Affiliations: Department of Environmental Science, Zhejiang
University, Hangzhou 310028, China; E-mail: lzzhu@mail.hz.zj.cn
Abstract: The presence of particulate and vapor PAHs, SO_2 and NOx and other
interrelated conditions (temperature, traffic intensity and wind velocity) were
investigated in the arterial street air of Hangzhou. The concentration of the
nine PAHs in the air was mean to 11.7 µg/m³, and the content of
benzo(a)pyrene was up to 0.108 µg/m³. The contents of PAHs in the
sampling sites were in good relation to the traffic intensity, and would be
also affected by the terrain and meteorological conditions. The occurrences of
PAHs in ambient air were mainly affected by their physical, chemical characters
and temperature. The three- and four-ring PAHs (MW⩽228) mainly existed
in the vapor phase and the five-ring PAHs (MW>228) existed predominately in
the particulate phase. The fraction of vapor PAHs in the total nine PAHs was
84.2% in the air of the sampling sites. In the morning and evening, the
concentrations of PAHs in the arterial street air were higher than that on the
noon and the diurnal variation of PAHs was similar to that of the traffic gas
NOx. A conclusion would be drawn that the major source of PAHs in the arterial
street air was the traffic. And the results indicated that 75% of BaP would
come from traffic source and remaining 25% of BaP would come from non-traffic
source.
Keywords: polycyclic aromatic hydrocarbons, arterial street, air pollution