Determination of Sulfur and Oxygen Containing Polycyclic Aromatic Hydrocarbons in Inhalable Particulate by Gas Chromatography-Mass Spectrometry

Aromatic compounds in inhalable particulate were extracted under ultrasonic agitation and extracts were separated by chromatographic column packed with silica gel and alumina. The aromatic fraction was detected by gas chromatography-mass spectrometry coupled with capillary column. On the basis of mass chromatogram and characteristic fraction ions, NIST library searching and retention indices, qualitative analysis of eighteen sulfur and oxygen containing polycyclic aromatic hydrocarbons were performed. They are mainly composed of aromatic heterocycles with 3—4 rings, such as dibenzothiophenes, benzonaphthothiophenes and dibenzofurans. The quantitative analysis results with internal standard showed the concentration of these compounds in urban border site and suburban site was 0.23—5.05ng/m 3 and 0.04—1.27ng/m 3,respectively. The former concentration was 2.8—10.8 times higher than the latter. The concentration of parent aromatic heterocycles was much higher than that of alkyl substituted derivatives, which attributing to fossil fuel (mainly coal) combustion process.