Source identification and health risk assessment of Persistent Organic Pollutants (POPs) in the topsoils of typical petrochemical industrial area in Beijing, China

Abstract

Thirty-one topsoil samples were collected from the area of the Yanshan petrochemical industries to comprehensively determine the spatial distribution, the possible sources and the potential risks of legacy Persistent Organic Pollutants (POPs) in a typical petrochemical industrial area. The total concentration of 16 PAHs, predominantly originated from the local emission from fuel combustion, ranged from 35.29 to 6120.22ng/g with a mean value of 906.11ng/g. Organochlorine Pesticides (OCPs) originated mainly from the recent inputs and their total concentrations varied from 4.13 to 7215.24ng/g with a mean of 336.13ng/g. Polychlorinated Biphenyls (PCBs) were associated with the usage of commercial products and the total concentrations of 125 congeners ranged from 2.21 to 4008.47ng/g with a mean of 486.12ng/g. Residential Total Lifetime Carcinogenic Risk (TLCR) value, higher than the target excess individual lifetime risk (1×10−6), was calculated to be of 22.6% for PAHs, 16.1% for OCPs and 6. 5% for PCBs respectively. Occupational TLCR, higher than the target excess individual lifetime risk was of 9.7% for PAHs, 6.5% for OCPs and 0% for PCBs respectively. In all sampling sites, non-carcinogenic risks expressed as Total Hazard Quotient (THQ) for PAHs, OCPs and PCBs were always below 1. As a consequence, the carcinogenic and non-carcinogenic risks due to exposure to POPs in soil were very low even in such a typical petrochemical industrial area. In the study, the management and the risk assessment of POPs in a petrochemical industrial area close to a metropolis, were evaluated comprehensively.