Oxidative, biochemical and histopathological alterations in fishes from pesticide contaminated river Ganga, India

The river Ganga basin accommodates large scale of agricultural activities, where large quantities of pesticides are applied. To assess the biological impact of pesticide residues that are continuously entering in the water body, biomarkers are common approach in bio-monitoring study as early warning signals to pollutants. In the present study qualitative and quantitative analyses of gill and liver histopathological and the biochemical parameters were determined in Rita rita and Cyprinus carpio. The difference in the histopathology and oxidative stress responses emphasize the response of selected fishes to the presence of contaminants in the water. Sloughing of lamellar epithelium and their disruption, dilated vessels, lamellar fusion, smooth muscle hypertrophy in the gill and necrosis, Vacuolation in hepatocytes, inflammation and distorted arterial walls were seen in the liver. The biochemical parameters were the main contributors to discriminate the changes in the fish physiology. In conclusion, the gill and liver histopathological responses, although not reflecting specific contaminants, but can be used as biomarkers of environmental contamination.