Contamination levels for lead, cadmium and mercury in marine gastropods, echinoderms and tunicates

Abstract

As part of a specific monitoring programme, total lead (Pb), cadmium (Cd) and mercury (Hg) concentrations in marine gastropods (common winkle, common whelk, abalone and murex), echinoderms (purple sea urchin and black sea cucumber) and tunicates (an ascidian species) were investigated by the French National Reference Laboratory (NRL) for trace elements in foodstuffs of animal origin. These elements were analysed by atomic absorption spectrometry in order to evaluate the safety of these species for human consumption. The highest levels of Hg and Cd were found in murexes, 0.185 mg kg −1 and 0.853 mg kg −1, respectively; whereas the highest level of Pb was detected in ascidians (0.505 mg kg −1). Hg and Pb concentrations were always below the maximum levels set by the European legislation (0.5 mg Hg kg −1 and 1.5 mg Pb kg −1 wet mass) and for Cd, only 2 samples of murex (2.09 ± 0.42 mg kg −1 and 2.33 ± 0.46 mg kg −1) exceeded the maximum level set by French legislation of 2.0 mg kg −1 wet mass.