[Characteristics and Health Risk Assessment of Metallic Elements in PM Fraction of Road Dust].

In order to analyze and compare the pollution characteristics and risks to human health of metallic elements in the PM fraction of urban road dust (RD) and park road dust (PRD), particles smaller than 2.5 μm were suspended to filters by a re-suspension system and concentrations of Na, Mg, Al, Fe, Cu, Mn, Ni, Sb, Zn, Cd, and Pb were quantified. Results showed that the average concentrations of Cu and Sb in RD were 626 mg·kg and 23 mg·kg, significantly higher than that in PRD (274 mg·kg and 11 mg·kg). This indicated that the elemental composition of RD was influenced by non-exhaust emissions. The geoaccumulation Index (I) of each detected element showed that samples were strongly to extremely contaminated by Cd (4 < I < 5), moderately to strongly contaminated by Cu, Sb, Zn, and Pb (2 < I < 4), and uncontaminated to moderately contaminated by Ni and Mn (I < 1). The hazard index (HI) values of Sb, Pb, Cu, Ni, Zn, and Cd were less than 1 and the incremental lifetime cancer risk (ILCR) values of Ni and Cd were less than 10, indicating that these elements of RD and PRD are not associated with any cancer risks or non-cancer health risks.