Migration and transformation of heavy metals in street dusts with different particle sizes during urban runoff

• Published in: Huanjing kexue Vol. 33; no. 3; p. 810
• Main Authors: He, Xiao-Yan, Zhao, Hong-Tao, Li, Xu-Yong, Lian, Bin, Wang, Xiao-Mei
• Format: Journal Article
• Language: Chinese
• Published: China 01.03.2012
• Subjects: China; Cities; Dust; Environmental Monitoring; Metals, Heavy - analysis; Particle Size; Rain; Vehicle Emissions - analysis; Water Movements; Water Pollutants, Chemical - analysis; China
• ISSN: 0250-3301

The heavy metal pollution in runoff caused by street dust washoff has been an increasingly prominent problem in the context of rapid urbanization in China. Based on measurement of heavy metal contents in street dusts with different particle sizes and an experiment of street dust washoff using simulated rainfall, we analyzed the role of particle size of street dust in heavy metal pollution, and the variation in geometrical forms of heavy metals during street dust washoff. Our results showed that the heavy metal concentration decreased from "static" street dust to "dynamic" runoff particulate in the same diameter particles. Heavy metals in street dust were dissolved and extracted during washoff. The average loss proportion of the five metals (Cr, Cu, Ni, Pb, Zn) were 24.3%, 56.8%, 34.3%, 22.8%, 27.3%, respectively. The loss proportion increased with the decrease of the particle size of street dust. Proportion of extracted form dust was higher in street than that in washoff samples, which suggested some dissolve