Pollution level and health risk assessment of heavy metals in PM_2.5, Shanghai

PM_2.5 and its heavy metal concentrations from May to October, 2012 in Putuo District, Minghang District and Chongming Island, Shanghai, were investigated to identify the pollution characteristics and health risks. The PM_2.5 concentrations ranged from 13.66 μg·m^-3 to 143.52 μg·m^-3, and its concentrations in Putuo and Minhang were higher than those in Chongming Island. Additionally, the PM_2.5 concentrations exceeded the national standard II (24 h average concentration, 75 μg·m^-3) in May, September and October, 2012. The results also showed that the temporal variation of heavy metal concentrations was consistent with that of PM_2.5. The concentrations of Cd, Cu, Pb and Zn in Chongming were lower than those in Putuo and Minhang, while the Cr concentrations were higher in Chongming. These 5 kinds of heavy metal had the greatest risk for the health of adult male, followed by adult female, the health risk was minimal for children and adolescent. Among them, the risk indexes of Cd and Cr were higher than those of Cu, Pb and Zn.