Characteristics of particulate matter and metals in the ambient air from a residential area in the largest industrial city in Korea

This study investigated the characteristics of mass size distributions and metallic elements in the airborne particulate matter from an urban, residential area in Ulsan, Korea. Daily PM samples were trapped on glass fiber filters from April to August 2008 using an eight-stage cascade impactor. The identified concentrations of PM1.0, PM2.5 and PM10 were 18.5, 27.6 and 50.5 μg/m3, respectively. Light metals (Na, K, Ca, Mg, Al) and two heavy metals (Fe and Zn) were detected in high concentrations in the coarse particles, while the remaining heavy metals (Cd, Cr, Cu, Ni, Mn and Pb) were found mainly in the fine particles. The crustal elements were found in higher concentrations in the spring and the anthropogenic elements were found in high concentrations in the summer. Chromium was found to have the highest excess cancer risk in a risk evaluation using an Integrated Risk Information System. In the results of an analysis of the enrichment factors, Cd, Pb, Cu and Zn were found to be very highly enriched, and Cr and Ni were found to be highly enriched. Factor analysis permitted the identification of three source groups (dust and vehicle exhaust, Cu smelting and oil combustion) for the fine particles and two source groups (industrial emissions and crustal traffic sources) for coarse particles.