The Distribution Characteristics of Elemental Components between Fine and Coarse Particle Fractions in Chongju, Korea

The distribution characteristics of airborne particulate matter (PM) were investigated in terms of the relationships between different constituents (elements) and between different particle ranges (fine vs. coarse) from the city of Chongju, South Korea for approximately a year (October 1995 to August 1996). For the purpose of our study, the elemental compositions of both fine (FP: PM2.5) and coarse particle (CP: PM2.5-10) fractions were determined by proton induced x-ray emission (PIXE). Based on our study, the annual mean concentrations of PM in FP and CP fractions were found to be 41.4 and 29.6 μm-3 , respectively. The major elemental components of CP were found to be in the order of Si, Ca, Al, Fe, K, and Cl, while those of FP were S, Cl, Si, K, and Fe. If the temporal patterns of PM were compared across seasons, the most prominent pattern was found to be a relative depletion in coarse-mode concentrations during the summer's possibly due to efficient wet scavenging. On the other hand, the summiterm for all elements showed consistently a summertime depletion pattern for all particle fractions. Our analysis of the relative relationships between PM and elements confirmed that the contribution of elemental components to PM mass concentrations can differ significantly across different particle size ranges and seasons.