The chemical composition of fine and coarse particles in relation with the Asian Dust events

摘要

The distribution patterns of the particulate matter (PM) and the associated elements were investigated from Seoul, Korea during spring 2001. The results of our measurements were analyzed to explain the behavior of metallic components by comparing their compositions mainly in terms of between Asian Dust (AD) and non-AD (NAD) period and between fine and coarse particle fraction. The computation of enrichment factor (EF) indicated that the magnitude of EF values for most hazardous metals during the AD period were even smaller than the NAD counterpart. The existence of low EF values during the AD period may be ascribable to the excessive input of crustal components like Al accompanied by the AD event. In accordance with this finding, the effects of the AD events were also reflected in diverse manners, when assessed by the concentration ratios of a given element for both AD/NAD period and fine-to-coarse (F/C) fraction. Results of this comparative analysis generally suggest that AD events are prominent sources for major crustal components in the fine particle fraction of PM. In addition, comparison of our measurement data with those obtained within the Korean peninsula and in the near-by Asian areas indicates that the metallic distribution patterns of the study area may be affected more sensitively by anthropogenic signatures. The results of our analysis, if investigated in relation with air mass movement patterns by means of the back-trajectory analysis, demonstrate consistently that the PM data measured during the study period can be closely tied with the signatures of both AD events and anthropogenic processes.