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Abstract: Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjørnøya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjøen. In Lake Øyangen, located only 5 km north of Ellasjøen, levels of these contaminants were significantly lower. δ15N-values were 7–10‰ higher in organisms from Ellasjøen as compared to Øyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjøen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. [Copyright &y& Elsevier]

Lake Ellasjøen and Lake Øyangen are two high Arctic lake ecosystem located on the island Bjørnøya (74°30′ N, 19°00′ E) in the Barents Sea. High levels of persistent organic pollutants (POPs), especially PCB and p,p′-DDE, were found in sediment and biota from Lake Ellasjøen while levels were several times lower in Lake Øyangen. Stable isotope signatures (δ15N) in comparable organisms (e.g. zooplankton, Arctic char) collected from both the lakes were also significantly different. The values of δ15N were 6–10‰ higher in the organisms from Ellasjøen than from Øyangen. In both Ellasjøen and Øyangen, a statistically significant correlation (P<0.05) was found between the levels of PCB and DDT, and δ15N values in organisms indicating enhanced bioaccumulation for higher trophical level lake organisms. As the lakes on Bjørnøya are remote, more than 500 km from any known point source, the presence of POPs is most likely the result of long-range transport of contaminants to the area. The observed higher contaminant concentrations associated with the Ellasjøen ecosystem is attributed to two factors. Ellasjøen is located in the southern, mountainous part of Bjørnøya and it is likely that this area receives more precipitation, and thereby more airborne contaminants, than the flatter areas further north on the island (i.e. the area around Øyangen). In addition, higher δ15N-levels in organisms from Ellasjøen as compared to Øyangen indicate the input of guano from seabirds using the lake as a resting area as an additional source of POPs to Ellasjøen. [Copyright &y& Elsevier]

Abstract: Congener and homologue group patterns of chlorinated paraffins (CPs) in biota can be influenced by different processes, but these are not well studied yet. Short- (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were quantified in liver from Arctic char and seabirds (little auk and kittiwake) collected at Bear Island (European Arctic) as well as in cod from Iceland and Norway. CP concentrations were between 5 and 88 ng/g wet weight (ww) for SCCPs and between 5 and 55 ng/g ww for MCCPs with one exception of 370 ng/g measured in a liver sample from little auk. The SCCP homologue group patterns were compared with those of technical mixtures and of SCCPs present in cod liver from the Baltic Sea. The latter showed a more common SCCP homologue distribution (sum of C11 and C12 >60%) in contrast to cod liver from the Northwest of Europe, which had a high abundance of C10 and C12 congeners. Seabirds from Bear Island contained an equally distributed SCCP homologue group pattern. In Arctic char, the SCCP distribution was closer to technical products, but with a high proportion (average of 18.9%) of C10 congeners. A comparison of C10/C12 ratios confirmed the higher abundance of C10 congeners in samples from higher latitudes. For the first time, MCCPs could be detected in Arctic samples. The average proportion of C14 congeners was 65.8%. The C14/C15 abundance ratio was similar to technical mixtures. High-chlorinated CPs (Cl>7) were also detectable. The average chlorine content of the SCCPs was 61.9% (59.0–63.3%), and that of the MCCPs 55.8% (54.5–57.4%). [Copyright &y& Elsevier]

In Kvalsund, Northern Norway, a permit for submarine mine tailings disposal in Repparfjorden was recently issued for a copper mine with expected operation from 2019. A copper mine was active in the same area in the 1970s and also deposited mine tailings in the fjord. Investigations of the metal binding in the historic and new mine tailings (produced from bedrock in the area) have been undertaken in this study. Acid and base extraction experiments provided desorption curves of mine tailing suspensions as a function of pH (0.5–12.7), and showed that Cu was more easily desorbed in the historic mine tailings. Substantial desorption (>40%) for both historic and new mine tailings occurred at pH values below 3 and above 12. These results combined with metal speciation, showing that the binding of Cu in the sediment changes around pH values 3 and 10, indicate potential for extraction of more Cu from the new mine tailings. Electrodialysis, based on applying an electric field of low intensity to extract metals from polluted soils/sediments, was designed for acidic and alkaline extraction, and in both cases more Cu was extracted than in the pure acid/base extractions, while maintaining low mobilisation of other metals. Electrodialysis can hence be designed to target extraction of Cu while limiting the mobilisation of other metals. [ABSTRACT FROM AUTHOR]

Deposition of large volumes of mine tailings takes place in several Norwegian fjords, but the impacts on marine ecosystems have received relatively little scientific attention. At a 40 + −year old tailing deposition area for a copper mine in the Arctic fjord Repparfjorden, we investigated both short-term colonization of mine tailings-contaminated sediments through a field experiment, and the present faunal state in the old deposit area. Copper-concentrations at the old deposition site were still high (up to 291 mg/kg dry weight (dw)), and exceeded the Norwegian environmental-quality threshold (84 mg/kg dw). Furthermore, copper was identified as a significant structuring factor for the fauna in the fjord, although faunal diversity was relatively high and the community not severely disturbed. In the colonization experiment, experimental boxes filled with defaunated sediment capped with mine tailings were subject to colonization for 15 months. Benthic macrofaunal communities were successfully established in all boxes, but the boxes with tailings showed lower species richness, abundance and biomass than the controls. Mine tailings continue to have local impacts on seafloor communities decades after deposition, and even low levels of metal-rich sediments can affect faunal recruitment. These results have implications for submarine deposition of mining waste and the impacts they have on coastal ecosystems. [Display omitted] • The Arctic fjord Repparfjorden has been subject to Cu-containing tailings disposal • Recovery of mine tailings contaminated sediments has been studied • Mine tailings treatments showed a reduced colonization compared to controls • High levels of Cu prevail in the sediment over 40 years post deposition • The present fauna is diverse, but is still influenced by the previous disposal [ABSTRACT FROM AUTHOR]

Abstract: In order to compare the abilities of arctic and temperate fish to accumulate PCBs we conduct a metabolic analysis to determine how process rates in a mathematical fish contaminant model change with temperature. We evaluate the model by applying the original and adapted models to estimate PCB concentrations in lake trout (Salvelinus namaycush) in Trout Lake, Ontario, Canada, and in arctic char (Salvelinus alphinus) in Lake Øyangen, in the Norwegian high arctic. Modeled concentrations are, for the most part, within 50% of mean measured values and are comparable to the error associated with the fish data. In order to evaluate differences in fish bioaccumulation processes, the model is applied to hypothetical arctic and temperate systems, assuming the same contaminant input values in water and diet. The model predicts that temperate salmonids are able to biomagnify PCBs 6–60% more than arctic salmonids. For all congeners, the lower BMFMAX of arctic fish contribute to their lower concentrations. For congeners with log K ow <6.0, the lower concentrations in arctic fish are also attributed to faster loss due to gill ventilation. Faster growth rates for temperate fish reduce the difference in bioaccumulation for congeners with log K ow >7.0. These processes are controlled by the influence of lipid in the fish and their diet as well as the dependence of growth on temperature. We suggest that fish models originally calibrated for temperate systems may be directly applied to arctic lakes after accounting for the lipid content of the fish and their diet as well as water temperature. [Copyright &y& Elsevier]