Interspecific and intraspecific variation in organochlorine pesticides and polychlorinated biphenyls using non-destructive samples from Pygoscelis penguins

As humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where they can bioaccumulate in the biota. Penguins are exposed to POPs mainly through their diet, which they partially eliminate via feathers. Species of the genus Pygoscelis occur around Antarctic continent and its surrounding regions, and can act as indicators of contaminants that reach the continent. Here, we report OCP and PCB levels in feathers of male and female penguins of P. adeliae, P. antarcticus and P. papua from King George Island, South Shetland Islands, Antarctica. Interspecific, sex- and body-size-related differences were investigated in the contamination profiles of PCBs and OCPs. Feather samples were collected from adult penguins (n = 41). Quantification of compounds was performed by gas chromatography-tandem mass spectrometry. The three Pygoscelis species presented similar contamination profiles, with higher concentrations of dichlorodiphenyltrichloroethane (∑DDT; 1.56-3.82 ng g^-1 dw), lighter PCB congeners (∑PCB: 11.81-18.65 ng g^-1 dw) and HCB (hexachlorobenzene: 1.65-4.06 ng g^-1 dw). Amongst the three penguin species, P. antarcticus had lower and P. papua higher concentrations of most of the compounds identified. We found interspecific differences in POPs accumulation as well as sex differences in POP concentrations. Our data indicate a small but significant positive correlation between body size and the concentrations of some compounds. Despite the overall low concentrations found, this study increases knowledge of the occurrence of POPs in Antarctic penguins, thereby reinforcing concerns that Antarctica, although remote and perceived to be protected, is not free from the impact of anthropogenic pollutants.