Zinc, cadmium, and lead in livers, kidneys, and feathers of 48 young and adult Atlantic puffins found dead or dying off the coast of Galicia (Northwest Spain) were determined. The most abundant between the three elements was the essential metal zinc, with highest mean levels (173±9mg/kg dry weight) in livers. For the two non-essential metals, the highest mean levels of cadmium were found in kidneys (22.1 ± 1.0 mg/kg dry weight), and of lead in feathers (1.31±0.10mg/kg dry weight). For some birds, concentrations of zinc and cadmium exceeded established risk levels. The concentrations of the three metals were positively cor- related in livers. In kidneys and livers, cadmium levels were correlated. With respect to age, the levels of the three metals in adults were higher than in young animals. Female birds showed significantly higher levels than males. The results are useful for establishing baseline data of the concentrations of the three metals for this species.
The value of birds as bioindicators for monitoring the environmental inorganic elements has been globally recognized. In this context, due to its well-known ecology and population stability, the Northern gannet (Morus bassanus) could be particularly useful. Dead Northern gannets (n = 30) were collected and samples from the liver, kidney, and feathers were taken, dried, mineralized, and finally analyzed via ICP-MS. Metals and metalloids, namely As, Cd, Hg, Pb, and Zn, associated with environmental pollution and toxicity on living organisms, were evaluated. The mean highest concentrations of As, Hg, and Zn were found in the liver (0.916, 7.026, and 89.81 mg/kg dry weight, respectively). For Cd, the kidney showed the highest mean concentration (17.51 mg/kg dry weight), whereas for Pb, this value corresponded to the feathers (0.399 mg/kg dry weight). Significant differences were found between the age classes in terms of contaminant concentrations, with the adults exhibiting higher metal levels. This difference was significantly relevant for Pb and Hg, where the effect of age was observed for all the considered tissues. When considering the effect of gender, no significant differences were observed, in agreement with similar studies performed in other geographical regions. Finally, positive correlations between the concentrations of Hg and Pb in the feathers and in the liver (r = 0.688, p < 0.001 and r = 0.566, p < 0.001, respectively) were observed, as well as between the feather and kidney concentrations (r = 0.685, p < 0.001) indicating the possibility to use feathers, a non-invasive biomonitoring tissue, for better understanding Hg and Pb exposure in seabirds.