Heavy metals speciation with prediction model for heavy metal mobility and risk assessment in mine-affected soils

Heavy metals from mines affect soil and groundwater, cause aand severely impact on the health of local residents. The soil samples were characterized the for distribution, and by the chemical speciation method , and then estimated the human health risks of the two mine-affected soils after stabilization were estimated. Two extraction techniques (Tessier and Wenzel methods) were applied to fractionate metals, such as arsenic (As) and zinc (Zn), to quantify the chemical status of metals in the soils. The mobility of As and Zn was predicted using ASTM test and sequential extraction (Tessier and Wenzel) methods results. The correlation coefficients of As and Zn mobility prediction using Tessier and Wenzel Fraction 1 were (0.920 and 0.815), respectively. Sum The of fractionsum of fractions (F1+F2+F3) showed the highest correlation coefficients value and F value for mobility prediction of both As and Zn. The hazardous indices (HI) for non-carcinogenic risk and carcinogenic risk (CR) to humans were evaluated according to the pseudo-total concentrations of metal in soils. The CR values of carcinogenic for As were within the ranges from 1.38 × 10^-4 to 1.25 × 10^-3 and 3.71 × 10^-4 to 3.35 × 10^-3 for both Young Dong (YD) and Dea San (DS), respectively. The HI for non-carcinogenic risk was highest for As in the YD (2.77) and DS (7.46) soils, which covered approximately 96 and 84% of HI, respectively. In summary, the contribution of As to risk from heavy metals was dominant.