Effects of acute exposure to bifenthrin on some haematological, biochemical and histopathological parameters of rainbow trout (Oncorhynchus mykiss)

The effect of the pyrethroid, bifenthrin, on rainbow trout (Oncorhynchus mykiss) was assessed based on biochemical, haematological and histopathological examination of fish exposed to Talstar 10 EC pesticide preparation (active substance 100 g/l bifenthrin) at a concentration of 14.7 |ig/l. There was a significant (P < 0.01) decrease in plasma ammonia, and significant (P < 0.01) increase in glucose, creatine kinase, alkaline phosphatase and lactate dehydrogenase. Haematologically, fish showed a significant (P < 0.01) decrease in mean erythrocyte volume, erythrocyte haemoglobin, and band neutrophil granulocytes compared to controls. Degeneration of hepatocytes was observed histologically. The bifenthrin-based Talstar 10 EC pesticide preparation was therefore classified as a substance strongly toxic to fish.