Jøran Solnes Skaar1,2, Erik Magnus Ræder3, Lutz Ahrens 4, Roland Kallenborn1,5, Jan Ludvig Lyche3.   1 Faculty of Biotechnology and Food Science (KBM), Norwegian University of Life Sciences (NMBU), NO-1432 Ås, Norway, roland.kallenborn@nmbu.no 2 NILU-Norwegian Institute of Air Research, NO-2007 Kjeller, Norway 3 Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), NO-0033 Oslo, Norway, 4 Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), SE-750 07 Uppsala, Sweden 5 Department of Arctic Technology (AT), University Centre in Svalbard (UNIS), NO-9171 Longyearbyen, Svalbard, Norway. Source elucidation for perfluoroalkyl substances (PFASs) around Svalbard settlements Introduction PFASs (Poly- and perfluoroalkyl substances): Substances where all or the majority of the hydrogens are replaced by fluorine in the molecule. Usage: surfactants, flame retardants and for water- and stain repellants. Occurence: They have been found in Arctic air, water and biota. Distribution: Long-range transport via ocean currents and atmosphere is the major source for Arctic PFASs ⇌ + H+ Main findings Municipal wastewater, leachate from a decomissioned local landfill and fire-fighting training sites identified as point sources for PFASs. No suspected point sources sampled in Barentsburg. The aqueous film forming fire-fighting foams (AF3) contribute mostly with PFSAs (perfluoroalkyl sulfonates). The waste water and landfill leachate contained more PFCAs (perfluoroalkyl carboxylates). The Presence of branched PFOS indicated application of technical PFOS and still active local contamination sources. Linnévatnet can be considered as background site, not influenced by direct input. This site contained more PFCAs, likely illustrating atmospheric input from volatile precursors such as fluorotelomer alcohols (FTOHs) from local sources and long-range transport. Figure 1: Molecular structure of the strong acid PFOS in neutral and ionic (dominant) form, pKa ≈ - 5.5. Table 1: Name and chemical formula of the acronyms used for substances. Linnévatnet Acronym Name Formula PFBA Perfluorobutanoate/acid F(CF2)3COO- PFPeA Perfluoropentanoate F(CF2)4COO- PFHxA Perfluorohexanoic acid F(CF2)5COO- PFHpA Perfluoroheptanoic acid F(CF2)6COO- PFOA Perfluorooctanoic acid F(CF2)7COO- PFNA Perfluorononaoic acid F(CF2)8COO- PFDA Perfluorodecanoic acid F(CF2)9COO- PFUnDA Perfluoroundecanoic acid F(CF2)10COO- PFDoDA Perfluorododecanoic acid F(CF2)11COO- PFBS Perfluorobutane sulfonate F(CF2)4SO32- PFHxS Perfluorohexane sulfonate F(CF2)6SO32- PFOS Perfluorooctane sulfonate (sum of the linear and branched isomers) F(CF2)8SO32- 6:2 FTSA 6:2 Fluorotelomer sulfonate F(CF2)6(CH2)2SO32- FOSA Perfluorooctane sulfonamide F(CF2)8SO2NH2 Σ-PFAS Sum of the above poly- and perfluoroalkyl substances Figure 2: Map of Svalbard. Experimental Locations Grønfjorden (near Barentsburg), Longyearbyen, Lake Linnévatnet and Ny-Ålesund. Sampling Surface water, surface sediment and soil was collected at various locations in April and June 2015 and June 2016. Extraction and analysis Water extraction with solid phase extraction (SPE) Soil/sediments were extracted with Methanol. Analysis: HPLC using a C18 column and detected by negative ESI MS/MS in MRM mode. Quantification: ISTD method, and recoveries were calculated by RSTD added to samples prior to instrumental analysis. Figure 2: PFAS concentrations in water. FFTS = fire-figting training site, WW = waste water, LF = landfill, LW = lake water. Median values, whiskers represent max and min. Figure 5: Pictures during sampling from the ice of Linnévatnet, the fire-fighting training site (FFTS) in Ny-Ålesund and downstream the FFTS at Svalbard Airport in Longyearbyen. Figure 3: PFAS concentrations in soil and sediment. FFTS = fire-figting training site, WW = waste water, LF = landfill, LW = lake water. Median values, whiskers represent max and min. Acknowledgements Thanks to Kings Bay, The Governor of Svalbard, Svalbard Environmental Protection Fund (FluoroImpact project), AMAP and NMR for funding. A special thanks to Stig Magne Lunde, Jelena Racovic, Siri Axelson, Jessica Bosch and Tatiana Drotikova for their contributions in the field, in the laboratory and for logistical support. References Ahrens, L., Rackovic, J., Axelson, S., Kallenborn, R., (2016). Source tracking and impact of per- and polyfluoroalkyl substances at Svalbard Kallenborn, R., Skaar, J. S, Ræder, E. M., Lyche, J. L., (2017). Sources and distribution profiles for per- fluoroalkyl substances in Ny-Ålesund, Svalbard. Skaar, J. S. (2016). Occurrence of Selected Poly- and Perfluoroalkyl Substances (PFAS) in Arctic Freshwater: A Case Study from Svalbard. Ås: Norwegian University of Life Sciences, Ås. Retrieved from http://hdl.handle.net/11250/2398614 Figure 4: PFAS composition patterns in water. FFTS = fire-figting training site, WW = waste water, LF = landfill, LW = lake water.