MERCURY AND SELENIUM IN HARBOR PORPOISE (PHOCOENA-PHOCOENA) IN NORWEGIAN WATERS

Concentrations of mercury and selenium have been determined in liver a nd kidney of 92 harbor porpoises (Phocoena phocoena) caught along the Norwegian coast. The hepatic and renal mercury concentrations ranged f rom 0.26 to 9.9 and 0.15 to 3.5 mug g-1, respectively, whereas the cor responding selenium concentrations ranged from 0.74 to 14.2 and 0.60 t o 8.6 mug g-1, respectively. No significant differences in mean concen trations of mercury and selenium were found between females and males within the same age classes. However, the concentrations were positive ly correlated with age. The present results revealed a decreasing merc ury concentration gradient from south to north along the Norwegian coa st. In all age classes, a significant, positive correlation between th e concentrations of mercury and selenium was found in both liver and k idney, the molar mercury-to-selenium ratio being 0.9660 and 0.2151, re spectively. Implications of these findings for the biochemical and tox icological behavior of mercury and selenium in the harbor porpoise are considered.