Persistent organic pollutants and porphyrins biomarkers in penguin faeces from Kopaitic Island and Antarctic Peninsula

Polychlorinated biphenyl (PCB) levels were determined in the faeces of three Antarctic Peninsula penguin species to assess viability as a non-invasive approach for sampling PCBs in Antarctic biota. These determinations were complemented with stable isotope and porphyrins assessments, and together this methodology determined the role of diet and metabolic disruption in penguins. Up to 60% of the collected faecal samples evidenced low molecular weight PCBs, of which, the more volatile compounds were predominant, in agreement with previous results. The highest PCB levels were reported in the gentoo penguin (Pygoscelis papua; 35.3 ng g^{− 1} wet weight average), followed by the chinstrap (Pygoscelis antarctica; 6.4 ng g^{− 1} wet weight average) and Adélie penguins (Pygoscelis adeliae; 12.9 ng g^{− 1} wet weight average). Stable isotope analyses (δ¹⁵N and δ¹³C) demonstrated that gentoo feeding and foraging habits differed from those of Adélie and chinstrap penguins. A strong positive correlation was found between PCB concentrations and δ¹⁵N, indicating the role of diet on the observed pollutant levels. Porphyrins metabolite levels were also directly correlated with PCB concentrations. These results suggest that PCB levels impair the health of Antarctic penguins.