Uptake of organic mercury and selenium from food by nordic shrimp Pandalus borealis

Abstract

In an attempt to improve our understanding of the transfer process of organic mercury (mainly methyl mercury) from the prey to the consumer, the uptake of mercury in edible muscle of shrimps, Pandalus borealis, from contaminated mussels used as food supplies was studied. Shrimps bioaccumulated rapidly mercury in their abdominal muscle when submitted to a highly contaminated diet (6 μg Hg g^?1) but biomagnification was not observed and Hg concentration in shrimps never exceeded 1.8 μg g^?1. The assimilation efficiency during the uptake period was estimated to about 42% When shrimps received moderately contaminated diet (2.5–2.9 μg Hg g^?1), a two-stage bioaccumulation process was observed in which mercury concentration began to increase in shrimp muscle after 15 days of contaminated diet and at the end of the experiment it seemed to level off. This process can be represented by a two-compartment conceptual model in which mercury rs first eliminated and/or accumulated in the compartment 1 (digestive organs) and then transferred to the compartment 2 (abdominal muscle) following a mechanism and under conditions not yet clearly understood. The use of selenium biologically incorporated into the diet had no apparent effect on the uptake of mercury