Studies on triazophos-induced oxidative stress and genotoxicity in freshwater fish Cyprinus Carpio following sublethal exposures

Abstract

Triazophos (TAP), an organophosphorus insecticide, is widely used in agricultural practice for controlling various insect pests. The present research work aimed to elucidate the impact of TAP on the antioxidant status and DNA content of the freshwater fish Cyprinus carpio. The fish were grouped into batches (n=6) and received a sublethal dose of 0.3mg/L for a duration of 1 (E1), 10 (E2), 20 (E3) and 30 days (E4). Another group, devoid of any toxicant, was maintained as the control (C). Changes in the enzymatic threshold of the selected antioxidants and malondialdehyde (MDA) levels suggested the conformation of oxidative stress in the livers of the freshwater fish C. carpio due to TAP exposure. Additionally, comet assays and micronucleus tests performed on the peripheral blood of the fish suggested increased damage in the form of the percentage of tail DNA formation and a high frequency of micronucleus as compared to the control. A positive correlation was seen between the decline in antioxidant activity, the elevation in MDA and the comet length and micronucleus frequency. The study thus highlights the impact of TAP on antioxidant levels in the livers and genotoxicity in the blood of the freshwater fish C. carpio. The findings of the study confirm that the antioxidant status, along with the comet assay and micronucleus tests could be used as tools in determining the potential genotoxicity due to the TAP impact. It is therefore suggested that extensive use of TAP should be avoided as it may contribute to the decline in the C. carpio population in its natural habitats.