Exploring Environment Pollution and Risk Assessment of Heavy Metals in Road Dusts from a Typical Steel-Industrial City (Anshan), Northeastern China

Heavy metals in road dusts could cause high potential risk to both human health and environmental safety. This study evaluated chemical fractions, potential leachability, and bio-accessibility of heavy metals (Cr, Cu, Cd, Ni, Pb, and Zn) in road dusts from the steel-industrial city (Anshan), Northeastern China. Sequential extraction analysis revealed that Cr and Ni primarily existed in residual form. The non-residual fraction of heavy metals decreased in the order of Zn (average 57.78%) > Cu (39.16%) > Pb (30.73%) asymptotic to Cd (30.67%) > Ni (19.06%) > Cr (8.7%). The results showed that Cd, Cu, Zn, and Pb, which were extremely concentrated in potentially mobile fractions, had high potential risks. The mobility of Cd and Zn was higher than that of Cr, Cu, Pb, and Ni, which indicated that Cd and Zn posed higher risks. There was a significant relationship between PBET, TCLP-test, and bioavailable parts of sequential extraction, respectively. Redundancy analysis and correlation analysis results indicated that both the basic properties and total heavy metals regulated their toxicity and bioavailability of heavy metals. Thus, the results of health risk assessment to human and the environment can provide a more scientific implication for typical steel industrial urban management.