Health Risk of Potentially Toxic Elements from Diverse Sources in Urban Road Dust: An Application of Receptor Modeling

Particulate matter (PM) is an air pollutant that poses considerable health risk to the urban population. Contribution of road dust to urban PM is confirmed by many source apportionment studies conducted throughout the world. The scope of this study is to identify the sources of potentially toxic elements (PTEs) in a small Indian city and to examine the health risk posed by each of those sources to both adults and children. Unmix, a multivariate receptor model, is used to identify the various sources of PTEs in the city. The health implications from exposure to different sources of road dust is studied using health risk assessment models. For this, street dust samples are collected from eighteen sampling locations in Vellore city from Tamil Nadu, India, for three seasons. Nine potentially toxic elements are analyzed (Co, Cu, Cr, Fe, Mn, Ni, Pb, Sr and Zn). The study concludes that elements Fe, Pb, Cr and Co pose significant health risk to children. In addition, children are at a higher risk of exposure to PTEs. Health risk from all three sources is found to be higher toward the south of the study region.