Source identification and risk assessment of heavy metals in road dust of steel industrial city (Anshan), Liaoning, Northeast China

Abstract

The purpose of the study was to acquire the source and evaluate the risk posed by heavy metals in road dust of steel industrial city (Anshan), Liaoning, Northeast China. Potential ecological risk index (RI), pollution index (PI) and geo-accumulation index (Igeo) were applied to evaluate the heavy metal pollution level, and the carcinogenic risk (RI) and hazard index (HI) were calculated to estimate the human health risk. The geographic information system maps clearly reveal the hot spots of heavy metal spatial distribution. Principle component analysis (PCA) and cluster analysis (CA) classified heavy metals into three groups. The metal Zn and Pb originate from the traffic emission, while Cd, Cr, Fe, Mn, Ni and Sb primarily come from industrial activities. These two pathways were the major source of heavy metals pollution by positive matrix factorization (PMF). The Igeo and PI values of heavy metals were decreased in the following order: Cd > Sb > Zn > Fe > Pb > Cu > Cr > Sn > Mn > Ni. The RI index showed the heavy metals were moderate to very high potential ecological risk. The HI values for children and adults presented a decreasing order of Cr > Pb > Ni > Cu > Cd > Zn. The HI also predicted a possibility of non-carcinogenic risk for children living in urban areas in comparison with adults.