Identification of zones contaminated with phthalates and polycyclic aromatic hydrocarbons by concentrations in gridded soil with 1/6° latitude by 1/4° longitude resolution: a case study of Zhejiang, China

Phthalic acid esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) are of global concern because of their serious environmental impacts. The identification of zones contaminated with PAEs and PAHs in the soil is urgently needed to provide a basis for land use and remediation. Zhejiang Province was used as a typical example to identify contaminated zones by measuring the concentrations of PAEs and PAHs in gridded soil with a 1/6° latitude by 1/4° longitude resolution. Based on the concentrations and spatial distributions of PAEs and PAHs in superficial soil in Zhejiang, the estimation of inventory, and the assessment of ecological risk, the contaminated zones and possible sources of these two groups of pollutants were identified. High spatial variability of PAE concentrations in the surface soils was observed in Zhejiang Province. The areas with high PAE concentrations were in the middle region of Zhejiang where highly urbanized and industrialized. The spatial distribution of PAH in the surface soil of Zhejiang appeared to be uneven. High PAH concentrations in the soil of Zhejiang were mainly measured in plains areas and can be linked to the development of industry and multiple emission sources. PAE pollution mainly originated from centralized plastic manufacturing, plastic product use, and plastic waste recycling. PAH contamination was linked to the combustion of fuels in vehicle engines and industrial discharge from a cluster of low-capacity boilers. These results can provide a database and reliable reference information for land use and remediation in other agroindustrial ecotone areas.