Measurement and source identification of polycyclic aromatic hydrocarbons (PAHs) in the aerosol in Xi'an, China, by using automated column chromatography and applying positive matrix factorization (PMF)
Authors: Tomoaki Okuda a,*, Kazuki Okamoto a, Shigeru Tanaka a, Zhenxing Shen b, Yuemei Han b, Zongquan Huo b
a Department of Applied Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
b Department of Environmental Science and Engineering, Xi’an Jiaotong University, XianNing West Road28#, Xi’an 710049, PR China

Summary
Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds that consist of fused benzene rings. Samples were collected from October 2005 to October 2007 from rooftop of a 15m high building. Soxhelt-Warm extraction method, high performance liquid chromatography, and automated column chromatography were used to separate PAHs. Data was analyzed by positive matrix factorization (PMF) method. Concentrations of PM10, SO2, NO2a, and PAHs in the aerosol samples collected is given in table 1.
The profiles obtained matched with previous works. Factor 1 consists of four ring PAHs and is similar to the profiles of oil combustion in external combustion engines like those of a boiler. Factor 2 resembled with the profiles of biomass burning having 3 to 4 ring PAHs. Factor 3 had high molecular weight PAHs and was found similar to waste incinerator profiles. Factor 4 showed similarity with the profiles obtained from gasoline internal combustion engines. Factor 5 revealed this factor to be similar to coal combustion by the residents of Xi’an. Figure 1 shows the seasonal variation of PAHs from 5 different sources discussed above.


Table 1. Concentrations of PM10, SO2, NO2, and PAHs
 

 
Figure 1. Seasonal Variation of PAHs from 5 sources in Summer and Winter

Reviewer: Aamir Alaud-din
        aamiralauddin@gist.ac.kr