Atmospheric particulate samples of PM2.5 were collected from the northern suburb of Nanjing in December, 2014, and a LC-MS method was optimized for the determination of aromatic acids in PM2.5; The concentrations of major water-soluble ions, organic carbon and elemental carbon were also determined. The quantification results showed that the average total concentration of five aromatic acids we have determined was (50.01±16.05) ng·m-3, and the average concentrations of terephthalic acid, phthalic acid, trimellitic acid, 4-methylphthalic acid and iso-phthalic acid were (34.54±12.79)、(8.14±3.34)、(2.27±1.39)、(1.68±0.77) and (1.08±0.43) ng·m-3, respectively. The different source apportionments of atmospheric particulate were analyzed by principal component analysis/absolute principal component scores (PCA/APCS) receptor model. The results of source apportionment showed that the main sources of Phthalic acid, Trimellitic acid and 4-methylphthalic acid were mainly secondary transformation, and primary emissions such as vehicle exhaust contributed less to Trimellitic acid; Secondary transformation and biomass burning made the most significant contributions to iso-Phthalic acid and vehicle exhaust contributed less; The sources of Terephthalic acid were primary emissions such as biomass burning and vehicle exhaust.
Keywords: LC-MS; PCA/APCS; benzene polycarboxylic acids; correlation analysis; source apportionment.