Atrazine induced toxic impacts on the survival, behavior, and biochemical aspects of Silver carp (Hypophthalmichthys molitrix)

Abstract

The current research work was conducted to evaluate the acute toxicity of the widely used herbicide, Atrazine on the behavioral responses and biochemical changes in different tissues of Silver carp (Hypophthalmichthys molitrix). Adult fish were exposed to different concentrations of Atrazine for different time periods. Mortality of fish was observed with increase in the concentration of Atrazine and time of exposure. The LC50 of Atrazine for 96 hours was calculated as 13.7µl/L. Fish exposed to Atrazine showed fast swimming, loss of equilibrium and balance, gulping, pale body coloration, and an excess amount of mucous secretion covered the buccal cavity and gills. Total protein contents, antioxidant enzymes including catalase (CAT), peroxidase (POD), and glutathione reductase (GR) and lipid peroxidation (LPO), were measured in the brain, gills, liver, and muscle tissues for biochemical analysis. Atrazine exposure resulted in a significant time-dependent decrease in total protein content in the liver, gills, brain, and muscle tissue of fish compared to the control group. A slight increase was observed in the activities of CAT and POD in the control group, while a significant decrease was observed in the ATZ-treated groups from 24 to 96 h. The glutathione reductase activity was significantly increased in the ATZ treated groups compared to control group. Likely, LPO level also increased in the liver, gills, brain, and muscle tissue in a time-dependent and concentration-dependent manner in ATZ treated groups compared to control group. Concludingly, our results revealed that Atrazine is toxic to fish, alter enzymes and total protein level, and lipid peroxidation level in fish. This harmful effect of Atrazine maybe generalized into environment and reduce the Silver carp population in the natural freshwater bodies.