Comparative study of the cadmium and mercury kinetics between the short-lived gastropod Viviparus georgianus (Lea) and pelecypod Elliptio complanata (Lightfoot), under laboratory conditions.
A laboratory study of the cadmium and mercury accumulation and elimination kinetics was conducted on the pelecypod Elliptio complanata (Lightfoot) and the short-lived gastropod Viviparus georgianus (Lea), according to age-classes. Preliminary results (metal concentration vs time of exposure) have demonstrated that uptake of Cd and Hg, in the two molluscs studied, follow a biphasic pattern, whereby a steady state is reached after approximately 16 days' exposure and then accumulation increases again for the rest of exposure period. The elimination of the two metals is also characterized in a biphasic way: fast excretion for the first four days followed by a slower depuration for the rest of exposure time. A two-compartment bioaccumulation model has been used to described the different kinetic parameters: (1) the rate constant for depuration; (2) the rate constant for uptake; (3) the theoretical bioconcentration factor extrapolated to steady-state conditions; and (4) the biological half-life of the metals.
Tessier
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Laboratoire de Recherche sur les Communautés Aquatiques, Université du Québec à Trois-Rivières, Département de Chimie-Biologie, C.P. 500, Trois-Rivières (Québec), Canada.
Vaillancourt
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G
Pazdernik
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