Document 3Qeg0y5aZLQ1KVkB2V873dgoy

ACTIVATED SLUDGE RESPIRATION INHIBITION TEST 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 taken from 3M lot number 217. Sample was stored under ambient conditions prior to testing. Purity determined to be 90.49% by LC/MS, *1H-HMR, 19FNMR and elemental analyses techniques. METHOD Method: OECD 209 Test type: Static acute GLP: Yes Year Completed: Study completed 1999. Report completed 2000 Analytical monitoring: Dissolved oxygen concentrations. Statistical methods: Probit analysis using the computer software of C.E. Stephan. Test organism source: Activated sludge collected from the Prospect Bay Wastewater Treatment Facility, Grasonville, Maryland. Test conditions Dilution water: NANOpure Synthetic Sewage: 1 liter municipal water 16.0 g peptone 11.0 g meat extract 3.0 g urea 0.7 g NaCI 0.4 g CaCI22H20 0.2 g MgS04 7H20 2.8 g K2HP04 Reference and test solution preparation: A stock solution of the reference substance, 3,5-dichlorophenol, was prepared by dissolving 500 mg in 10 mL of 1N NaOH, diluted to 30 mL with NANOpure water, then brought to the point of incipient precipitation with 1N H2S 04, and diluted to 1 L with NANOpure water. The pH of the reference solution was measured to be 7.18. 000S64 PFOS was added directly to test vessels rather than volumetric addition of a stock solution. This method was deemed appropriate based on the observed solubility of the test substance in water. Test vessels: Mixtures were prepared and aerated in 500 mL Erlenmeyer flasks and then transferred into 300 mL Biochemical Oxygen Demand (BOD) bottles Number of concentrations: 7 plus 3 reference controls and 2 Blank controls Temperature: 19-21C Total Suspended Solids and pH for sludge on day of testing: 4380 mg/L and 7.87 respectively. Element Basis: Respiration inhibition as determined by dissolved oxygen concentration. Method Remarks: Stock solutions of PFOS that were prepared at nominal concentration of approximately 500 and 1000 mg/L in NANOpure water contained test material that was not in solution after 20-minutes of sonication. Therefore, direct weight addition was employed to administer PFOS to the test system. Test mixtures were prepared at 15-minute intervals and aerated until the contact time of the test substance with the activated sludge was three hours. After 3-hours of contact time, dissolved oxygen was measured over a period of up to 10-minutes. RESULTS Nominal concentrations: Two blank controls, three reference substance controls, 0.90, 2.7, 9.0, 27, 90, 271, 905 mg/L test material solutions Statistical Analyses: EC50 values were calculated for the reference material by probit analysis using the computer software of C.E. Stephan. An EC50 value could not be calculated for the test substance. Analytical Methodology: Analysis of DO concentrations in all test solutions were performed at Wildlife International Ltd. using a YSI Model 50B Dissolved Oxygen Meter. Dissolved oxygen readings were recorded every 10 seconds for 10 minutes or until the dissolved oxygen dropped below 1.0 mg/L 0003 Respiration Rates and Percent Inhibitions T reatm en t Control 1 Control 2 3,5-dichlorophenol 3 mg/L 3,5-dichlorophenol 15 mg/L 3,5-dichlorophenol 50 mg/L Test substance 0.90 mg/L Test substance 2.7 mg/L Test substance 9.0 mg/L Test substance 27 mg/L Test substance 90 mg/L Test substance 271 mg/L Test substance 905 mg/L Respiration Rate mg 0 2/L /h o u r 39.6 41.1 31.1 14.6 5.1 38.9 35.1 33.5 37.9 32.7 28.1 24.7 Percent Inhibition NA NA 22.9 63.8 87.4 3.6 13.0 17.0 6.1 19.0 30.4 38.8 Control response: satisfactory CONCLUSIONS The test substance exhibited a maximum inhibitory effect of 38% upon respiration at a nominal test substance concentration of 905 mg/L. The EC50 (respiration inhibition) is therefore greater than the solubility of the test substance. Submitter: 3M Company, Environmental Laboratory, P.O. Box 33331, St. Paul, Minnesota, 55133 DATA QUALITY Reliability: Klimisch ranking 1. REFERENCES This study was conducted at Wildlife International, Ltd. Easton, MD at the request of the 3M Company. OTHER Last changed: 5/3/00 000SG6