Relative toxicity of technical grade and formulated carbaryl and 1-naphthol to, and carbaryl-induced biochemical changes in, the fish Cirrhinus mrigala

Abstract In a study on the relative toxicity of technical grade material and formulations of carbaryl and its primary degradation product (1-naphthol), to the fish Cirrhinus mrigala , 1-naphthol was found to be the most toxic followed by technical grade carbaryl, 85% wettable powder and 50% WP; the calculated 96-h LC 50 values (with the 95% confidence limits in parentheses) were, respectively, 1·46 (1·3 to 1·6), 2·5 (1·9 to 3·2), 2 mg litre −1 carbaryl for 96 h, the protein metabolism was significantly altered in the brain, gills, kidney and muscle, the glycogen content of the liver was significantly increased and the lipid content of the brain was significantly lowered.