Trace element levels in harp seal ( Pagophilus groenlandicus) and hooded seal ( Cystophora cristata) from the Greenland Sea. A multivariate approach

Concentrations of the essential trace elements, iron, copper, zinc and selenium and the non-essential elements arsenic, cadmium, total mercury and lead, were measured in the meat, liver and kidney of two species of seals, harp seal ( Pagophilus groenlandicus) and hooded seal ( Cystophora cristata) collected in the Greenland Sea. The spread among the individual seals was considerable. However, multivariate statistics simplified the evaluation of the data. The muscle tissue contained lower levels of the elements than kidney and liver. The kidney and liver tissue were also different, in particular with higher levels of iron in the liver and higher levels of cadmium in the kidney. Species differences were clear in both liver and kidney tissue, with higher levels of most of the elements in the hooded seals, while the harp seals had a higher burden of arsenic in the two tissues. Male hooded seals had higher levels of mercury and selenium than the females in all tissues. For harp seal there was a slight difference between the sexes in the muscle tissue, while no difference was observed in the liver and kidney tissues. The juvenile seals generally had lower levels of the elements in their tissues than the adults, although copper and zinc were higher in the muscles and livers of the juveniles as was iron in the muscles. No correlation between age and trace element levels in the tissues of the adult seals was observed.