Emamectin benzoate (EMB), a macrocyclic lactone insecticide, is extensively used to control insect pests in agriculture and management of parasites in aquaculture farms. Owing to its widespread application, EMB has been detected in soil and water samples throughout the world and raised environmental pollution concerns. Due to itshigh efficiency, persistence, residue and bioaccumulation properties, EMB has caused adverse effects on aquatic organisms. Thus, in the current study, the toxicity of EMB on marker enzymes of zebrafish (Danio rerio) was assessed. Zebrafish were exposed to environmentally relevant concentrations of EMB (0.05, 0.1 and 1.0 mg/L) for a period of 35 days and the changes in the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activity were investigated in the liver and muscle of zebrafish. Results revealed a significant increase in AST and ALT activity in the liver and muscle of EMB exposed fish compared to control group. The alterations of enzymatic activity were found to be higher in liver compared to muscle. Throughout the study period, a dose-dependent elevation of enzyme (AST and ALT) activities was observed. The alterations of transaminases activity can be used as biomarkers for the monitoring of bio pesticides in the aquatic environment.
