Distribution and Ecotoxicological Risk Assessment of Persistent Organic Pollutants (POPs) In River Sediments from Delhi, India

Abstract

Persistent organochlorine pesticides (OCPs) like hexachlorocyclohexane (HCH), and dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyls (PCBs) and their ecotoxicological risks were investigated in river bank sediments from Yamuna in Delhi, India. The concentration of HCH, DDT and PCBs ranges between 19.25-731.82 (208.17±20.66) ng g^-1, <0.01-21.21 (1.32±0.36) ng g^-1 and 0.16 to 30.05 (7.69±0.90) ng g^-1, respectively. The composition analysis of HCH and ratio of ±-HCH/-HCH reflects the usage of technical HCH and lindane.  The ratios of DDT and their metabolites indicate historical inputs of DDT or the biotransformation of DDTs in this area. Tri and tetra chlorinated biphenyls (PCB-37 and PCB-44) contributed >80% of the PCBs contamination. Concentration of HCHs, DDT and PCBs did not exceed sediment quality guidelines with the exception of lindane which was above sediment guidelines as lindane formulation are registered in India for use in public health practices to control vector borne diseases.

Keywords: Pesticides, POPs, HCH, DDT, PCBs, River Sediment, India