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

A ffield survey was conducted in a contaminated industrial site of southern Beijing, China to investigate the contents and distribution of the organochlorine pesticides (α-, β-, γ-, δ-HCH, p,p′-DDT, p,p′-DDE, p,p′-DDD and o,p′-DDT) in the proffiles of soil, and a health risk assessment was carried out with CalTOX 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 proffile with depth. The amounts of HCHs in three proffiles 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 CalTOX 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 ffive parameters signifficantly contributed to total risk.