Lead, cadmium, mercury and selenium in Greenland marine animals

Baseline concentrations of lead, cadmium, mercury and selenium are reported from different tissues in marine organisms from Greenland. Overall, lead levels in marine organisms from Greenland are low, whereas cadmium, mercury and selenium levels are high. Tissue differences are not very distinct for lead, whereas the opposite is the case for cadmium and mercury. Selenium shows an intermediate behaviour in this respect. In general, lead concentrations do not correlate with the age/size of animals, whereas cadmium, mercury and selenium increase with age/size of most species and tissues analysed. No clear conclusions can be drawn in relation to geographical differences in lead, mercury and selenium concentration in Greenland. In general, cadmium levels are higher in Northwest Greenland compared to southern areas. Local differences with increasing cadmium levels from inner fjords to the open sea in stationary species may be of the same order of magnitude as those observed over long distances in Greenland. There is no indication that lead and selenium levels increase in higher trophic levels, although this is clearly the case for cadmium and mercury. In almost all cases lead levels in marine organisms from Greenland are well below the Danish food standard limits, however, a substantial proportion of marine mammals and seabirds in Greenland have cadmium and mercury levels exceeding the Danish standard limits. No food standard limits are given for selenium in food, but in some cases human intake of selenium is estimated to be high.