Presence of organochlorine pollutants in fat and scats of pinnipeds from the Antarctic Peninsula and South Shetland Islands, and their relationship to trophic position

Abstract

Antarctica is still considered one of the few pristine areas in the globe. Despite this, several studies have shown phased out organic pollutants are present in several environmental abiotic and biological compartments. This study, based on blubber and fecal samples collected from five species of Antarctic pinnipeds, assessed the relationship between organochlorine pesticide (OCs) levels and trophic characterization using stable isotope analysis (δ13C and δ15N). The prevailing pollutants found in blubber were hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), Heptachlor and Aldrin (0.84–564.11 ng g−1 l.w.). We also report a high presence of HCHs, Endrin, Dichlorodiphenyltrichloroethane (DDTs) and Methoxychlor (4.50–363.86 ng g−1 d.w.) in feces suggesting a detoxification mechanism. All the species tend towards high trophic positions (3.4–4.9), but with considerable variation in trophic niche and organochlorine pesticide concentrations per sampling site. This finding suggests that differences in pesticide levels in individuals are associated to foraging ecology.