Monitoring of PAHs Profiles in the Urban Air of Dalian, China with Active High-volume Sampler and Semipermeable Membrane Devices

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the urban air of Dalian, China was monitored from November 2009 to October 2010 with an active high-volume sampler and a semipermeable membrane device (SPMD) passive sampler. The samples were analyzed for the sixteen US EPA priority monitoring PAHs using GC/MS. The concentrations of ∑PAHs in particle and gas phases ranged from 3.2-90.6 ng m^-3 and 40.8-155 ng m^-3, respectively. The PAHs of 3-4 rings covered 89.2% of the total concentrations (gas phase + particle phase). Furthermore, the gas-particle partitioning phenomena and the results measured from the field versus those predicted by the Junge-Pankow adsorption model, octanol-air partitioning coefficient (K_OA) based absorption model, the absorption into the organic matter plus the adsorption to the soot carbon model using the soot-air partitioning coefficients (K_SA) were discussed in this article. The dominant contributors of PAHs in the gas phase of active samples and SPMD passive samples were similar. The SPMD mainly sequestrated gas phase PAHs. The linear correlation coefficients between C_SPMD and C_air-gas were 0.7316 and 0.7403; C_SPMD and C_air-total were 0.7397 and 0.7409 at Dalian Jiaotong University sampling site and Dalian Meteorological Observatory sampling site, respectively. The quantitative structure-property relationship (QSPR) of the sampling rate of SPMD for PAHs was studied, which can be predicted by the core-core repulsion energy and the energy of the highest occupied molecular orbital of PAH molecules.