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Polychlorinated biphenyls (PCBs) can be used as chemical sentinels for the assessment of anthropogenic influences on Arctic environmental change. We present an overview of studies on PCBs in the Arctic and combine these with the findings from ArcRisk—a major European Union-funded project aimed at examining the effects of climate change on the transport of contaminants to and their behaviour of in the Arctic—to provide a case study on the behaviour and impact of PCBs over time in the Arctic. PCBs in the Arctic have shown declining trends in the environment over the last few decades. Atmospheric long-range transport from secondary and primary sources is the major input of PCBs to the Arctic region. Modelling of the atmospheric PCB composition and behaviour showed some increases in environmental concentrations in a warmer Arctic, but the general decline in PCB levels is still the most prominent feature. ‘Within-Arctic’ processing of PCBs will be affected by climate change-related processes such as changing wet deposition. These in turn will influence biological exposure and uptake of PCBs. The pan-Arctic rivers draining large Arctic/sub-Arctic catchments provide a significant source of PCBs to the Arctic Ocean, although changes in hydrology/sediment transport combined with a changing marine environment remain areas of uncertainty with regard to PCB fate. Indirect effects of climate change on human exposure, such as a changing diet will influence and possibly reduce PCB exposure for indigenous peoples. Body burdens of PCBs have declined since the 1980s and are predicted to decline further., Environmental Science and Pollution Research, ISSN:0944-1344, ISSN:1614-7499

This article provides a synthesis of the latest observational trends and projections for the future of the Arctic. First, the Arctic is already changing rapidly as a result of climate change. Contemporary warm Arctic temperatures and large sea ice deficits (75% volume loss) demonstrate climate states outside of previous experience. Modeled changes of the Arctic cryosphere demonstrate that even limiting global temperature increases to near 2 °C will leave the Arctic a much different environment by mid-century with less snow and sea ice, melted permafrost, altered ecosystems, and a projected annual mean Arctic temperature increase of +4 °C. Second, even under ambitious emission reduction scenarios, high-latitude land ice melt, including Greenland, are foreseen to continue due to internal lags, leading to accelerating global sea level rise throughout the century. Third, future Arctic changes may in turn impact lower latitudes through tundra greenhouse gas release and shifts in ocean and atmospheric circulation. Arctic-specific radiative and heat storage feedbacks may become an obstacle to achieving a stabilized global climate. In light of these trends, the precautionary principle calls for early adaptation and mitigation actions.

Results of the EU ArcRisk project on human health impacts in the Arctic owing to climate-induced changes in contaminant cycling are summarized in the context of their policy application. The question on how will climate change affect the transport of selected persistent organic pollutants (POPs) and mercury, both to and within the Arctic has been addressed, as well as the issue of human health impacts of these pollutants in the Arctic in relation to exposed local populations. It was concluded that better characterization of primary and secondary sources of POPs and more accurate quantification of current and future releases of POPs from these sources are needed for better prediction of environmental exposure to these contaminants and interpretation of monitoring data. Further improvement of fate and transport modeling in the physical environment is necessary in order to consider in the models not only the relatively well studied direct effects of climate change (e.g., changes in temperature, ice and snow cover, precipitation, wind speed and ocean currents) on contaminants fate and behavior but also indirect effects, e.g., alterations in carbon cycling, catchment hydrology, land use, vegetation cover, etc. Long-term environmental monitoring of POPs (at multiple sampling stations within and outside the Arctic and at regular sampling intervals facilitates temporal trend analysis) and measurements of concentrations in human milk and blood plasma are needed. Finally, more information should be gathered on the human health effects of newly identified POPs, such as perfluorooctanesulfonic acid (PFOS), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and other substances with POP-like characteristics, particularly the effects on very young (including fetus) and elderly subgroups of the human population. The ArcRisk developed methodologies and tools that can be used in further studies to resolve various uncertainties already defined in the analysis of climate change impacts on POPs and mercury behavior and effects in the Arctic. The ArcRisk project has also developed very valuable databases that can be regarded as a starting point in further studies.

Increasing demands on resources in the marine area are compromising the future viability of the marine environment and in recent years the need to pursue new approaches for a sustainable use of our ...