POPs in Antarctic ecosystems: is climate change affecting their temporal trends?

Abstract

Climate change is affecting Antarctica and the Southern Ocean and effects have been already reported for the abiotic compartments of the ecosystems, e.g. ice loss and iceberg calving. Global warming can alter also the distribution of persistent organic pollutant (POPs) both at a global scale and in the Antarctic Region, due to their physical-chemical characteristics. Effects of climate changes have been already reported on feeding behaviour and reproductive process of organisms. Another consequence for organisms includes the POP bioaccumulation. Here we review the literature reporting the linkage between recorded effects of climate changes and POP bioaccumulation in resident marine Antarctic species (fish and penguins). Notwithstanding Antarctica is a final sink for persistent contaminants due to the extreme cold climate, a general decreasing POP trend has been observed for some POPs. Their concentrations in biota are reported to be linked to ice melting and large iceberg calving; the peculiar marine Antarctic ecosystems and the pelagic-benthic coupling may also contribute to alterations in the bioaccumulation processes. These effects are similar in polar regions, although the comparison with the Arctic biota is not possible due to the lack of data in the Antarctic Region. It remains an open question if the POP amount accumulated in the Antarctic ecosystems is decreasing or not.