Determination of PM2.5-bound polyaromatic hydrocarbons and their hydroxylated derivatives by atmospheric pressure gas chromatography-tandem mass spectrometry.

A new method for the determination of 19 polyaromatic hydrocarbons (PAHs) and 12 hydroxy-polyaromatic hydrocarbons (OHPAHs) in fine particulate matter (PM2.5) was developed using atmospheric pressure gas chromatography-tandem mass spectrometry (APGC-MS/MS). Better sensitivity was achieved by APGC-MS/MS than conventional liquid chromatography or gas chromatography coupled with mass spectrometry. The method detection limits (< 0.4 pg m-3 for PAHs and < 0.076 pg m-3 for OHPAHs), recoveries (67.7-120%), repeatability (RSD of 0.9-19.1%) and linearity (R2 > 0.99) were obtained for the analysis of PM2.5 samples. The content profile of 19 PAHs and 12 OHPAHs were successfully obtained in 55 PM2.5 samples collected from two major Chinese megacities, Taiyuan and Guangzhou, in both summer and winter by this method. Based on the concentrations, possible emission sources for the pollutants were also identified.