Document 3wJvzz4rDyBve6N48MVkbDvJ

ARIU'OO? ACUTE EASTERN OYSTER SHELL DEPOSITION TEST SUBSTANCE Identity: Perfluorooctanesulfonate; may also be referred to as PFOS or FC-95. (1-Octanesulfonic add, 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, 19F-NMR and elemental analyses techniques. METHOD Method: OPPTS 850.1025 Type: Static acute GLP: Yes Year completed: Study completed 1999. Report completed 2000 Species: Crassostrea virginica Supplier: P. Cummins Oyster Company, Inc., Baltimore, MD Shell grinding: Prior to test initiation, recently deposited shell at the rounded (ventral) end was removed using a small electric grinder. Care was taken to remove the shell rim uniformly to produce a smooth, rounded, blunt profile. Analytical monitoring: PFOS measured at 0, 48, 96-hours Exposure period: 96-hours Statistical methods: Shell growth inhibition was calculated for each treatment group as the percent reduction in shell growth relative to mean shell growth in the negative control. The EC50 value was estimated by visual inspection of shell growth inhibition data. The shell growth data was evaluated for normality and homogeneity of variances using the ChiSquare test and Bartlett's test, respectively. Dunnett's test was used to identify treatment groups which had a statistically significant (<0.05) reduction in shell growth as compared to the control. Test oyster age: unknown Length: 33.8 (27.8-41.5) mm, Pretreatment: None Test conditions: Dilution water: Natural seawater diluted to a salinity of 20%0with well water Dilution water chemistry (during the 4-week period immediately preceding the test): salinity: 21 (20-21) 7, 000741 pH: TOC: 8.1 (8 .0- 8 .2) < 1.0 mg/L Stock and test solution preparation: Primary stock prepared in dilution water at 9.1 mg/L and mixed for ~24 hours prior to use. After mixing, primary stock solution appeared clear and colorless with some white particulate material suspended throughout the solution. It was proportionally diluted with dilution water to prepare the four additional test concentrations. All test solutions appeared clear and colorless. Due to the relatively low solubility of PFOS in natural seawater, the highest concentration attainable with this matrix is approximately 3.3 mg/L. Concentrations dosing rate: Once Exposure vessels: 52L polyethylene aquaria containing approximately 40L of test solution: water depth approximately 21 cm. Each chamber was continuously stirred to circulate the supplemental algae diet using an electric paddle mixer. Feeding: Algal cells ( Thalassiosira pseudonana, Skeletonema sp., Chaetoceros sp., and Isochrysis sp.) were provided to supplement naturally occurring algae and to maximize oyster growth rates during the test. Number of replicates: one Number of oysters per replicate: twenty Number of concentrations: five plus a negative control Water chemistry during the study: Dissolved oxygen range (0 - 96 hours): 6.6 - 7.6 mg/L (control exposure) 6.1 - 7.7 mg/L (3.0 mg/L exposure) pH range (0 - 96 hours) 7.6 - 8.1 (control exposure) 7.6 - 8.1 (3.0 mg/L exposure) Test temperature range (0 - 96 hours) 22.2 - 22.3C (control exposure) 21.8 - 22.7C (3.0 mg/L exposure) Method of calculating mean measured concentrations: arithmetic mean RESULTS Nominal concentrations: Bk control, 1.2, 2.0, 3.3, 5.5, 9.1 mg/L Measured concentrations: <LOQ, 0.36, 0.40, 1.3, 1.9, 3.0 mg/L Element value: 96-hour EC50 = >3.0 mg/L (C.l. not calculable) 96-hour NOEC = 1.9 mg/L All element values based on mean measured concentrations 000742 Statistical evaluation of shell growth: EC50 values could not be calculated due to insufficient shell growth inhibition at the highest attainable concentration. Analytical Methodology: Analyses of test solutions were performed at Wildlife International Ltd. using high performance liquid chromatography with mass spectrometric detection (HPLC/MS). When determining the concentration of the test substance in the test solutions, the same and most prominent peak response for perfluorooctanesulfonate was used. No attempt was made to quantify on the basis of individual isomeric components. The LOQ (limit of quantitation) was 0.115 mg/L in this study. Samples collected at test initiation had measured values from 28 to 46% of nominal. Measured values for samples taken at 48-hours ranged from 15 to 41 % of nominal. Measured values for samples taken at 96-hours ranged from <LOQ to 52% of nominal. Summary of analytical chemistry data: N om inal T e st C o n c e n tra tio n , m g/L M easured D uplicate V alu es at 0, 4 8 , and 96-hours, Respectively, m g/L M ean M easured C o n c e n tra tio n , m g/L Percent of N om inal N e g a tiv e Control All < L O Q <LOQ . 1 .2 0 .3 3 1 ,0 .3 5 3 , 0.3 4 1 ,0 .4 2 9 , <LO Q , 0 .3 6 <LOQ 30 2 .0 0.622, 0.633, 0.2 99, 0.313, 0.249, 0 .4 0 0 .2 5 7 20 3 .3 1.36, 1.15, 0 .9 24, 0 .8 78, 1.58, 1.72 1.3 39 5 .5 2 .4 2, 2.5 3, 2 .0 2 , 2 .2 4, 1.45, 0.970 1 .9 35 9.1 3 .3 9 , 3 .4 4 , 3 .0 1 *, 3 .7 4 , 3 .5 7 , 1.9 9 , 2 .1 9 *3 replicates analyzed at time 0 3 .0 33 Biological observations after 96-hours: Oysters in the negative control and all PFOS treatment groups appeared normal and healthy throughout the exposure period. 000743 Shell deposition and shell growth inhibition at test termination: M ean M easured C o n c e n tra tio n , m g/L Shell Deposition Mean + SD , mm P ercen t Inhibition in S h e ll G ro w th N eg ative Control 2.6 7 + 0.824 . 0 .3 6 2.50+ 0.933 6 .4 0 .4 0 2.4 0 + 0.820 10 1.3 2.51 + 0 .9 19 6.0 1.9 2 .1 3 + 0.804 20 3.0 1.91 + 0.591 28 Mortality of controls: None CONCLUSIONS The potassium perfluorooctanesulfonate 96-hour EC50 for the Eastern Oyster was determined to be > 3.0 mg/L, the highest concentration tested and the practical limit of solubility in unfiltered seawater. The 96-hour no effect concentration was 1.9 mg/L. 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 000744