Baseline heavy metal concentrations in the Antarctic clam, Laternula elliptica in Maxwell Bay, King George Island, Antarctica

Abstract

Baseline heavy metal concentrations were determined in various tissues of the Antarctic soft-shelled clam Laternula elliptica and compared with literature values for temperate and Antarctic bivalve species. Laternula elliptica tends to strongly accumulate most heavy metals with tissue concentrations being comparable to those of mussels and oysters in temperate waters. For the majority of the metals, significantly higher concentrations were measured in the kidney than in any other soft tissues. In addition, Cd concentration in the kidney was positively correlated with that of Zn, Pb and Mn, reflecting the detoxification of the accumulated heavy metals. Thus, these results suggest that L. elliptica can be used as a suitable biomonitor for long-term monitoring of heavy metal contamination in the Antarctic coastal waters. However, habitat sediment is highly elevated with Cu (77 μg g −1 dry weight), which has apparently been derived from lithogenic sources in the surrounding land via meltwater inflow during austral summer. No comparative data, however, are yet available for L. elliptica in other regions, and possible influence of the Cu elevation in this region on the body burden of L. elliptica is discussed in comparison with those of another common Antarctic bivalve, Adamussium colbecki.