Toxicity of cadmium chloride and lead nitrate to Chironomus tentans larvae
Abstract Chironomid larvae form an important link in aquatic food chains. Effluents from textile and pulp mills contain cadmium and lead salts which are dangerous to chironomid larvae, an important fish food. Toxicities of cadmium chloride and lead nitrate were studied under experimental conditions and the mean survival time and LD 100 values were calculated. Results suggest that following poisoning by CdCl 2 the total protein contents of the chironomid larvae decrease. This may diminish the nutritive value of these larvae as fish food. Qualitative analysis of larvae following exposure to CdCl 2 and Pb(NO 3 ) 2 showed that these heavy metals were taken up by the chironomids.