Sub-lethal toxicity of alphamethrin on biochemical indices in a freshwater fish, Cyprinus carpio

Abstract

The focus of the study is to evaluate the effects of a pyrethroid pesticide, alphamethrin on freshwater fish Cyprinus carpio. The LC50 of alphamethrin for 96 h was determined as 6 µg/L. For sub-lethal study, 1/10th (0.6 µg/L-Treatment I) and 1/5th (1.2 µg/L-Treatment II) of 96 h LC50 concentration were exposed to C. carpio for 35 days. At each interval period, biochemical responses such as plasma glucose, protein and muscle glycogen were determined. During the study period, plasma glucose level was significantly increased with decrease in plasma protein in both the treatment groups. The muscle glycogen content in the fishes treated with 0.6 µg/L and 1.2 µg/L of alphamethrin were also observed to decrease significantly. The overall study concludes that alphamethrin at sublethal concentration affects the biochemical indices of Cyprinus carpio. The changes in these biochemical indices can be effectively used to monitor the alphamethrin pesticide in the aquatic environment.