Ecological Risk Assessment of Heavy Metals in the Vicinity of Tungsten Mining Areas, Southern Jiangxi Province

A field survey was performed to investigate the metals contamination in the vicinity of tungsten mining areas. Ten sampling sites alongside perennial wind direction were selected for soil collection and heavy metal contents determination, include Cr, Cu, Zn, Pb, As, Cd, and W. Horizontal and vertical distribution characteristics of metals were performed. Geo-accumulation and potential ecological risk of soil samples were discussed for a description of risk assessment. The results showed that the mean concentrations of all metals in soil samples exceeded the background value of Jiangxi background. The heavy metal contents in vertical profiles revealed the surface accumulation of Cd, W, and Pb, while, As increased as soil depth increased. The geo-accumulation index shown the highest pollution level of W and followed by Cd. Single ecological risk factor (Eri) figured out that the contamination degree followed the sequence of Cd>As>W>Zn>Pb>Cr>Cu. Furthermore, the potential ecological risk index (RI) was calculated for risk level assessment, and Cd takes account the most contribution in surface soil, followed by W and As.