Characteristics and Risk Assessment of 16 Metals in Street Dust Collected from a Highway in a Densely Populated Metropolitan Area of Vietnam

The present study focused on investigating the contamination and risk assessment for 16 metals in street dust from Ha Noi highway, Ho Chi Minh City. The results indicated that the concentrations of metals (mg/kg) were found, in decreasing order, to be Ti (676.3 +/- 155.4) > Zn (519.2 +/- 318.9) > Mn (426.6 +/- 113.1) > Cu (144.7 +/- 61.5) > Cr (81.4 +/- 22.6) > Pb (52.2 +/- 22.9) > V (35.5 +/- 5.6) > Ni (30.9 +/- 9.5) > Co (8.3 +/- 1.2) > As (8.3 +/- 2.5) > Sn (7.0 +/- 3.6) > B (5.7 +/- 0.9) > Mo (4.1 +/- 1.7) > Sb (0.8 +/- 0.3) > Cd (0.6 +/- 0.2) > Se (0.4 +/- 0.1). The geo-accumulation index (I-geo) showed moderate contamination levels for Pb, Cd, Cu, Sn, Mo, and Zn. The enrichment factor (EF) values revealed moderate levels for Cd, Cu, Mo, and Sn but moderate-severe levels for Zn. The pollution load index of the heavy metals was moderate. The potential ecological risk (207.43) showed a high potential. Notably, 40.7% and 33.5% of the ecological risks were contributed by Zn and Mn, respectively. These findings are expected to provide useful information to decision-makers about environmental quality control strategies.