Organochlorine pesticide residues in inland wetland fishes of Karnataka, India and their implications on human dietary intake.

As part of a larger study assessing contamination status of inland wetlands of India, we evaluated the organochlorine pesticide (OCP) residues in fishes collected from different inland wetlands in Karnataka, India and their suitability for human consumption. Among the OCPs tested, isomers of hexachlorocyclohexane (HCH) were the most frequently detected with β- and γ-HCH as the main pollutants. Average concentration of ∑HCH and ∑DDT ranged from 2.1 to 51.7 μg/kg and below detection level to 12.3 μg/kg respectively. Other organochlorine pesticides such as heptachlor epoxide, dieldrin and endosulphan were found at lower levels. Among various fish species tested, the higher pesticide burden was recorded in Anguilla bicolor bicolour (77.9 μg/kg) and the lower was in Heteropneustes fossilis (2.1 μg/kg). OCPs detected in the present study were well below the tolerance limits recommended for fishes. The calculated daily dietary intake of OCPs in all the species examined was lower than the maximum acceptable dietary intake (ADI) limits prescribed for human consumption. However, continuous monitoring is recommended to facilitate the early identification of risks.