Polychlorinated biphenyl congeners in Antarctic biota from the Barton Peninsula, King George Island

Abstract

Although Antarctica is largely pristine, relatively volatile persistent organic pollutants (POPs) can be carried there by long-range atmospheric transport. Their highly lipophilic and persistent nature allows ready accumulation in organisms and subsequent biomagnifications through the food web. Here, we describe the distribution and concentration profiles of dioxin-like PCB congeners, and estimate transference rates through the food web in various Antarctic organisms. Antarctic organisms from various trophic levels were collected from around Narebski Point and Marian Cove, Barton Peninsula, King George Island, South Shetland Islands between 2007 and 2008. The dioxin-like PCB concentrations were 18.52 pg g-1 in sediments from c. 20m depth in Marian Cove. The mean dioxin-like PCB concentrations were 0.35 ng g-1 in krill, 3.9 ng g-1 in amphipods, 15.1 ng g-1 in silverfish, 4.1 ng g-1 in gentoo penguin, and 1.6 ng g-1 in chinstrap penguin eggs. The higher concentration of dioxin-like PCBs in predators (brown skua and south polar skua) compared with amphipods etc. confirms the importance of biomagnification. The highest transference rates were observed in the link between the highest carnivorous predators (two skua species) and their major prey, penguins and krill. This study is the first to report dioxin-like PCB concentrations and bioaccumulation in various food web levels around Nar˛ebski Point (ASPA No. 171). Further comprehensive studies of contamination, including other POPs and heavy metals, will be conducted in this area.