VARIATIONS OF MERCURY AND SELENIUM CONCENTRATIONS IN ADAMUSSIUM-COLBECKI AND PAGOTHENIA-BERNACCHII FROM TERRA-NOVA BAY (ANTARCTICA) DURING A 5 YEARS PERIOD

Pagothenia bernacchi and Adamussium colbecki specimens have been colle cted in Terra Nova Bay, Ross Sea, Antarctica, from 1987 to 1992. Total and organic mercury and selenium concentrations were measured in the muscular tissue of P. bernacchii and in the soft parts of A. colbecki. Sampling, samples preparation, and analysis were the same for all the specimens, and the temporal variation in concentrations are discussed . Large variations for total and organic mercury contents are found in A. colbecki, while P. bernacchii shows significant interannual differ ences in selenium concentration. However, none of these differences re flect a consistent temporal trend. Medians obtained during the five ye ars in 109 specimens of P. bernacchii are: 0.60 mu g/g dry weight for total mercury, 78% for the percentage of organic mercury, and 3.0 mu g /g dry weight for selenium. Values found in 117 specimens of A. colbec ki are: 0.17 mu g/g dry weight for total mercury, 28% for the percenta ge of organic mercury, and 9.1 mu g/g dry weight for selenium.