Assessing organochlorine pesticide (OCP) residues in water and fish samples from a small perennial river and associated wetlands of Ganga Basin, India for sustainable management

Worldwide, freshwater ecosystems are facing threat due to environmental hazards and management strategies are needed for sustainability of the resources. The present study focusses on organochlorine pesticide (OCP) residues detected in the water and selected fish samples of catfish and minor carp species (Cirrhinus reba) collected during the experimental sampling of the River Gerua and associated wetlands, which is one of the important tributaries of the Ganga Basin flowing through India–Nepal border. In the water samples, ΣOCPs ranged between 0.018 and 0.235 µg/l (mean 0.11 ± 0.08) and αENDO detected to 0.004 µg/l in the water sample collected from the lower stretch. In the fish muscles, ΣOCPs ranged between 0.006 and 0.255 µg/g (mean 0.09 ± 0.08) and maximum value of αENDO (0.125 µg/g) was detected in Mystus cavasius. The total DDT was detected to 0.096 µg/g in Clupisoma gerua collected from the lower stretch. The study suggests for development of the suitable strategies for managing the environmental hazards and to undertake the appropriate measures to protect the threatened fish and other aquatic organisms.