Occurrence and risk assessment of potentially toxic elements and typical organic pollutants in contaminated rural soils.

The residual levels and risk assessment of several potentially toxic elements (PTEs), phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in rural soils near different types of pollution sources in Tianjin, China, were studied. The soils were found to be polluted to different extents with PTEs, PAEs and PAHs from different pollution sources. The soil concentrations of chromium (Cr), nickel (Ni), di-n-butyl phthalate (DnBP), acenaphthylene (Any) and acenaphthene (Ane) were higher than their corresponding regulatory reference limits. The health risk assessment model used to calculate human exposure indicates that both non-carcinogenic and carcinogenic risks from selected pollutants were generally acceptable or close to acceptable. Different types of pollution sources and soil physicochemical properties substantially affected the soil residual concentrations of and risks from these pollutants. PTEs in soils collected from agricultural lands around industrial and residential areas and organic pollutants (PAEs and PAHs) in soils collected from agricultural areas around livestock breeding were higher than those from other types of pollution sources and merit long-term monitoring.