitative LC/MS and GC/MS techniques. 1 BACK TO MAIN RESULTS Degradation and breakdown products: No conclusive evidence of direct or indirect photolysis of PFOA was observed under any of the conditions tested. Direct photolytic decomposition of PFOA was not observed based on loss of starting material, nor were any of the predicted degradation products detected above their limits of quantitation. There was a slight increase in perfluoroheptanoic acid concentration in the matrix containing Fe+3 and H2O2. However, this increase may have been caused by indirect photolysis of an unknown impurity in the PFOA test material. Data obtained from the Fe2O3 matrix samples (with and without H2O2) were pooled to provide sufficient statistical data to estimate the minimum half-life. The mean and standard deviation of these data indicate that the minimum environmental half-life of PFOA due to indirect photolysis at 25C is greater than 349 days. CONCLUSIONS No conclusive evidence of direct or indirect photolysis of PFOA was observed under any of the conditions tested. Data obtained from the Fe2O3 matrix samples (with and without H2O2) were pooled to provide sufficient statistical data to estimate the minimum half-life. The mean and standard deviation of these data indicate that the minimum environmental half-life of PFOA due to indirect photolysis at 25C is greater than 349 days. Submitter: 3M Company, Environmental Laboratory, P.O. Box 33331, St. Paul, Minnesota, 55133 DATA QUALITY Reliability: Remarks: Klimisch ranking: 2 Study was well conducted, though not under GLP. REFERENCES This study was conducted at the 3M Environmental Laboratory under Lab Request Number E00-2192. See 3M Environmental Laboratory Report No. E00-2192 (dated April 20, 2001). OTHER Last Changed: June 22, 2001 2