Analysis of PM 2.5 Case Study Burden at Chungju City

Fine particles () were collected and analyzed from April 2010 through January 2011 in Chungju to investigate the characteristics of and its ionic species. The annual mean concentrations of , , , and in the particulate phase were 40.84, 7.61, 7.14 and , respectively. concentrations were higher in fall and spring than in winter and summer. The elevated concentrations episodes are the main factor that enhanced the concentrations in the fall. Among the major ionic species showed the highest concentration, followed by and , exhibited higher concentrations during the winter, but and were not showed seasonal variation. The high correlations were found among , , and during all seasons except for spring. The evaluation of backward trajectories and meteorological records show that the highest concentration levels occurred during W-NW weather conditions, which influenced by the emission sources of China area. The low pollution levels generally occurred during E-S weather conditions, which influenced by the East Sea and south of the Yellow Sea. The elevated mass concentrations arouse the concentration of , but no effects on and .