Distribution and health risk assessment of organochlorine pesticides (OCPs) in industrial site soils: A case study of urban renewal in Beijing, China

A field survey was conducted in a contaminated industrial site of southern Beijing, China to investigate the contents and distribution of the organochlorine pesticides (alpha-, beta-, gamma-, delta w25-HCH, p,p'-DDT, p,p'-DDE, p,p'-DDD and o,p'-DDT) in the profiles of soil, and a health risk assessment was carried out with CaITOX multimedia exposure model. Results showed that mean concentrations of total hexachlorocyclohexane isomers (HCHs) and total dichlorodiphenyltrichloroethane isomers (DDXs) in soils were in the range of 13.20-148.71 mg/kg, and 3.02-67.43 mg/kg, respectively. Organochlorine pesticides (OCPs) content peaked in the surface and declined in soil profile with depth. The amounts of HCHs in three profiles of soil were larger than DDXs. Composition analysis indicated that there was a trend of degradation of OCPs in the site, but the mean of HCHs and DDXs concentration were over the state warning standard limit (HCHs, 0.50 mg/kg; DDXs, 0.50 mg/kg). According to current land use development, health risk assessment with CaITOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways: dermal uptake and inhalation, and the total risk values all exceeded the general acceptable health risk value (10(-6)). The sensitivity analysis indicated that five parameters significantly contributed to total risk.