Size-dependence of mercury (II) accumulation kinetics in the mosquitofish, Gambusia affinis (Baird and Girard)

Size-dependence of mercury (II) accumulation from water by the mosquitofish, Gambusia affinis was assessed under controlled laboratory conditions. Uptake rates were higher for smaller fish than for larger fish. Mean (±S.D.) uptake rate for mosquitofish exposed to 0.24 μg/L of Hg was 0.32 ± 0.15 μg/g dry wt/day. Uptake rate constants were similar for the Hg (II) and Hg° as reported elsewhere. Both inorganic species (Hg (II) and Hg°) were accumulated faster than methylmercury. Elimination rate constants averaged 0.53∓0.14 per day (mean ± 1 S.D.). No significant size effects on elimination rate constants were detected. Elimination constants were similar to those reported elsewhere for Hg° elimination but larger than those for methylmercury elimination. © 1989 Springer-Verlag New York Inc.