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(70-93) Effect of zinc on the cadmium accumulation by larvae of the non biting midge Chironomus riparius. Bervoets, Lieven*,1, Blust, Ronny2, 1 Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, Antwerp, Belgium2 Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, Antwerp, Belgium ABSTRACT- The bioavailability of metals to aquatic organisms depends to a large extend on the chemical speciation of the metal and on the presence of competing ions. We studied the uptake and elimination of cadmium by larvae of the midge larvae Chironomus riparius using chemically defined solutions. The effect of different concentrations of the essential metal zinc on the accumulation of the non-essential metal cadmium was investigated. To this, midge larvae were exposed to a range of environmental relevant waterborne cadmium concentrations combined with a range of environmental relevant zinc concentrations. A mixture of stable Cd and Zn with the radiotracers 109Cd and 65Zn was used to follow the same individuals in time by gamma counting. Uptake was followed for one week after which larvae were transferred to tracer free solutions and elimination was followed for another week. From these experiments uptake and elimination rate constants were calculated in order to model the interaction of cadmium and zinc with respect to their accumulation. The accumulation of Cd from a solution containing 0.1 Key words: zinc, cadmium, interaction, accumulation |
M of the metal was already significantly inhibited in the presence of an equimolar concentration of Zn. In contrast, no effect of Cd on Zn accumulation was measured even at a 10-fold concentration of cadmium. Our findings indicate that the presence of waterborne zinc, even at natural levels (e.g. 0.1