Analysis of Organic Compounds in Ambient PM 2.5 over Seoul using Thermal Desorption-comprehensive Two Dimensional Gas Chromatography-time of Flight Mass Spectrometry (TD-GCxGC-TOFMS)

Abstract

Characteristics and advantages of the thermal desorption-comprehensive two dimensional gas chromatographytime of flight mass spectrometry (TD-GCxGC-TOFMS) were discussed and the organic compound’s analysis result was shown for the ambient PM 2.5 sample collected in Seoul, Korea. Over 10,000 individual organic compounds were separated from about 70 μg of aerosols in a single procedure with no sample pre-treatment. Among them, around 300 compounds were identified and classified based on the mass fragmentation patterns and GCxGC retention times. Several aliphatic compounds groups such as alkanes, alkenes, cycloalkanes, alkanoic acids, and alkan-2-ones were identified as well as 72 PAH compounds including alkyl substituted compounds and 8 hopanes. In Seoul aerosol, numerous oxidized aromatic compounds including major components of secondary organic aerosols were observed. The inventory of organic compounds in PM 2.5 of Seoul, Korea suggested that organic aerosol were constituted by the compounds of primary source emission as well as the formation of secondary organic aerosols.