Carbonaceous and ionic compositions of PM10, PM2.5 and PM1 in Seoul during 2007-2008

The size of aerosol is determined by their origin, chemical and physical composition. The goals of this research were to measure the mass concentration of PM10, PM2.5, and PM1 and their soluble ions and organic matters to understand their chemical property in each size. Here we describe measurements of PM10, PM2.5, and PM1 in Seoul, South Korea during 2007-2008. Daily-integrated aerosol samples were collected using Cyclone. Water-soluble ions, elemental carbon (EC) and organic carbon (OC) were analysis. In mass concentration, Asian dust plume was well distinguished in PM10 while anthropogenic pollution plume in PM1. The variation of PM2.5 was similar to that of PM10. Major water-soluble ions such as SO42- and NH4+ were dominant in PM1. but NO3- didn’t show clear size dependency. EC(OC) concentrations of PM2.5, and PM1 were 4.61(9.72), 4.04(9.08) μg/m3. EC and Organic matter (OM=OC×1.4) constituted 49.9% and 15.8% of PM1 mass, respectively. In Asian dust event, non-identified matters were increased. Monthly mass fraction of PM10, PM2.5, and PM1 were correlated with the wind direction. Portion of Carbonaceous and non-identified matters were increased in February and May when dominant westerly wind, which is mainly due to long-range transport. On the other hand, water-soluble ions increased in September when dominant easterly wind.