[Pollution characteristics and source identification of atmospheric particulate matters n-alkanes in Baoding City].

Organic matter has been a very important component in the ambient particulate matter of big cities in China. In order to investigate the mass concentrations and sources of the organic matter which are adsorbed in ambient particulate matters in the industry cities of Hebei province, aerosol samples were collected with Anderson sampler during Sep. 2009 to Aug. 2010, in Baoding city, Hebei province. The concentration of n-alkanes was determined via GC-MS. About 66.7% of the daily average concentrations of fine particulate matters were higher than the 24-hour average threshold value of class II standard of the ambient air quality standard (GB 3095-2012, 75 microg.m-3). About 96% of the daily average concentrations of inhalable particles were higher than 150 microg.m-3)(GB 3095-2012). The total concentration of n-alkanes was in the range of 111.23-979.81 ng.m-3 with an average of 264.2 ng.m-3. The n-alkene homologues from C14 to C32 were detected with different peak carbon numbers ranging from 20 to 27 in different seasons. In summer, the peak carbon number was 27, while it was C20, C21 or C22 in winter and spring. The CPI values were 0. 97, 1. 24, 0. 92 and 0. 86 in spring,summer, autumn and winter, respectively, with an average of 1.01. These results indicated that the incomplete combustion of fossil fuel and vehicle emissions was the main resource of n-alkanes in winter and spring, and the high plant waxes were playing a major role in summer and autumn. The primary sources were anthropogenic activities all year round.