Source identification and health impact of PM2.5 in a heavily polluted urban atmosphere in China

Positive matrix factorization (PMF) was applied to identify the types of PM2.5 sources and corresponding mass contributions to PM2.5 mass concentrations using PM2.5 measurements obtained from Dec. 2007 to Oct. 2008 in Jinan, which is a highly polluted city in China. The reconstructed mass concentrations from six sources matched the observations, and the resolved sources constituted 98.91% of the PM2.5 mass concentrations. Secondary sources, the major source contributor, accounted for 55.15% of PM2.5 mass concentration, while several other sources, including coal burning (20.98%), soil dust (9.30%), motor vehicles (6.06%), biomass burning (4.55%), and industry (2.87%), contributed a total of 43.76%. The non-carcinogenic risk estimates showed the elemental risk for Mn, Co, S and Cr were high, with values larger than 0.1 being observed for the three groups. The total elemental risk in Jinan for the three groups was higher than 1, and the largest risk was present for children between the age of 6-12 followed by that for children between 2 and 6 years of age, indicating that citizens in Jinan, particularly children, faced more serious potential non-carcinogenic health risks.