Aquatic pollution is considered as a major issue due to its detrimental effects on both aquatic and terrestrial organisms including human beings. Several industries are directly discharging the pollutants such as heavy metals into the water bodies without any prior treatments especially in developing countries. Heavy metal such as copper cause toxicity and adverse impact on fish health. The aim of present study was to determine of behavior and 96 hour lethal concentration (LC₅₀) value of copper sulphate for the freshwater fish, Labeo rohita (rohu). The fingerlings of L. ohita with average total length ± standard deviation (SD), 13.843 ± 1.162 cm; average weight ± SD, 24.38 ± 4.516 g were taken in six groups having 10 individual in each. Fish specimens were exposed to copper sulphate as 0, 1, 2, 3, 4, 5 and 6 mg/L for 96 hours after acclimatization. Mortality and behavior of fish was recorded. The irregularity in swimming, loss of balance and excessive body secretions was seen in copper sulphate exposed fish individuals. The lethal concentration value of copper sulphate for the fish, L. rohita was estimated as 1.60 mg/l. The current results provide acceptance limit of maximum quantity of copper for L. rohita. The pretreatment of industrial effluents was recommended before discharge.

Index Terms: Toxicity, copper sulphate, Heavy metal, Fish, Labeo rohita,