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  • 1.
    Benskin, Jonathan P.
    et al.
    Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB, Canada..
    Ahrens, Lutz
    Helmholtz Zentrum Geesthacht, Inst Coastal Res, Geesthacht, Germany..
    Muir, Derek C. G.
    Environm Canada, Aquat Ecosyst Protect Res Div, Water Sci & Technol Directorate, Burlington, ON L7R 4A6, Canada..
    Scott, Brian F.
    Environm Canada, Aquat Ecosyst Protect Res Div, Water Sci & Technol Directorate, Burlington, ON L7R 4A6, Canada..
    Spencer, Christine
    Environm Canada, Aquat Ecosyst Protect Res Div, Water Sci & Technol Directorate, Burlington, ON L7R 4A6, Canada..
    Rosenberg, Bruno
    Fisheries & Oceans Canada, Arctic Aquat Res Div, Winnipeg, MB, Canada..
    Tomy, Gregg
    Fisheries & Oceans Canada, Arctic Aquat Res Div, Winnipeg, MB, Canada..
    Kylin, Henrik
    Linkoping Univ, Dept Water & Environm Studies, S-58183 Linkoping, Sweden..
    Lohmann, Rainer
    Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA..
    Martin, Jonathan W.
    Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB, Canada..
    Manufacturing Origin of Perfluorooctanoate (PFOA) in Atlantic and Canadian Arctic Seawater2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 2, p. 677-685Article in journal (Refereed)
    Abstract [en]

    The extent to which different manufacturing sources and long-range transport pathways contribute to perfluorooctanoate (PFOA) in the world's oceans, particularly in remote locations, is widely debated. Here, the relative contribution of historic (i.e., electrochemically fluorinated) and contemporary (i.e., telomer) manufacturing sources was assessed for PFOA, in various seawater samples by an established isomer profiling technique. The ratios of individual branched PFOA isomers were indistinguishable from those in authentic historic standards in 93% of the samples examined, indicating that marine processes had little influence on isomer profiles, and that isomer profiling is a valid source apportionment tool for seawater. Eastern Atlantic PFOA was largely (83-98%) of historic origin, but this decreased to only 33% close to the Eastern U.S. seaboard. Similarly, PFOA in the Norwegian Sea was near exclusively historic, but the relative contribution decreased to similar to 50% near the Baltic Sea. Such observations of contemporary PFOA in coastal source regions coincided with elevated concentrations, suggesting that the continued production and use of PFOA is currently adding to the marine burden of this contaminant. In the Arctic, a spatial trend was observed whereby PFOA in seawater originating from the Atlantic was predominantly historic (up to 99%), whereas water in the Archipelago (i.e., from the Pacific) was predominantly of contemporary origin (as little as 17% historic). These data help to explain reported temporal and spatial trends from Arctic wildlife biomonitoring, and suggest that the dominant PFOA source(s) to the Pacific and Canadian Arctic Archipelago are either (a) from direct emissions of contemporary PFOA via manufacturing or use in Asia, or (b) from atmospheric transport and oxidation of contemporary PFOA-precursors.,

  • 2.
    Benskin, Jonathan P.
    et al.
    Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB T6G 2G3, Canada..
    Muir, Derek C. G.
    Environm Canada, Aquat Contaminants Res Div, Burlington, ON L7R 4A6, Canada..
    Scott, Brian F.
    Environm Canada, Aquat Contaminants Res Div, Burlington, ON L7R 4A6, Canada..
    Spencer, Christine
    Environm Canada, Aquat Contaminants Res Div, Burlington, ON L7R 4A6, Canada..
    De Silva, Amila O.
    Environm Canada, Aquat Contaminants Res Div, Burlington, ON L7R 4A6, Canada..
    Kylin, Henrik
    Linkoping Univ, Dept Water & Environm Studies, SE-58183 Linkoping, Sweden..
    Martin, Jonathan W.
    Univ Alberta, Dept Lab Med & Pathol, Edmonton, AB T6G 2G3, Canada..
    Morris, Adam
    Univ Guelph, Dept Environm Biol, Guelph, ON N1G 2W1, Canada..
    Lohmann, Rainer
    Univ Rhode Isl, Grad Sch Oceanog, Narragansett, RI 02882 USA..
    Tomy, Gregg
    Dept Fisheries & Oceans Canada, Arctic Aquat Res Div, Winnipeg, MB R3T 2N6, Canada..
    Rosenberg, Bruno
    Dept Fisheries & Oceans Canada, Arctic Aquat Res Div, Winnipeg, MB R3T 2N6, Canada..
    Taniyasu, Sachi
    Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058569, Japan..
    Yamashita, Nobuyoshi
    Natl Inst Adv Ind Sci & Technol, Tsukuba, Ibaraki 3058569, Japan..
    Perfluoroalkyl Acids in the Atlantic and Canadian Arctic Oceans2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 11, p. 5815-5823Article in journal (Refereed)
    Abstract [en]

    We report here on the spatial distribution of C-4, C-6, and C-8 perfluoroalkyl sulfonates, C-6-C-14 perfluoroalkyl carboxylates, and perfluorooctanesulfonamide in the Atlantic and Arctic Oceans, including previously unstudied coastal waters of North and South America, and the Canadian Arctic Archipelago. Perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) were typically the dominant perfluoroalkyl acids (PFAAs) in Atlantic water. In the midnorthwest Atlantic/Gulf Stream, sum PFAA concentrations (Sigma PFAAs) were low (77-190 pg/L) but increased rapidly upon crossing into U.S. coastal water (up to 5800 pg/L near Rhode Island). Sigma PFAAs in the northeast Atlantic were highest north of the Canary Islands (280-980 pg/L) and decreased with latitude. In the South Atlantic, concentrations increased near Rio de la Plata (Argentina/Uruguay; 350-540 pg/L Sigma PFAAs), possibly attributable to insecticides containing N-ethyl perfluorooctanesulfonamide, or proximity to Montevideo and Buenos Aires. In all other southern hemisphere locations, Sigma PFAAs were <210 pg/L. PFOA/PFOS ratios were typically >= 1 in the northern hemisphere, similar to 1 near the equator, and <= 1 in the southern hemisphere. In the Canadian Arctic, Sigma PFAAs ranged from 40 to 250 pg/L, with perfluoroheptanoate, PFOA, and PFOS among the PFAAs detected at the highest concentrations. PFOA/PFOS ratios (typically >>1) decreased from Baffin Bay to the Amundsen Gulf; possibly attributable to increased atmospheric inputs. These data help validate global emissions models and contribute to understanding of long-range transport pathways and sources of PFAAs to remote regions.

  • 3. Bidleman, T. F.
    et al.
    Kylin, H.
    Jantunen, L. M.
    Helm, P. A.
    MacDonald, R. W.
    Hexachlorocyclohexanes in the Canadian Archipelago. 1. Spatial distribution and pathways of alpha-, beta- and gamma-HCHs in surface water2007In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 41, no 8, p. 2688-2695Article in journal (Refereed)
    Abstract [en]

    Hexachlorocyclohexanes (HCHs) in the surface water of the Canadian Archipelago and south Beaufort Sea were measured in summer, 1999. Overall concentrations of HCH isomers were in order of abundance: alpha-HCH (3.5 +/- 1.2 ng L(-1)) > gamma-HCH (0.31 +/- 0.07 ng L(-1)) > beta-HCH (0.10 +/- 0.03 ng L(-1)). Concentrations and ratios of alpha-HCH/gamma-HCH decreased significantly (p < 0.001 to 0.003) from west to east, but there was no significant variation in alpha-HCH/ beta-HCH. The (+) enantiomer of alpha-HCH was preferentially degraded, with enantiomer fractions (EFs) ranging from 0.432-0.463 and increasing significantly (p < 0.001) from westtoeast. Concentrations alsovaried latitudinally for alpha-HCH and gamma-HCH (p < 0.002) but not for beta-HCH. Principal component analysis with variables alpha-HCH and gamma-HCH concentrations, EF, latitude, and longitude accounted for 71% (PC 1) and 16% (PC 2) of the variance. Mixing in the eastern Archipelago was modeled by assuming three end members with characteristic concentrations of alpha-HCH and gamma-HCH, The model accounted for the observed concentrations and higher EFs of alpha-HCH at the eastern stations.

  • 4. Carrizo, Daniel
    et al.
    Gustafsson, Orjan
    Distribution and Inventories of Polychlorinated Biphenyls in the Polar Mixed Layer of Seven Pan-Arctic Shelf Seas and the Interior Basins2011In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 45, no 4, p. 1420-1427Article in journal (Refereed)
    Abstract [en]

    Assessment of the Arctic as a global repository of polychlorinated biphenyls (PCBs) and of uptake processes in the base of its marine food chain hinges on reliable information of PCB distribution in surface seawater, yet there is a scarcity of quality-assured PCB measurements in this key compartment. Here, surface seawater PCB concentrations and congener fingerprints are evaluated for all seven pan-Arctic shelf seas and for the interior basins. Particulate and dissolved PCBs were collected via trace-clean protocols on three basin-wide expeditions (AO-01, Beringia-2005, and ISSS-08). Concentrations of the sum of 13 abundant congeners (Sigma(13)PCB) were 0.13-21 pg/L, with higher concentrations in the shelf seas and lower concentrations in the Central Arctic Basin. Trichlorinated PCBs constituted about half of the total loadings in the Eastern Arctic (Beaufort, Chukchi, East Siberian, and Laptev Seas) and in the Central Basin, indicating an atmospheric source. In contrast, hexachlorinated PCBs were more abundant than tri-PCBs in the western sector, suggesting a role also for waterborne transport from regions of heavy PCB consumption in North America and Europe. Finally, the inventory of Sigma(13)PCB in the polar mixed layer of the entire Arctic Ocean was 0.39 ton, which implies that only 0.0008% of historical PCB emissions are now residing in Arctic surface waters.

  • 5. Carrizo, Daniel
    et al.
    Gustafsson, Orjan
    Pan-Arctic River Fluxes of Polychlorinated Biphenyls2011In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 45, no 19, p. 8377-8384Article in journal (Refereed)
    Abstract [en]

    Observations of polychlorinated biphenyls (PCB) concentrations in fluvial surface sediments near the mouths of the six Great Arctic Rivers (GARs; Ob, Yenisey, Lena, Indigirka, Kolyma, and Mackenzie) were combined with annual dissolved organic carbon (DOC) and particulate organic carbon (POC) loadings and hydraulic discharge to estimate the pan-Arctic river flux of PCBs. The highest total-phase fluxes of Sigma(13)PCB were found for the Ob River, with 184 kg/yr and the smallest for the Indigirka River with 3.9 kg/yr. Consistent with a continent-scale trend among the Eurasian GARs of increasing POC concentrations eastward, which is extending to the North American Mackenzie River, a general shift in the estimated PCB partitioning from dissolved to particle-associated flux was found toward the east. Pentachlorinated and hexachlorinated PCBs constituted the majority (>70%) of the total PCB fluxes in the Eurasian Rivers. In contrast, trichlorinated and tetrachlorinated congeners were the most abundant in the Mackenzie (approximate to 75%). The total Sigma(13)PCB fluxes from the pan-Arctic rivers are here estimated to be similar to 0.4 tonne/yr. This is geochemically consistent with the inventory of total PCBs in the Polar Mixed Layer of the entire Arctic Ocean (0.39 tonne) and about a factor 2 less than two new estimates of the PCB settling export to Arctic subsurface waters. Hence, the yearly Great Arctic River PCB fluxes only represent 0.001% of the historical PCB emission into the global environment. To our knowledge, this is the first estimate of circum-Arctic river flux of any organic pollutant based on a comprehensive investigation of the pollutants in several rivers and it contributes toward a more complete understanding of large-scale contaminant cycling in the Arctic.

  • 6. Dickhut, Rebecca M.
    et al.
    Cincinelli, Alessandra
    Cochran, Michele
    Kylin, Henrik
    Aerosol-Mediated Transport and Deposition of Brominated Diphenyl Ethers to Antarctica2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 6, p. 3135-3140Article in journal (Refereed)
    Abstract [en]

    Brominated diphenyl ethers (BDE47, 99, 100, and 209) were measured in air, snow and sea ice throughout western Antarctica between 2001 and 2007. BDEs in Antarctic air were predominantly associated with aerosols and were low compared to those in remote regions of the northern hemisphere, except in Marguerite Bay following the fire at Rothera research station in Sept 2001, indicating that this event was a local source of BDE209 to the Antarctic environment. Aerosol BDE47/100 reflects a mixture of commercial pentaBDE products; however, BDE99/100 is suggestive of photodegradation of BDE99 during long-range atmospheric transport (LRAT) in the austral summer. BDEs in snow were lower than predicted based on snow scavenging of aerosols indicating that atmospheric deposition events may be episodic. BDE47, -99, and -100 significantly declined in Antarctic sea ice between 2001 and 2007; however, BDE209 did not decline in Antarctic sea ice over the same time period. Significant losses of BDE99 and -100 from sea ice were recorded over a 19 day period in spring 2001 demonstrating that seasonal ice processes result in the preferential loss of some BDEs. BDE47/100 and BDE99/100 in sea ice samples reflect commercial pentaBDE products, suggesting that photodegradation of BDE99 is minimal during LRAT in the austral winter.

  • 7. Harner, T
    et al.
    Kylin, H
    Bidleman, T F
    Halsall, C
    Strachan, W M J
    Polychlorinated naphthalenes and coplanar polychlorinated biphenyls in arctic air1998In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 32, no 21, p. 3257-3265Article in journal (Refereed)
    Abstract [en]

    Concentrations of polychlorinated naphthalenes (PCNs) are reported for the first time in arctic air. The data represent combined air samples from the Barents Sea (n = 2), eastern Arctic Ocean (n = 10), Norwegian Sea (n = 2), and two land-based monitoring stations at Alert, Canada (n = 5), and Dunai Island in eastern Siberia, Russia (n = 3). Values for Sigma PCN (pg m(-3)) were 6-49 for shipboard samples and 0.3-8 for land-based stations and were dominated by the 3-Cl and 4-Cl homologues, which accounted for 90-95% of the total mass. Average values for Sigma PCB (pg m(-3)) for the shipboard samples were 126, 24, and 75 for the Barents Sea, eastern Arctic, and Norwegian Sea, respectively. Three-dimensional 5-day air parcel back-trajectories arriving at the ship at 850 and 925 hPa suggested that elevated PCB and PCN concentrations for shipboard samples originated in Europe. Concentrations (fg m(-3)) of coplanar PCBs in artic air were 3-40 (PCB 77) and 0.3-8 (PCB 126)-about an order of magnitude lower than in urban air. Higher concentrations of PCB 77 and PCB 126, 347 and 5.0 (fg m(-3)), respectively, were found in the Barents Sea for two samples with elevated Sigma PCBs. The proportion of coplanar PCBs to Sigma PCBs was within the range of values reported for Aroclor and Clophen mixtures. The 2,3,7,8-TCDD toxicity of the air samples was assessed in terms of the TEQ (dioxin toxic equivalents) contribution of mono-ortho PCBs (congeners 105, 114, 118, 156), non-ortho (coplanar) PCBs (congeners 77 and 126), and dioxin-like PCNs for which toxic equivalent factors have been determined. The results show a 13-67% TEQ contribution of PCNs in arctic air, and it is concluded that further investigation of this compound class is merited.

  • 8. Harner, T
    et al.
    Kylin, H
    Bidleman, T F
    Strachan, W M J
    Removal of alpha- and gamma-hexachlorocyclohexane and enantiomers of alpha-hexachlorocyclohexane in the eastern Arctic Ocean1999In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 33, no 8, p. 1157-1164Article in journal (Refereed)
    Abstract [en]

    Atmospheric concentrations of hexachlorocyclohexanes (HCHs) have declined over the last two decades, and the Arctic Ocean is now eliminating HCHs through degradation, volatilization, and advective outflow. Air and water samples were collected on a cruise of the eastern Arctic Ocean in July-September 1996 for HCHs and enantiomers of alpha-HCH. Mean concentrations of alpha- and gamma-HCH in air were 37 and 17 pg\textbackslashm(-3). Back trajectories indicated that the concentration and proportion of gamma-HCH increased when air parcels passed over Eurasia where lindane (gamma-HCH) is currently used. Mean concentrations in surface water (910 pg L-1 alpha-HCH; 270 mu g L-1 gamma-HCH) were lower than those in the western Arctic. The enantiomer ratio, ER = (+)-alpha-HCH /(-)-alpha-HCH, averaged 0.87 +/- 0.06 (n = 21) in surface water and decreased with depth. Microbial degradation rates of HCHs were estimated using vertical profiles of ER and concentration, surface water data from 1979 (21), and the “ventilation” age of water at a particular depth (22). Microbial rate constants were 3-10 times greater than those for hydrolysis. Half-lives for (+)-alpha- HCH, (-)-alpha-HCH, and gamma-HCH were 5.9, 23.1, and 18.8 years, respectively. Water-air fugacity ratios (f(w)/f(a)) indicated that alpha-HCH was near steady state, while gamma-HCH was undergoing deposition to the ocean. ERs of alpha-HCH in air (0.95 +/- 0.03, n = 16) were slightly less th a n racemic, showing the contribution of volatilization to the boundary layer.

  • 9. He, Peng
    et al.
    Aldahan, Ala
    Possnert, Goran
    Hou, Xiaolin
    Temporal Variation of Iodine Isotopes in the North Sea2014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, no 3, p. 1419-1425Article in journal (Refereed)
    Abstract [en]

    Monitoring temporal variability of I-129 in the North Sea, a relatively large reservoir of radioactive discharges from the nuclear fuel reprocessing facilities, is vital for the environmental situation in the region. New information on concentration levels and distribution of I-129 and I-127 and their species forms (iodide and iodate) are gained here through sampling of surface water in 2010. The results show generally large spatial and temporal (compared to data from 2005) fluctuations of total I-129 and I-127, and iodide and iodate. In samples south of 53 degrees N, the level of I-127(-) in 2010 was generally comparable or higher than in 2005. The results also show total I-129 concentrations comparable in the south, but 2-8 times lower in the north, to the analyses made in 2005. Different from total I-129, the I-129(-)/(IO3-)-I-129 values in the northern part were 2 times higher in 2010 than values observed in 2005. These variations in total I-129 and I-127 and their species are related to coastal water offshore propagation and surface currents that are linked to long-term and seasonal climatic changes over the North Atlantic and North Sea. Inventory estimation shows that >90% of I-129 resides in the Southern and German Bights, which also suggests negligible contribution from the Sellafield facility discharges when compared with that from the La Hague. Variability in discharge rate from La Hague may also affect the distribution patterns of I-129 in the North Sea on the monthly scale.

  • 10.
    Jantunen, Liisa M.
    et al.
    Environm Canada, Ctr Atmospher Res Expt, Egbert, ON L0L 1N0, Canada..
    Helm, Paul A.
    Univ Toronto, Toronto, ON M5S 3E5, Canada..
    Kylin, Henrik
    Norwegian Inst Air Res, Polar Environm Ctr, NO-9296 Tromso, Norway.;Swedish Univ Agr Sci, Dept Environm Assessment, SE-70507 Uppsala, Sweden..
    Bidlemant, Terry F.
    Environm Canada, Ctr Atmospher Res Expt, Egbert, ON L0L 1N0, Canada..
    Hexachlorocyclohexanes (HCHs) in the Canadian archipelago. 2. Air-water gas exchange of alpha- and gamma-HCH2008In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 42, no 2, p. 465-470Article in journal (Refereed)
    Abstract [en]

    Air and water were sampled in the Canadian Archipelago during summer on the Tundra Northwest 1999 (TNW-99) expedition and air was sampled at Resolute Bay (1313), Nunavut, to determine the gas exchange of a-and gamma-hexachlorocyclohexanes (HCHs) and the enantiomers of alpha-HCH. Air concentrations of Sigma HCH during TNW-99 and at RB were similar, averaging 55 and. 53 pg m(-3), respectively. The net gas exchange direction was volatilization for alpha-HCH and near equilibrium or deposition for gamma-HCH, whereas actual fluxes depended on the fraction of open water. Enantiomer fractions, EF = (+)/[(+) + (-)] of alpha-HCH in air sampled from shipboard were significantly correlated to those in surface water for events with >90% open water, but were closer to racemic and not correlated to EFs in water for events with 0-50% open water. Levels of alpha-HCH in air at RB averaged 37 9 pg m(-3) from June to early July, and EFs were close to racemic (0.496 +/- 0.004). In mid-July the ice pack broke up around RB. From this point through August, air concentrations increased significantly to 53 +/- 5 pg m(-3), and the mean EF decreased significantly to 0.483 +/- 0.009. Air concentrations of gamma-HCH at RB did not differ significantly before (8.0 +/- 3.7 pg m(-3)) and after (6.6 +/- 0.76 pg m(-3)) ice breakup. Results show that a-HCH enantiomers are sensitive tracers for following the impact of ice cover loss on gas exchange in the Arctic.

  • 11.
    Jantunen, Liisa
    et al.
    Environment Canada, Canada.
    Wong, Fiona
    Stockholm University.
    Gawor, Anya
    Environment Canada.
    Kylin, Henrik
    Linköpings universitet, Tema Miljöförändring.
    Helm, Paul
    Ontario Ministry of the Environment, Canada.
    Stern, Gary
    University of Manitoba, Canada.
    Strachan, William
    Environment Canada, Canada.
    Burniston, Deborah
    Environment Canada, Canada.
    Bidleman, Terry
    Umeå University.
    20 Years of Air-Water Gas Exchange Observations for Pesticides in the Western Arctic Ocean2015In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, no 23, p. 13844-13852Article in journal (Refereed)
    Abstract [en]

    The Arctic has been contaminated by legacy organochlorine pesticides (OCPs) and currently used pesticides (CUPs) through atmospheric transport and oceanic currents. Here we report the time trends and air−water exchange of OCPs and CUPs from research expeditions conducted between 1993 and 2013. Compounds determined in both air and water were trans- and cis-chlordanes (TC, CC), trans- and cis-nonachlors (TN, CN), heptachlor exo-epoxide (HEPX), dieldrin (DIEL), chlorobornanes (ΣCHBs and toxaphene), dacthal (DAC), endosulfans and metabolite endosulfan sulfate (ENDO-I, ENDO-II, and ENDO SUL), chlorothalonil (CHT), chlorpyrifos (CPF), and trifluralin (TFN). Pentachloronitrobenzene (PCNB and quintozene) and its soil metabolite pentachlorothianisole (PCTA) were also found in air. Concentrations of most OCPs declined in surface water, whereas some CUPs increased (ENDO-I, CHT, and TFN) or showed no significant change (CPF and DAC), and most compounds declined in air. Chlordane compound fractions TC/(TC + CC) and TC/(TC + CC + TN) decreased in water and air, while CC/(TC + CC + TN) increased. TN/(TC + CC + TN) also increased in air and slightly, but not significantly, in water. These changes suggest selective removal of more labile TC and/or a shift in chlordane sources. Water−air fugacity ratios indicated net volatilization (FR > 1.0) or near equilibrium (FR not significantly different from 1.0) for most OCPs but net deposition (FR < 1.0) for ΣCHBs. Net deposition was shown for ENDO-I on all expeditions, while the net exchange direction of other CUPs varied. Understanding the processes and current state of air−surface exchange helps to interpret environmental exposure and evaluate the effectiveness of international protocols and provides insights for the environmental fate of new and emerging chemicals.

  • 12. Klaminder, Jonatan
    et al.
    Hammarlund, Dan
    Kokfelt, Ulla
    Vonk, Jorien E.
    Bigler, Christian
    Lead Contamination of Subarctic Lakes and Its Response to Reduced Atmospheric Fallout: Can the Recovery Process Be Counteracted by the Ongoing Climate Change?2010In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 44, no 7, p. 2335-2340Article in journal (Refereed)
    Abstract [en]

    Can a climate-triggered export of old contaminants from the soil alter the lead (Pb) contaminant burden of subarctic lakes? To address this question, we reconstructed the pollution history of three high latitude lakes situated in a region where a recent climatic shift has occurred. Dated sediment records were used as archives of past Pb inputs to the lakes, where the difference in the 206Pb/207Pb ratio between atmospheric contaminants (206Pb/207Pb ratio <1.16) and geogenic Pb in the catchment soil (206Pb/207Pb ratio >1.22) were used to trace fluxes of Pb contaminants. Lead contaminants were found in sediments deposited since Roman times. A significant export of Pb from the soil contaminant pool is indicated in two of the lakes surrounded by near-shore permafrost soils. Here, levels of Pb contaminants and 206Pb/207Pb ratios of sediments deposited after the 1970s appear not to have been strongly affected by the ≥90% reduction in atmospheric deposition rates and increasing 206Pb/207Pb ratios of atmospheric Pb since the 1990s. We concluded that soil processes stimulated by the ongoing climate change at high latitudes might work counteractive to efforts to reduce contaminant levels in subarctic lakes.

  • 13. Mastromonaco, Michelle G. Nerentorp
    et al.
    Gardfeldt, Katarina
    Langer, Sarka
    Dommergue, Aurelien
    Seasonal Study of Mercury Species in the Antarctic Sea Ice Environment2016In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 50, no 23, p. 12705-12712Article in journal (Refereed)
    Abstract [en]

    Limited studies have been conducted on mercury concentrations in the polar cryosphere and the factors affecting the distribution of mercury within sea ice and snow are poorly understood. Here we present the first comprehensive seasonal study of elemental and total mercury concentrations in the Antarctic sea ice environment covering data from measurements in air, sea ice, seawater, snow, frost flowers, and brine. The average concentration of total mercury in sea ice decreased from winter (9.7 ng L-1) to spring (4.7 ng L-1) while the average elemental mercury concentration increased from winter (0.07 ng L-1) to summer (0.105 ng L-1). The opposite trends suggest potential photo or dark oxidation/reduction processes within the ice and an eventual loss of mercury via brine drainage or gas evasion of elemental mercury. Our results indicate a seasonal variation of mercury species in the polar sea ice environment probably due to varying factors such as solar radiation, temperature, brine volume, and atmospheric deposition. This study shows that the sea ice environment is a significant interphase between the polar ocean and the atmosphere and should be accounted for when studying how climate change may affect the mercury cycle in polar regions.

  • 14. Ndungu, Kuria
    et al.
    Zurbrick, Cheryl M
    Stammerjohn, Sharon
    Severmann, Silke
    Sherrell, Robert M.
    Flegal, A. Russell
    Lead sources to the Amundsen Sea, West Antarctica2016In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851Article in journal (Refereed)
    Abstract [en]

    The global prevalence of industrial lead (Pb) contamination was exemplified decades ago by the predominance of anthropogenic Pb in samples of Antarctic surface ice and in Southern Ocean surface waters. Decreases in environmental Pb contamination corresponding with the near global phase-out of leaded automobile gasoline beginning in the 1970s have since been observed. Measurements of Pb concentration in snow and ice core samples from Antarctica show that recent fluxes of industrial Pb to Antarctica have similarly declined. Here, we present measurements of Pb concentrations and isotopic compositions in seawater and surface sediments from the Amundsen Sea continental shelf including the Amundsen Sea Polynya. Both sets of measurements show that most (~60 - 95%) of the Pb at our sites, at the time of sampling, is natural in source: that is, derived from the weathering of Antarctic continental rocks. These fluxes of natural Pb then become entrained into polynya waters either from sediment re-suspension or from the transport of sediment-laden glacial melt waters to the polynya.

  • 15.
    Park, Kihong
    et al.
    Gwangju Inst Sci & Technol GIST, Sch Environm Sci & Engn, Natl Leading Res Lab, Kwangju 500712, South Korea..
    Kim, Gibaek
    Gwangju Inst Sci & Technol GIST, Sch Environm Sci & Engn, Natl Leading Res Lab, Kwangju 500712, South Korea..
    Kim, Jae-suk
    Gwangju Inst Sci & Technol GIST, Sch Environm Sci & Engn, Natl Leading Res Lab, Kwangju 500712, South Korea..
    Yoon, Young-Jun
    Korea Polar Res Inst, Inchon 406840, South Korea..
    Cho, Hee-joo
    Gwangju Inst Sci & Technol GIST, Sch Environm Sci & Engn, Natl Leading Res Lab, Kwangju 500712, South Korea..
    Ström, Johan
    Stockholm Univ, Dept Appl Environm Sci, SE-11418 Stockholm, Sweden..
    Mixing State of Size-Selected Submicrometer Particles in the Arctic in May and September 20122014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, no 2, p. 909-919Article in journal (Refereed)
    Abstract [en]

    Aerosols have been associated with large uncertainties in estimates of the radiation budget and cloud formation processes in the Arctic. This paper reports the results of a study of in situ measurements of hygroscopicity, fraction of volatile species, mixing state, and off-line morphological and elemental analysis of Aitken and accumulation mode particles in the Arctic (Ny-Alesund, Svalbard) in May and September 2012. The accumulation mode particles were more abundant in May than in September. This difference was due to more air mass flow from lower latitude continental areas, weaker vertical mixing, and less wet scavenging in May than in September, which may have led to a higher amount of long-range transport aerosols entering the Arctic in the spring. The Aitken mode particles observed intermittently in May were produced by nucleation, absent significant external mixing, whereas the accumulation mode particles displayed significant external mixing. The occurrence of an external mixing state was observed often in May than in September and more often in accumulation mode particles than in Aitken mode particles, and it was associated more with continental air masses (Siberian) than with other air masses. The external mixing of the accumulation mode particles in May may have been caused by multiple sources (i.e., long-range transport aerosols with aging and marine aerosols). These groups of externally mixed particles were subdivided into different mixing structures (internal mixtures of predominantly sulfates and volatile organics without nonvolatile species and internal mixtures of sulfates and nonvolatile components, such as sea salts, minerals, and soot). The variations in the mixing states and chemical species of the Arctic aerosols in terms of their sizes, air masses, and seasons suggest that the continuous size-dependent measurements observed in this study are useful for obtaining better estimates of the effects of these aerosols on climate change.

  • 16. Rosèn, Peter
    et al.
    Vogel, Hendrik
    Cunningham, Laura
    Hahn, Annette
    Hausmann, Sonja
    Pienitz, Reinhard
    Zolitschka, Bernd
    Wagner, Bernd
    Persson, Per
    Universally Applicable Model for the Quantitative Determination of Lake Sediment Composition Using Fourier Transform Infrared Spectroscopy2011In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Environmental Science & Technology, Vol. 45, no 20, p. 8858-8865Article in journal (Refereed)
    Abstract [en]

    Fourier transform infrared spectroscopy (FTIRS) can provide detailed information on organic and minerogenic constituents of sediment records. Based on a large number of sediment samples of varying age (0–340 000 yrs) and from very diverse lake settings in Antarctica, Argentina, Canada, Macedonia/Albania, Siberia, and Sweden, we have developed universally applicable calibration models for the quantitative determination of biogenic silica (BSi; n = 816), total inorganic carbon (TIC; n = 879), and total organic carbon (TOC; n = 3164) using FTIRS. These models are based on the differential absorbance of infrared radiation at specific wavelengths with varying concentrations of individual parameters, due to molecular vibrations associated with each parameter. The calibration models have low prediction errors and the predicted values are highly correlated with conventionally measured values (R = 0.94–0.99). Robustness tests indicate the accuracy of the newly developed FTIRS calibration models is similar to that of conventional geochemical analyses. Consequently FTIRS offers a useful and rapid alternative to conventional analyses for the quantitative determination of BSi, TIC, and TOC. The rapidity, cost-effectiveness, and small sample size required enables FTIRS determination of geochemical properties to be undertaken at higher resolutions than would otherwise be possible with the same resource allocation, thus providing crucial sedimentological information for climatic and environmental reconstructions.

  • 17. Salvado, Joan A.
    et al.
    Sobek, Anna
    Carrizo, Daniel
    Gustafsson, Orjan
    Observation-Based Assessment of PBDE Loads in Arctic Ocean Waters2016In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 50, no 5, p. 2236-2245Article in journal (Refereed)
    Abstract [en]

    Little is known about the distribution of polybrominated diphenyl ethers (PBDE)-also known as flame retardants- in major ocean compartments, with no reports yet for the large deep-water masses of the Arctic Ocean. Here, PBDE concentrations, congener patterns and inventories are presented for the different water masses of the pan-Arctic shelf seas and the interior basin. Seawater samples were collected onboard three cross-basin oceanographic campaigns in 2001, 2005, and 2008 following strict trace-clean protocols. Sigma 14PBDE concentrations in the Polar Mixed Layer (PML; a surface water mass) range from 0.3 to 11.2 pg.L-1, with higher concentrations in the pan-Arctic shelf seas and lower levels in the interior basin. BDE-209 is the dominant congener in most of the pan-Arctic areas except for the ones close to North America, where pentaBDE and tetra-BDE congeners predominate. In deep-water masses, Sigma 14PBDE concentrations are up to 1 order of magnitude higher than in the PML. Whereas BDE-209 decreases with depth, the less-brominated congeners, particularly BDE-47 and BDE-99, increase down through the water column. Likewise, concentrations of BDE-71 -a congener not present in any PBDE commercial mixture increase with depth, which potentially is the result of debromination of BDE-209. The inventories in the three water masses of the Central Arctic Basin (PML, intermediate Atlantic Water Layer, and the Arctic Deep Water Layer) are 158 +/- 77 kg, 6320 +/- 235 kg and 30800 +/- 3100 kg, respectively. The total load of PBDEs in the entire Arctic Ocean shows that only a minor fraction of PBDEs emissions are transported to the Arctic Ocean. These findings represent the first PBDE data in the deep-water compartments of an ocean.

  • 18. Sobek, A
    et al.
    Gustafsson, O
    Latitudinal fractionation of polychlorinated biphenyls in surface seawater along a 62 degrees N-89 degrees N transect from the southern Norwegian Sea to the North Pole area2004In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 38, no 10, p. 2746-2751Article in journal (Refereed)
    Abstract [en]

    Surface seawater concentrations of PCBs, relative congener abundance, and possible effects of cold condensation were studied along a transect from the southern Norwegian Sea to the central Arctic Ocean (620degrees N-89degrees N). Large volume samples were collected from an ice breaker using a stainless steel surface seawater intake connected online to an ultra-clean laboratory. Concentrations of all studied PCB congeners, except for trichlorinated PCB 18, decreased with latitude. For instance, PCB 52 decreased from 470 fg L-1 at 62degrees N to 110 fg L-1 at 89degreesN and PCB 180 from 110 to 12 fg L-1. Concentrations in the central Arctic Ocean were on the order of 10-100 fg L-1 for the most abundant congeners. The relative contribution of trichlorinated PCBs to the total PCB concentration increased with latitude, the tetrachlorinated contribution to the total PCBs did not show any correlation to latitude, and the relative contribution of heavier congeners decreased with latitude. This study establishes the occurrence at very low abundances of PCBs in seawater in the central Arctic Ocean and demonstrates a northward concentration decrease. The latitudinal shift in congener pattern is reflecting the relative propensity of the PCB congeners to undergo long-range transport in the Arctic and is consistent with their relative vapor pressures.

  • 19. Sobek, A
    et al.
    Olli, K
    Gustafsson, O
    On the relative significance of bacteria for the distribution of polychlorinated biphenyls in arctic ocean surface waters2006In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, no 8, p. 2586-2593Article in journal (Refereed)
    Abstract [en]

    This study presents the first field observations of polychlorinated biphenyls (PCB) in bacteria in oceanic waters. To contribute to the limited knowledge of what role bacteria play in the dynamics of hydrophobic organic contaminants (HOCs) in surface seawater, PCB concentrations were measured in bacteria (0.2-2 mu m) collected at seven stations in the northern Barents Sea marginal ice zone (MIZ) and the central Arctic Ocean. Concentrations of individual PCB congeners in bacteria were 0.5-5 ng/g oc (organic carbon), which was as high as or higher than PCB concentrations in bulk particulate organic carbon (POC, “phytoplankton”; > 0.7 mu m). Considering the relative biomasses of phytoplankton and bacteria, the amount of PCB in bacteria was generally 5-20% of that in phytoplankton, but at two stations the bacterial biomass contained more PCBs than the phytoplankton pool. This study further showed that efficient PCB uptake in bacteria may be described by an apparent equilibrium partitioning model with linear regressions between the organic-carbon-normalized partition coefficient and the octanol-water partition coefficient (log Kbact-oc-log K-OW).

  • 20. Sobek, Anna
    et al.
    Gustafsson, Orjan
    Deep Water Masses and Sediments Are Main Compartments for Polychlorinated Biphenyls in the Arctic Ocean2014In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 48, no 12, p. 6719-6725Article in journal (Refereed)
    Abstract [en]

    There is a wealth of studies of polychlorinated biphenyls (PCB) in surface water and biota of the Arctic Ocean. Still, there are no observation-based assessments of PCB distribution and inventories in and between the major Arctic Ocean compartments. Here, the first water column distribution of PCBs in the central Arctic Ocean basins (Nansen, Amundsen, and Makarov) is presented, demonstrating nutrient-like vertical profiles with 5-10 times higher concentrations in the intermediate and deep water masses than in surface waters. The consistent vertical profiles in all three Arctic Ocean basins likely reflect buildup of PCBs transported from the shelf seas and from dissolution and/or mineralization of settling particles. Combined with measurement data on PCBs in other Arctic Ocean compartments collected over the past decade, the total Arctic Ocean inventory of Sigma 7PCB was estimated to 182 +/- 40 t (+/- 1 standard error of the mean), with sediments (144 +/- 40 t), intermediate (5 +/- 1 t) and deep water masses (30 +/- 2 t) storing 98% of the PCBs in the Arctic Ocean. Further, we used hydrographic and carbon cycle parametrizations to assess the main pathways of PCBs into and out of the Arctic Ocean during the 20th century. River discharge appeared to be the major pathway for PCBs into the Arctic Ocean with 115 +/- 11 t, followed by ocean currents (52 +/- 17 t) and net atmospheric deposition (30 +/- 28 t). Ocean currents provided the only important pathway out of the Arctic Ocean, with an estimated cumulative flux of 22 +/- 10 t. The observation-based inventory of Sigma 7PCB of 182 +/- 40 t is consistent with the contemporary inventory based on cumulative fluxes for Sigma 7PCB of 173 +/- 36 t. Information on the concentration and distribution of PCBs in the deeper compartments of the Arctic Ocean improves our understanding of the large-scale fate of POPs in the Arctic and may also provide a means to test and improve models used to assess the fate of organic pollutants in the Arctic.

  • 21. Weber, Jan
    et al.
    Halsall, Crispin J.
    Muir, Derek C. G.
    Teixeira, Camilla
    Burniston, Deborah A.
    Strachan, William M. J.
    Hung, Hayley
    Mackay, Neil
    Arnold, David
    Kylin, Henrik
    Endosulfan and gamma-HCH in the Arctic: An assessment of surface seawater concentrations and air-sea exchange2006In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 40, no 24, p. 7570-7576Article in journal (Refereed)
    Abstract [en]

    Arctic seawater concentrations of two currently used pesticides, endosulfan and gamma-HCH, were collated from a variety of cruises undertaken throughout the 1990s up to 2000 for different regions of the Arctic Ocean. Surface seawater concentrations for alpha- and beta-endosulfan ranged from < 0.1 - 8.8 (mean 2.3) pg/L and 0.1 - 7.8 (mean 1.5) pg/L, while gamma-HCH concentrations were similar to 100 fold higher than alpha-endosulfan, ranging between < 0.70 and 894 (mean 250) pg/L. Geographical distributions for alpha-endosulfan revealed the highest concentrations in the western Arctic, specifically in the Bering and Chukchi Seas with lowest levels toward the central Arctic Ocean. In contrast, gamma-HCH revealed higher concentrations toward the central Arctic Ocean, with additional high concentrations in the coastal regions near Barrow, Alaska and the White Sea in northwest Russia, respectively. A fugacity approach was employed to assess the net direction of air-water transfer of these two pesticides, using coupled seawater and air concentrations. For alpha-endosulfan, water - air fugacity ratios (FR) were all < 1 indicating net deposition to all regions of the Arctic Ocean, with the lowest values (0.1 - 0.2) evident in the Canadian Archipelago. Given the uncertainty in the temperature-adjusted Henry’s Law constant (factor similar to 10), it is plausible that equilibrium may have been reached for this compound in the western fringes of the Arctic Ocean where the highest water concentrations were observed. Similarly, FR values for gamma-HCH were generally < 1 and in agreement with other separate studies, although, like alpha-endosulfan, net deposition predominated over the Canadian Archipelago. In the central and eastern regions of the Arctic Ocean, as well as in the two coastal areas of this study, the fugacity ratios for gamma-HCH where similar to 1 indicating conditions approaching equilibrium. The elevated water concentrations and higher FRs in these coastal areas support the assessment that riverine/coastal sources are important for this chemical, but less so for alpha-endosulfan for which air to water transfer during the ice-free summer months is likely to be the major contemporary source to the Arctic. It is recommended that archived extracts of river water be reanalyzed for alpha-endosulfan to confirm this.

  • 22. Xing, Shan
    et al.
    Hou, Xiaolin
    Aldahan, Ala
    Possnert, Goran
    Shi, Keliang
    Yi, Peng
    Zhou, Weijian
    Iodine-129 in Snow and Seawater in the Antarctic: Level and Source2015In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, no 11, p. 6691-6700Article in journal (Refereed)
    Abstract [en]

    Anthropogenic I-129 has been released to the environment in different ways and chemical species by human nuclear activities since the 1940s. These sources provide ideal tools to trace the dispersion of volatile pollutants in the atmosphere. Snow and seawater samples collected in Bellingshausen, Amundsen, and Ross Seas in Antarctica in 2011 were analyzed for I-129 and I-127, including organic forms; it was observed that I-129/I-127 atomic ratios in the Antarctic surface seawater ((6.1-13) x 10(-12)) are about 2 orders of magnitude lower than those in the Antarctic snow ((6.8-9.5) x 10(-1)0), but 4-6 times higher than the prenuclear level (1.5 x 10(-12)), indicating a predominantly anthropogenic source of I-129 in the Antarctic environment. The I-129 level in snow in Antarctica is 24 orders of magnitude lower than that in the Northern Hemisphere, but is not significantly higher than that observed in other sites in the Southern Hemisphere. This feature indicates that I-129 in Antarctic snow mainly originates from atmospheric nuclear weapons testing from 1945 to 1980; resuspension and re-emission of the fallout I-129 in the Southern Hemisphere maintains the I-129 level in the Antarctic atmosphere. I-129 directly released to the atmosphere and re-emitted marine discharged I-129 from reprocessing plants in Europe might not significantly disperse to Antarctica.

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