Uptake and loss of absorbed dissolved cadmium to Clarias angullaris fingerlings

Abstract

The uptake and loss of dissolved cadmium in media by the African mud fish (Clarias angullaris) fingerlings was studied in water of 25 mg/ L hardness, pH 6.8, at 27 ±2°C in a static test system. The uptake experiments involved exposure of fish to 0.5 and 1.0 mg Cd2+/L test solutions from which the
fish absorbed and retained 1.1011 mg and 1.3060 mg Cd2+/g wet fish weight, approximately 550 and 653 times the recorded normal tissue level, respectively, after 8 days. In the loss experiments, after fourteen (14) days, the fish that had 0.8320 mg Cd2+/g wet weight in the 0.5 mg Cd2+/L test medium reduced the internal concentration to 0.1121 mg Cd2+/g; and in the 1.0 mg Cd2+/L test solution, the reduction is from 0.9820 mg Cd2+/L to 0.1142 mg Cd2+/L wet weight