Characteristics of Heavy Metal Pollution in the Soil around Lead-Zinc Mining Area

The environmental impact of heavy metal pollution from mining activities is of growing concern. Here we have carried out an environmental geochemical investigation to determine the concentrations of heavy metals (Cd, Pb, Zn, and Cu) in soils in and around lead-zinc mining and zinc smelting areas in Northeastern China, analyze the characteristics of heavy metal contamination and assess pollution level in the area. Cd, Pb, Zn, and Cu in soil were extracted by HCl-HNO₃-HClO₄ and their concentrations determined by atomic absorption spectrophotometers (AAS). The metal concentrations in soil were high, with a maximum of 12.39 mg/kg for Cd, 438.10 mg/kg for Pb, 603.55 mg/kg for Zn, and 91.41 mg/kg for Cu. Geo-accumulation index analysis indicated that the soil had suffered severe pollution of Cd and Pb and medium-level pollution of Cu and Zn. Thus, environmental deterioration from heavy metal pollution need more attentions in the future.