Policy adjustment impacts Cd, Cu, Ni, Pb and Zn contamination in soils around e-waste area: Concentrations, sources and health risks

Pollution control policies (PCP) have been implemented in some e-waste dismantling areas in China to curb metal contamination since 2012. We investigated the effects of policy intervention on the concentrations, sources and health risks of heavy metals in soils. Post-implementation, among Cd, Cu, Ni, Pb and Zn, Pb levels declined while the Cd, Cu, Ni and Zn concentrations in soils were not impacted. Changes in their pollution indices and health risks were also similar. After the PCP, the contribution of traffic emission significantly decreased, while natural and industrial contribution increased due to the heighten background input and relocation of small e-waste dismantling workshops. Risk assessment showed that total cancer risk of five metals also slightly increased. Thus, policy intervention might be effective in controlling the release of some metals from e-waste dismantling. However, the performance of control measures varied depending on both source emission and geochemical properties of the metals. This study reveal the ongoing need of stricter supervision, targeted emission reduction and more-effective soil remediation actions to alleviate soil contamination from e-waste dismantling. [Display omitted] •Policy was assessed to gain insight on source, concentration and risk of heavy metals.•Regulation lowered level and health risk of Pb, with little impacts on other metals.•Policy effect varied with geographic characteristic & source emission of metals.•Targeted emission reduction and soil remediation needed to reduce metal pollution