Document 7MmY0Nvda53zXqZgQM2QaywgB

BACK TO MAIN ACCUMULATION OF PERFLUOROOCTANESULFONATE AND RELATED FLUOROCHEMICALS IN MINK AND RIVER OTTERS John P. Giesy* Kurunthachalam Kannan Department of Zoology, National Food Safety and Toxicology Center, Institute for Environmental Toxicology, Michigan State University, East Lansing, MI 48824, USA *To whom correspondence should be addressed: Prof. J.P. Giesy 218C National Food Safety and Toxicology Center Michigan State University East Lansing, MI 48824 USA Tel: (517)-353-2000; Fax: 517-432-2310; E- mail: jgiesy@aol.com Prepared for: 3M St. Paul, MN June 20, 2001 1 BACK TO MAIN SUMMARY This report is a compilation of results of a survey of perfluorooctanesulfonate (PFOS), perfluorooctanesulfonamide (FOSA), perfluorooctanoic acid (PFOA) and perfluorohexanesulfonate (PFHS) in mink and river otters from the US. PFOS was found in all the samples of mink and river otter livers analyzed in this study. The greatest concentration of PFOS found in mink liver was 4800 ng/g, wet wt. PFOSA, PFOA and PFHS were detected only in <10% of the mink samples analyzed. River otters collected from Orgeon and Washington states contained PFOS in livers at concentrations ranging from 34 to 994 ng/g, wet wt. INTRODUCTION Mink (Mustela vison) are carnivores in aquatic ecosystems and used as sentinel species for assessing the effects of environmental contaminants in aquatic environments. Mink are mostly piscivores, have a fairly small home range, live close to watershed, and prefer to catch prey in rivers, streams and ponds. Mink have been identified as an indicator species of water quality and ecosystem integrity for the Great Lakes basin (1). In screening of wildlife for the accumulation of perfluorooctanesulfonate (PFOS) across a range of species and habitats, mink fed with carp from Saginaw Bay, Michigan, contained some of the greatest concentrations observed (2). This report is a compilation of the concentrations of PFOS, FOSA, PFOA and PFHS in the livers of mink collected from Illinois, Massachusetts, South Carolina and Louisiana. In addition, a closely related mustelid species, river otter, collected from Oregon and Washington were also analyzed for the presence of target fluorochemicals. MATERIALS AND METHODS Livers of mink were obtained from various watersheds in Illinois, Massachusetts, South Carolina and Louisiana. Similarly, livers of river otters were obtained from trappers in Washington and Oregon states. All the samples were collected during 1995-2000. Samples were wrapped in clean aluminum foil and stored at -20C until analyzed. Analysis Details of the analytical procedures have been outlined in standard operating procedures for the analysis of fluorochemicals in tissue which are referenced below. Preparatory Methods. ETS-8-6.0, "Extraction of Potassium Perfluorooctanesulfonate or other Fluorochemical Compounds from Liver for Analysis using HPLCElectrospray/Mass Spectrometry". 3M Environmental Laboratory, St. Paul, MN.The analytical work was generated by 3M Environmental Laboratory. (Refer to Reference (3) for the specific reports.) An ion-pairing reagent was added to the sample and the analyte ion pair was partitioned into methyl-tert-butyl ether (MtBE). The extract was transferred to a centrifuge tube and put onto a nitrogen evaporator until dry. Each extract was reconstituted in 1.0 mL of 2 BACK TO MAIN methanol, and then filtered through a 3 cc plastic syringe attached to a 0.2 m nylon filter into glass autovials. Analytical Methods. ETS-8-7.0, "Analysis of Potassium Perfluorooctanesulfonate or other Fluorochemicals in Liver Extracts Using HPLC-Electrospray/Mass Spectrometry". 3M Environmental Laboratory, St. Paul, MN. The analyses were performed using HPLC-ES/MS/MS by monitoring a single product ion selected from a primary ion characteristic of a particular fluorochemical. For example, molecular ion 499, selected as the primary ion for PFOS (C8F17SO3-) analysis, was fragmented further to produce ion 99 (FSO3-). The characteristic product ion 99 was monitored for quantitative analysis. Analytical Equipment The following are representative of the actual settings used during the analytical phase of this study. Liquid Chromatograph: Hewlett-Packard Series 1100 Analytical column: Keystone BetasilTM C18 2x50 mm Ambient; Mobile phase components: Component A: 2mM ammonium acetate Component B: methanol Flow rate: 300 L/min Injection volume: 10 L Solvent Gradient: 16.0 minutes Time (minutes) %B 0.0 10% 1.0 10% 6.0 90% 11.0 100% 13.0 10% Liquid Chromatograph system (5 m) Column temperature: Mass Spectrometer: Micromass API/Mass Spectrometer Quattro IITM Triple Quadrupole system Software: Mass LynxTM 3.4 Cone Voltage: 30-60 V Collision Gas Energy: 25-45 eV Mode: Electrospray Negative Source Block Temperature: 150C 10C Electrode: Z-spray Analysis Type: Multiple Reaction Monitoring (MRM) 3 BACK TO MAIN Target Ions Monitored in 3M Laboratory Analyses Target Analyte Primary Ion (AMU) Product Ion (AMU) PFOS 499 80, 99 FOSA 498 78 PFOA 413 169 PFHS 399 99 THPFOS1 427 80 1 THPOS, Tetra-hydro perfluorooctanesulfonate, is used as a surrogate to monitor for gross instrument failure. Data Quality Objectives and Data Integrity The following data quality objectives were indicated in the method performance section of ETS-8-7.0, Analysis of Potassium Perfluorooctanesulfonate or Other Fluorochemicals in Liver Extracts Using HPLC-Electrospray/Mass Spectrometry: Linearity: The coefficient of determination (r) equal to or greater than 0.980. Limits of Quantitation (LOQ): The LOQ is equal to the lowest acceptable standard in the calibration curve. Acceptable Spike Recoveries: Matrix spikes prepared in rabbit liver must be recovered at 70-130% for the analytical run to be valid. Blanks: Matrix or surrogate matrix blanks must have a peak area < the peak area of the lowest acceptable standard (LOQ). Summary of Quality Control Analyses Results Linearity: The coefficient of determination (r) of the standard curve was >0.980. Calibration Standards: Quantitation of the target analytes was based on a quadratic curve weighted 1/x of a single, opening or two bracketing unextracted curves for each group of samples. High or low points on the curve may have been deactivated to provide a better fit over the curve range most appropriate to the data. Low curve points with peak areas less than two times that of the extraction blanks were deactivated to disqualify a data range that may have been significantly affected by background levels of the analyte. Occasionally, a single mid-range curve point that was an obvious outlier may have been deactivated. Quantitation of each analyte was based on the response of one or more specific product ion(s) using the multiple reaction- monitoring mode of the instrument. Calibration standards were prepared to run, undiluted, approximately within the linear range of the instrument (approximately 0.5-1000 ng/g). Limits of Quantitation (LOQ): The LOQ is equal to the lowest acceptable standard in the calibration curve (defined as a standard within 30% of the theoretical value), and is at least two times the analyte peak area detected in the surrogate matrix blanks. Because low levels of the target analytes are ubiquitous in the laboratory, it is imperative that these criteria for LOQ determination be observed. The approximate LOQ for each analyte in each matrix is listed on the results summary table. 4 BACK TO MAIN Blanks: All blanks were below the limit of quantitation for the compounds of interest, except for one water blank for PFHS. These outliers will not adversely affect the outcome of this study. Given the nature of the samples encompassed by this study, the wellcharacterized matrix of rabbit liver was used as surrogate tissue for matrix blanks. These surrogate matrix blanks were < the level of the LOQ. Precision, Instrumental: Instrumental precision was not specifically determined within the course of this study. In other, similar liver/tissue studies, instrumental precision has been determined to be better than 7% for all target analytes. Matrix Spikes: At least one set of matrix spikes was prepared for each type of tissue from each type of animal; spikes were prepared at approximately 600 ng/g. Recoveries of PFOS varied and were greater than 100% in most cases. Therefore, adequate caution should be exercised in interpreting the results. Matrix spike recoveries are summarized in Appendix IV. To verify the status of the extraction and analytical systems, matrix spikes were also prepared in a well-characterized surrogate matrix, rabbit liver. The matrix spike studies conducted in rabbit were all acceptable (+/-30%) for those analytical runs used when reporting data for samples and matrix spikes. Demonstration of Specificity: Specificity for analyte identification was demonstrated by chromatographic retention time and mass spectral daughter ion characterization. Additional confirmatory tests were performed for PFOS. In the electrospray tandem mass spectrometry (ESMSMS) system, the 499 Da 80 Da transition can provide a stronger signal than the 499 Da 99 Da transition of the PFOS analysis. However, in the analysis of tissue samples collected from some species of animals, an unidentified interferent was present in the 499 Da 80 Da transition. Although this interferent is rarely observed, to ensure complete selectivity, quantitation was based on the 499 Da 99 Da transition. To verify the identity of the detected analyte, in samples determined to contain PFOS at > 70 ng/g, at least 2 transitions were monitored and showed quantitative agreement to within +/-30%. Typically, 499>99 and 499>80 transitions were monitored. On the occasions that these two transitions differed by more than 30%, the sample was reanalyzed monitoring the 499>130 transition. This third transition showed quantitative agreement with the reported data from the 499>99 determination. Statement of Data Quality It is not possible to verify true recovery of endogenous analyte from tissues without radiolabelled reference material. The only measurement of accuracy available at this time, matrix spike studies, indicate that the data can be reported with a stated accuracy of +/-50%. Details of matrix spike recoveries are summarized in Appendix IV. The concentrations of PFOS, FOSA, PFOA and PFHS were not corrected for the recoveries of the surrogate standard or matrix spike recoveries. The concentrations reported in the 5 BACK TO MAIN appendices were corrected for purity of the PFOS standard. Also, no attempt was made to correct the fluorochemical concentrations for moisture content in relevant tissues such as liver. RESULTS AND DISCUSSION The recoveries of PFOS spiked to mink liver matrices were greater than 100% in all the cases. The reason for this is not known. The accuracy of PFOS concentrations reported in this document should be 50%. PFOS was found in livers of all the mink samples analyzed (Appendices I to III). The highest concentration of 4800 ng/g, wet wt, was found in a mink collected from Illinois. The highest concentrations of PFOS in mink from Louisiana and South Carolina were 2000 and 3110 ng/g, wet wt, respectively. Livers of mink collected from Massachusetts contained PFOS concentration of up to 4300 ng/g, dry wt. PFOA was found in a few mink livers from Massachusetts at concentrations ranging from <18 to 108 ng/g, dry wt. PFOA was not found in any of the mink from Louisiana, South Carolina and Illinois. FOSA and PFHS were found in a few individuals from Illinois at concentrations ranging from <38 to 590 ng/g, wet wt and <6.8 to 85 ng/g, wet wt, respectively. FOSA was not found at quantifiable concentrations in minks from South Carolina and Louisiana. Livers of river otters from Washington and Oregon States also contained quantifiable concentrations of PFOS. Concentrations of PFOS in river otters were in the range of 34 to 994 ng/g, wet wt. FOSA was detected in four of the 5 samples analyzed at concentrations ranging from <38 to 72 ng/g, wet wt. Concentrations of PFOA in river otter livers were less than the quantification limit of 36 ng/g, wet wt. REFERENCES (1) U.S. Environmental Protection Agency (1993) Wildlife Criteria Portions of the Proposed Water Quality Guidance for the Great Lakes System. Washington, DC. Office of Science and Technology and Office of Water. (2) Giesy, J.P.; Kannan, K. Global distribution of perfluorocotane sulfonate in wildlife. Environ. Sci. Technol. 2001, 35, 1339-1342. (3) 3M Environmental Laboratory, St. Paul, MN LIMs Report numbers; W2491, W3197, E00-1386, E00-1922, E00-2456. 6 BACK TO MAIN 7 BACK TO MAIN APPENDIX I Concentrations of (ug/g, wet) fluorochemicals in biota Species River Otter River Otter River Otter River Otter River Otter Lab ID W2491-29,RAG 066 W2491-30,RAG 028 W2491-31,RAG 148 W2491-32,RAG 230 W2491-33,RAG 237 Tissue Liver Liver Liver Liver Liver Location Washington/Oregon Rivers Washington/Oregon Rivers Washington/Oregon Rivers Washington/Oregon Rivers Washington/Oregon Rivers PFOS 0.279 0.994 0.189 0.034 0.151 FOSA 0.037 0.045 0.072 <LOQ ( 0.0375) 0.039 PFOA <LOQ ( 0.0359) <LOQ ( 0.0359) <LOQ ( 0.0359) <LOQ ( 0.0359) <LOQ ( 0.0359) PFOS = Perfluorooctanesulfonate PFHS = Perfluorohexanesulfonate FOSA = Perfluorooctanesulfonamide PFOA = Perfluorooctanoate APPENDIX II Concentrations of (ug/g, wet) fluorochemicals in mink from Illinois Species Lab ID Tissue Location PFOS LOQ = Limit of quantitation- values in parenthesis PFOA FOSA PFHS Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink C23 (45) C26 (44) C27 (49) C33 (46) C35 (47) C37 (48) C42 (43) C44 (54) D10 (50) F15 (55) F19 (56) Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US 0.801 0.443 0.145 0.435 0.355 0.833 0.420 0.237 1.67 0.548 0.783 < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) 0.038 < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) 0.083 < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) 0.008 < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) 8 BACK TO MAIN Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink F21 (57) F24 (58) P01 (60) P03 (64) P09 (61) S11 (37) S15 (41) S18 (40) S19 (59) S25 (39) S30 (36) S35 (42) S39 (38) T01 (51) T04 (53) T03 (52) V12 (62) V03 (65) V08 (63) Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver PFOS = Perfluorooctanesulfonate PFHS = Perfluorohexanesulfonate PFOA = Perfluorooctanoate Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US Midwestern US 1.03 0.868 2.16 4.80 0.841 0.902 1.27 1.99 2.68 0.509 0.186 0.093 0.317 0.633 1.35 0.565 4.87 1.52 3.65 < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) < LOQ (0.0359 ug/g) 0.058 < LOQ (0.0376 ug/g) 0.551 0.590 < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) 0.041 0.132 < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) < LOQ (0.0376 ug/g) 0.345 0.059 0.059 < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) 0.031 0.085 < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) 0.010 < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) 0.010 < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) < LOQ (0.00683 ug/g) FOSA = Perfluorooctanesulfonamide LOQ = Limit of quantitation - values in parenthesis 9 BACK TO MAIN APPENDIX III Concentrations of (ug/g, wet wt, for Louisiana and Alabama samples, ug/g, dry wt, for Massachusetts samples) fluorochemicals in mink from Louisiana, Alabama and Massachusetts. Only freeze-dried liver tissues were available for Massachusetts samples, and therefore the values are on a dry weight basis. Species Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Lab ID (83) SC-01 (84) LA -02+ (85) LA -09 (86) LA -06 (87) LA -04 (88) LA -03 (89) LA -07+ (90) LA -14 (91) SC-09 (92) SC-02 (93) SC-08 (94) SC-11 (95) SC-04 (96) SC-10 Tissue Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Location South Carolina, USA Louisiana Louisiana Louisiana Louisiana Louisiana Louisiana Louisiana South Carolina, USA South Carolina, USA Liver Liver Liver Liver South Carolina, USA South Carolina, USA South Carolina, USA South Carolina, USA PFOS 2.04 0.318 0.218 0.0628 0.127 0.0404 0.0893 0.115 1.50 1.99 3.11 0.646 1.24 2.84 FOSA < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) PFOA < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) PFHS 0.0221 < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) 0.0386 0.0113 < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 < LOQ (0.00750 ug/g) 0.0297 0.0156 0.0364 10 Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink BACK TO MAIN (97) SC-03 (98) SC-06 (99) 990061 (100) 9900153 (101) 990150 (102) 96181 (103) 960232 (104) 9600235 (105) 96029 (106) 96012 (107) 960337 (108) 96185 (109) 96002 (110) 960144 (111) 96336 (112) 96052 (113) 96057 (114) 96184 (115) 960068 Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver South Carolina, USA South Carolina, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA 2.39 3.01 2.48 2.40 0.635 0.562 1.26 0.296 0.489 0.209 0.478 4.30 0.269 1.05 1.85 0.984 0.435 2.45 0.541 < LOQ (0.0750 ug/g) < LOQ (0.0750 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) < LOQ (0.0187 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) 0.404 <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) 0.212 <LOQ (0.0750 ug/g) ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0184 0.0398 0.0204 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0200 0.0281 0.0315 0.0208 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0366 0.0353 0.0248 0.0231 0.00765 < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.00750 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0503 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0479 < LOQ (0.0188 ug/g) 11 BACK TO MAIN Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink Mink (116) 960158 (117) 960136 (118) 96027 (119) 960141 (120) 96020 (121) 960236 (122) 96186 (123) 96009 (124) 96001 (125) 960148 (126) 960008 (127) 960053 (128) 960138 (129) 96027 PFOS = Perfluorooctanesulfonate PFHS = Perfluorohexanesulfonate PFOA = Perfluorooctanoate Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Liver Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA Massachusetts, USA 3.79 0.649 0.252 1.29 1.11 1.04 1.62 0.295 0.597 0.370 0.516 4.16 0.0870 0.515 FOSA = Perfluorooctanesulfonamide 0.180 <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) 0.679 <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) <LOQ (0.0750 ug/g) 0.0320 0.0222 0.0227 0.0264 0.108 < LOQ (0.0188 ug/g) 0.0393 < LOQ (0.0188 ug/g) 0.0203 < LOQ (0.0188 ug/g) 0.0279 0.0258 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0692 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) 0.0290 < LOQ (0.0188 ug/g) < LOQ (0.0188 ug/g) LOQ = Limit of quantitation - values in parenthesis 12 BACK TO MAIN APPENDIX IV Matrix spike recoveries (%) of fluorochemicals spiked to mink livers Matrix Mink liver S19 Mink liver P09 River otter liver RAG195 Mink liver Mink liver 2 PFOS (Mean +/- RSD or PRD) 280+/ -3 3 187+/ -4 8 75+/-2 131+/ -5 7 166+/ -1 0 0 FOSA (Mean +/RSD or RPD) 71+/-195 70+/-7 65+/-0 54 40 PFOA (Mean +/- RSD or RPD) 140+/ -2 0 107+/ -9 71+/-3 107 53 RPD= Relative percent difference; RSD= Relative standard deviation PFOS = Perfluorooctanesulfonate FOSA = Perfluorooctanesulfonamide PFHS = Perfluorohexanesulfonate PFOA = Perfluorooctanoate PFHS (Mean +/- RSD or RPD) 48+/-203 50+/-6 79+/-7 63 67 13