Heavy metal pollution and human health risk assessment for exposure to surface soil of mining area: a comprehensive study

Abstract

The contaminated soil by mining activities could be transported through the erosive effect of wind. In this study, human health risk was assessed for exposure to heavy metals (Cu, Zn, Cd, Pb) present in surface soil of Irankouh zinc–lead mine, (the nearest mine to Isfahan, Iran) as one of the main dust storm sources. The effect of improper mining waste and tailings management in the Irankouh zinc–lead mine was not deeply investigated. Thus, 65 surface soil samples were collected (mining and residential area) and subjected into chemical analyses, then various assessment approaches were conducted on the obtained data. It was found that the mean concentrations of Zn (1035.2 mg kg−1, SD = 563.7), Cd (2.53 mg kg−1, SD = 1.1), and Pb (281.7 mg kg−1, SD = 115.6) were higher in the study area than in the Earth’s crust. Results of enrichment factor (EF) represented high enrichment with the mean values for Cd (5.75), Zn (7.29), and Pb (4.42) in the study area. The considerable ecological risk (RI = 497.95) and high contamination degree (mCd = 11.83) obtained in this study implicated the potential of high health risk in the mining area. Moreover, the results of multivariate analysis techniques revealed a high interrelation between Pb, Zn, and Cd and their common anthropogenic origin in the residential area. All the calculated HI values were higher than one indicated probable adverse effect on human health due to the mining activities. In general, the proper waste management of Irankouh zinc–lead mine should be planned and performed to reduce its environmental adverse effects.