Increasing concentrations of perfluoroalkyl acids in Scandinavian otters (Lutra lutra) between 1972 and 2011 a new threat to the otter population?

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1 Supporting Information Increasing concentrations of perfluoroalkyl acids in Scandinavian otters (Lutra lutra) between 1972 and 211 a new threat to the otter population? Anna Roos 1,2,*, Urs Berger 3, Ulf Järnberg 3, Jiska van Dijk 4 and Anders Bignert 1 1 Swedish Museum of Natural History, PO Box 57, SE-14 5 Stockholm, Sweden 2 Uppsala University, Norbyvägen 18A, SE Uppsala, Sweden 3 Stockholm University, SE Stockholm, Sweden 4 Norwegian Institute for Nature Research (NINA), NO-7485 Trondheim, Norway * Corresponding author phone , fax anna.roos@nrm.se Contents Chemical analysis Table S1. Perfluoroalkyl substances included in this study. Pages S2 Page S3 Table S2. Median concentrations (ranges) of PFAAs in otter livers (ng/g ww) collected from three areas Page S4 Table S3. The statistical power for the whole trend as well as for the last ten years. Also, the least detectable change in % with a power of 8% for the whole series as well as for the last ten years is shown. Page S5 Figure S1. Map of the three sampling areas: South-western Norway (red), southern Sweden (green) and northern Sweden (blue). The individual otters included in the geographical trend are indicated. Page S6 Figure S2. Relative PFCA patterns (top) and PFSA patterns (bottom) in otters collected in from three areas, northern Sweden (N Swe), southern Sweden (S Swe) and south western Norway (NORW). Page S7 Figure S3. PFHxS and FOSA did not show a significant time trend over the study period (ng/g ww in liver). Page S8 S1

2 Chemical analysis In the first method used up to 25 the sample (1 g liver) was homogenised in five volumes (1:5) of ultra-pure water (MilliQ, EMD Millipore Corporation, Billerica, MA, USA). A volume of 1 ml of the homogenate was transferred to a polypropylene (PP) tube, together with 2 ml of 1 M sodium carbonate buffer, and 1 ml of 1 mm tetrabutylammonium (TBA) solution at ph 1. The mixture was then shaken thoroughly (Vortex ) for 2 seconds. A volume of 5 ml methyl tertiary butyl ether (MTBE) was added and the tube was gently turned for 2 minutes. After centrifugation, the MTBE phase was quantitatively transferred to a new PP tube, another 5 ml of MTBE was added to the first tube and the extraction procedure was repeated. The two MTBE extracts were combined, and the MTBE was gently evaporated to dryness with dry nitrogen gas. The residuals were then dissolved in exactly 5 µl of methanol. All extracts were finally filtered through a.46 µm PP filter prior to analysis. Instrumental analysis in the first method was based on high performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (MS/MS) in the negative ion electrospray ionization mode, employing an Alliance 2695 HPLC system (Waters, Milford, MA) and a Quattro II MS/MS instrument (Micromass, Altrincham, UK). All instrumental parameters and settings are described in detail in Holmström et al. (ref 25 in the main document). Quantification was done using the response factors calculated from the analyte signals in spiked and extracted samples (external matrix-matched calibration). Concentration levels of the spikes were chosen to match the concentration interval of the samples in the batch. The method detection limits (MDLs) were calculated from a low level spiked and extracted sample. In the second method used from 28 the liver samples (1 g) were spiked with 5 µl of a mixture of isotopically mass-labeled internal standards (ISTDs) in methanol containing.2 ng/µl of each ISTD ( 13 C 2 -PFHxA, 13 C 4 -PFOA, 13 C 5 -PFNA, 13 C 2 -PFDA, 13 C 2 -PFUnDA, 13 C 2 - PFDoDA, 18 O 2 -PFHxS and 13 C 4 -PFOS, all from Wellington, Guelph, Canada). The samples were extracted twice with 5 ml of acetonitrile in an ultrasonic bath (15 min, room temperature). The combined extracts were concentrated to 1 ml and underwent dispersive clean-up on 25 mg graphitized carbon (Supelclean ENVI-Carb 12/4, Supelco, Sigma- Aldrich, Stockholm, Sweden) and 5 µl glacial acetic acid. Aliquots of.5 ml of the cleaned-up extracts were diluted with.5 ml of 4 mm aqueous ammonium acetate and kept at 4 C until the day of analysis. The extracts were allowed to warm to room temperature, vortex mixed and centrifuged before the clear solution was transferred to an autoinjector vial. Instrumental analysis and quantification in the second method was done as described in detail by Holmström and Berger (ref 35 in the main document). The same instrumentation as in the first method was employed. Quantification was performed in selected reaction monitoring chromatograms using the internal standard method. For analytes that did not have authentic mass-labeled standards, the following ISTDs were used for quantification. 13 C 4 -PFOA for PFHpA, 13 C 2 -PFDoDA for PFTrDA, PFTeDA and PFPeDA, 18 O 2 -PFHxS for PFBS and 13 C 4 - PFOS for PFDS and FOSA. Due to the lack of an analytical reference standard for PFPeDA, this analyte was quantified using the relative response factor of PFTeDA. MDLs were determined on the basis of procedural blank extractions, which were performed with every batch of samples. S2

3 Table S1. Perfluoroalkyl substances included in this study. Acronym Total number of carbons CAS-no 1 Perfluoroalkyl carboxylic acids (PFCAs) Perfluorohexanoic acid PFHxA Perfluoroheptanoic acid PFHpA Perfluorooctanoic acid PFOA Perfluorononanoic acid PFNA Perfluorodecanoic acid PFDA Perfluoroundecanoic acid PFUnDA Perfluorododecanoic acid PFDoDA Perfluorotridecanoic acid PFTrDA Perfluorotetradecanoic acid PFTeDA Perfluoropentadecanoic acid PFPeDA Perfluoroalkane sulfonic acids (PFSAs) and FOSA Perfluorobutane sulfonic acid PFBS Perfluorohexane sulfonic acid PFHxS Perfluorooctane sulfonic acid PFOS Perfluorodecane sulfonic acid PFDS Perfluorooctane sulfonamide FOSA CAS-no for the acid form S3

4 Table S2. Median concentrations (ranges) of PFAAs in otter livers (ng/g ww) collected from three areas PFOA PFNA PFDA PFUnDA PFDoDA PFTrDA PFTeDA PFPeDA PFHxS PFOS PFDS FOSA Northern Sweden (n=16) 5.3 (1.3-71) 68 (22-637) 46 (14-174) 47 (15-137) 8.2 (3.4-2) 13 (4.4-39).9 (.4-3.5).8 (.3-1.5) 2.8 (.7-12) 266 (73-554).6 (.3-6.1) 12 (.9-88) Southern Sweden (n=46) 9. (1.1-44) 86 (14-234) 71 (6.-31) 53 ( ) 8.8 (1.2-63) 9.4 (1.6-27) 1.2 (.1-11).5 (.2-2.2) 5.5 (.7-64) 83 (32-735) 2.2 (.2-57) 8.6 (1.-93) South-west Norway (n=17) 13 (8.-23) 53 (25-89) 32 (16-54) 35 (16-79) 7.2 (3.9-15) 11 (5.4-22) 2.5 (1.-4.1).4 (.1-.9) 3.6 ( ) 21 (63-37).9 (.3-5.2) 25 (1.2-43) S4

5 Table S3. The statistical power for the whole trend as well as for the last ten years. Also, the least detectable change in % with a power of 8% for the whole series as well as for the last ten years is shown. Power for the whole period (%) Power for the last ten years (%) Least detectable change (%) with a power of 8% for the whole period Least detectable change (%)with a power of 8% for the last ten years PFOA PFNA PFDA PFUnDA PFDoDA PFTrDA PFTeDA PFHxS PFOS PFDS FOSA S5

6 km 55 TISS :37, map_8 Figure S1. Map of the three sampling areas: South-western Norway (red), southern Sweden (green) and northern Sweden (blue). The individual otters included in the geographical trend are indicated. S6

7 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% % N Swe S Swe NORW PFPeDA PFTeDA PFTrDA PFDoDA PFUnDA PFDA PFNA PFOA 1% 9% 8% 7% 6% 5% 4% 3% 2% 1% % N Swe S Swe NORW FOSA PFDS PFOS PFHxS Figure S2. Relative PFCA patterns (top) and PFSA patterns (bottom) in otters collected in from three areas, northern Sweden (N Swe), southern Sweden (S Swe) and south western Norway (NORW). S7

8 PFAS (ng/g) in Otter liver PFAS (ng/g) in Otter liver PFTeDA PFPeDA PFHxS PFOS PFDS FOSA Source: Anna Roos, NRM :41, reg3_1_u Source: Anna Roos, NRM :55, reg4_1_u Figure S3. PFHxS and FOSA did not show a significant time trend over the study period (ng/g ww in liver). S8