Title: HCH and DDT Residues in Indian Soil: Atmospheric Input and Risk Assessment
Abstract: Hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) are the two major organochlorine pesticides (OCPs) extensively used in India for more than half a century. Although these OCPs were banned or severely restricted for use, residues of these pesticides still persist in soil and other environmental media and are of public health concern. This chapter deals with the usage, consumption, and atmospheric input of HCH and DDT in Indian soil and estimated the Incremental Lifetime Cancer Risk (ILCR) due to chronic exposure. Occurrence of pesticidal residues in Indian soil is due to both past and ongoing usage of these compounds. β-HCH and p,p′-DDE dominated the HCH and DDT residue levels in soil. Therefore, their re-emission from soil to air is occurring from the historically contaminated sites as well as dissipation due to ongoing application of DDT for vector control. Volatilization fluxes revealing the fate of these OCPs and soil contamination levels from India can be a valuable contribution to add in the ongoing persistent organic pollutants (POPs) inventories in compliance with reporting commitments of the Stockholm Convention. Human health exposure based on ILCR suggested that the soil ingestion is an important route of exposure in child than adult which may lead to potential cancer risk from infant stage.