Document RJnVNy38JRgbNXyE4B5KwJ6Ma

BACK TO MAIN WATER SOLUBILITY IN NATURAL SEAWATER AND 3.5% SODIUM CHLORIDE SOLUTION - SHAKE FLASK METHOD TEST SUBSTANCE__________________________________ Identity: Perfluorooctanesulfonate; may also be referred to as PFOS or FC-95. (1-Octanesulfonic acid, 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8heptadecafluoro-, potassium salt, CAS # 2795-39-3) Remarks: The test substance is a white powder. Sample was recrystalized from a production lot of FC-95, and assigned a test, control, and reference number TCR 00017-046. Purity determined to be 97.9% by LC/MS, 1H-HMR, 19F-NMR and elemental analyses techniques. METHOD Method: Based on OECD 105, OPPTS 830.7840. GLP (Y/N): Yes Year completed: 2001 Water Sources: Natural Seawater = Ocean Scientific, lot # LN 58, salinity = 3.5% Sodium Chloride = EM Science, 99% pure, mixed with ASTM Type I water to achieve salinity of 3.5% Remarks: The definitive test consisted of placing an excess amount of test substance with the appropriate water in centrifuge tubes. The tubes were vortexed and shaken at 150 rpm at 30C for 24, 48 and 72-hours followed by 24-hours of equilibration at 22 - 24C. Following equilibration, samples were centrifuged and the supernatant was analyzed by high performance liquid chromatography with mass spectrometric detection (LCMS). RESULTS__________________________________________________ Natural Seawater: 3.5% NaCl Solution: 12.4 mg/L at 22 - 23C 20.0 mg/L at 22 - 24C Description of solubility: Slightly soluble. The 24, 48, and 72-hour solubility concentrations were averaged to obtain the overall mean solubility concentrations for the natural seawater. The 24-hour values were not included in the mean solubility of sodium chloride BACK TO MAIN calculation because when the coefficient of variation was calculated for all of the replicate analyses for that day, it was > 15%. CONCLUSIONS______________________________________________ The overall mean solubility concentration of the test substance in natural seawater it was 12.4 mg/L and in a 3.5% NaCl solution it was 20.0. PFOS solubility decreases with increasing ionic strength of the medium. Submitter: 3M Company, Environmental Laboratory, P.O. Box 33331, St. Paul, Minnesota, 55133 DATA QUALITY______________________________________________ Reliability: Klimisch ranking 1. REFERENCES Studies conducted at the 3M Company, St Paul, MN, 2001, Environmental Laboratory Project Number EOO-1716. OTHER Last changed: 6/26/01