The sublethal effects and accumulation of cadmium in the terrestrial isopod Porcellio laevis Latr. (Crustacea, Isopoda)

This study investigated the sublethal effects of CdSO4 on the terrestrial i sopod species Porcellio laevis and its capacity to accumulate and compartme ntalize cadmium. The ability of P. laevis to discriminate between uncontami nated and CdSO4-contaminated leaves was also studied. It was shown that sub lethal effects in terms of mass changes of exposed isopods occur at cadmium concentrations between 10 and 80 mg/kg. Moreover, P. laevis can be conside red as a so-called macroconcentrator, accumulating and storing cadmium in i ts hepatopancreas tissue. However, the accumulation capacity is not proport ional to the cadmium concentrations in the leaves presented as food, as sho wn by decreasing concentration factors with increasing cadmium concentratio ns in the diet. This is probably an effect of the isopod's ability to discr iminate between different cadmium concentrations in the food, as shown by m eans of feed-choice experiments, in which P. laevis was able to avoid conta minated leaves.