An exhaustive classification for the seasonal variation of organic peaks in the atmospheric fine particles obtained by a gas chromatography/mass spectrometry

Abstract

Abstract For organic compounds in fine particles ( PM 2.5 ), the knowledge on their sources and formation processes are still rather limited because of labile characteristics. To assess the contribution of primary and secondary organic aerosols, it is necessary to utilize the behavior of organic markers. In this study, cluster analysis was applied to the seasonal variations of peaks in chromatogram for unquantitative organic compounds in PM 2.5 obtained by a gas chromatography/mass spectrometry (GC/MS) analysis after derivatization method. We used the PM 2.5 samples collected at Maebashi in Japan for four seasons. Based on cluster analysis, total 115 peaks were divided into nine clusters. The combination effects of the primary and secondary particles transported plume from urban atmosphere were found in two clusters for spring and summer. For dicarboxylic acids, C3 − C5 diacids were in same cluster, whereas C2 and C6 diacids were separated with the other cluster. These results show different trends of secondary formation for dicarboxylic acids. This approach might help to find a group of markers in organic aerosols and to classify potential source of secondary organic aerosols.