STM Article Repository

Water pollution due to heavy metals is a matter of global concern during recent years. Heavy metals constitute a core group of water pollutants due to their bio-accumulative and non-biodegradable properties. Chromium is the first element in group 6 of periodic table having the atomic number 24. Chromium (III) sulphate (Cr2(SO4)318H2O) was taken in the present investigation to study the acute toxicity and behavioural responses to the fresh water fish Heteropneustes fossilis (Bloch.). The acute toxicity of chromium sulphate to the test fish was determined for 24, 48, 72 and 96 hours. The LC50 values for these periods were 34.3 mg/l, 29.2 mg/l, 22.2 mg/l and 19.4 mg/l by regression equation. The sub-lethal concentration determined during this work was 5.0 mg/l. Chromium (III) sulphate treated fishes exhibited exciting and agonistic behaviour. Restlessness, rapid opercular movement, profused mucous secretions in and around the gills was reported also. Thus, the present investigation reports that the chromium salt has wide range effects on the behaviour of fish.