Ecological risk and early warning of soil compound pollutants (HMs, PAHs, PCBs and OCPs) in an industrial city, Changchun, China.

Abstract

Soil ecological risk caused by compound pollutants is a topic that deserves increasing attention, and soil risk early warning is a more in-depth discussion on this topic. In this study, we collected soil samples from Changchun, a typical industrial city, and determined the contents of 13 heavy metals (HMs) (0.00mg kg-1-6380mgkg-1), 16 polycyclic aromatic hydrocarbons (PAHs) (0.00mg kg-1-27.7mgkg-1), 7 polychlorinated biphenyls (PCBs) (0.30μg kg-1-168μgkg-1), and 8 organochlorine pesticides (OCPs) (0.00mg kg-1-4.52mgkg-1). The soil ecological risks of compound pollutants were assessed. The results showed that PAHs were the greatest risk pollutants, followed by PCBs and HMs, and OCPs were the smallest risk pollutants. Most of the ecological risks of compound pollutants were classified as "moderate severity" level according to the (contamination severity index) CSI evaluation criteria. With the help of modern industrial economic theory, through the analysis of the annual accumulation of pollutants, it is possible to predict the future pollutant content in Changchun, and the soil risks could be forewarned. The results showed that if active measures were not taken to reduce the accumulation of PAHs in Changchun soil, the CSI-PAHs would be classified as "ultra-high severity" level in 2035.