DOI: 10.5176/2251-2489_ BioTech14.43
Authors: B. Siva Prasad, P. Sankar Ganesh
Abstract: Extensive application of pesticides in agriculture and allied fields has resulted in global contamination of the environment. Chlorpyrifos is one of the widely used organophosphate pesticides in agriculture across the globe. Indiscriminate use of chlorpyrifos results in its entry into water bodies thereby hampering the aquatic flora and fauna including fishes. Studies addressing the effect of chlorpyrifos in fishes like Catla catla are scarce in the literature. Therefore, current study was designed to assess the effect of chlorpyrifos in fresh water fish Catla catla by semi static method. The median lethal concentration (LC50) of chlorpyrifos in fish was determined by probit analysis. Evaluation of locomotory behavior of fish exposed to median lethal concentration of chlorpyrifos and subsequent recovery up to 12 days was carried out by video tracking. The locomotory behavior of fish was correlated with acetylcholinesterase (AChE) activity in the brain of fish. It was found from the results that chlorpyrifos was highly toxic to fish at LC50 of 0.0416±0.004 mg/L for 96h. Exposure of fish to LC50 chlorpyrifos resulted in 80% reduction in velocity of swimming of fish and its significant recovery at the end of 12th day. The maximum AChE inhibition (95±3%) was observed in brain of fish exposed to 0.0416±0.004 mg/L of chlorpyrifos. Recovery pattern of fish exposed to chlorpyrifos exhibited correlation with activity of acetylcholinesterase. This study can help in ascertaining the biomarker in environmental monitoring and in risk assessment of chlorpyrifos in aquatic ecosystem.
Keywords: Chlorpyrifos; Catla catla; acetylcholinesterase; LC50; biomarker