Polycyclic aromatic hydrocarbons in traffic soil and Pinus needles of Beijing, China

Abstract

This study was conducted to examine the impact of vehicular traffic on the contamination status of urban traffic sites in Beijing with respect to polycyclic aromatic hydrocarbons (PAHs). The soil and Pinus pinea needle samples were collected at 12 sites on Three Ring Road in Beijing, China, from July 2009 to March 2010. Total PAH concentrations at traffic sites ranged from 113.86 to 2226.24 ng g -1 with an average value of 658.71 ±742.41 ng g -1 in soil samples and 112.03 to 2016.80 ng g -1 with an average value of 680.29 ±485.61 ng g -1 in needle samples. The PAH pattern was dominated by two- and three-ring PAHs (contributing>80% to the total PAHs) at all the 12 traffic sites. Seasonal variations of PAHs compounds indicated the PAHs concentrations in autumn and winter were higher than those in spring and summer due to temperature effects. This work indicates that the low ring PAHs were the major profile at the roadside of a busy street with heavy traffic in Beijing.