Atmospheric Deposition And Gas/Particle Partitioning Of Pahs In The North Yellow Sea

Polycyclic aromatic hydrocarbons (PAHs) were collected around the north Yellow Sea fromJanuary2010to December2010to investigate the composition profiles, dry deposition fluxes and gas/particle partitioning. PAH concentrations were23ng/m3(Zhangzi Island),27ng/m3(Xiaomai Island) and102ng/m3(Laohutan), respectively. Gaseous PAHs were the major part of SPAHs over the north Yellow Sea.Compared with other regions worldwide, the levels of atmospheric PAHs in Laohutan is serious polluted, while Zhangzi Island and Xiaomai Island held less contaminated.Source of PAHs in Zhangzi Island were mainly from petrogenic source, while coal/wood combustion were major sources inXiaomai Island and Laohutan.Combustion of coal, traffic emissions and oil pollutionconstitute the atmospheric PAHs pollution in the North Yellow Sea.The average fluxes of deposition were5327ng/m2d (Zhangzi Island)、6351ng/m2d (Xiaomai Island) and27695ng/m2d (Laohutan), respectively. Thegas PAHs deposition were all based on2+3ring compounds,while the4ring compoundswere dominating in particle PAHs deposition,5+6rings particulate PAHs were significantly higher thangaseous PAHs deposition.With alarger seasonal fluctuation in Xiaomai Island and Laohutan, urban heating coal contributes the atmospheric PAHs.The distribution of PAHs between gas and particles was well correlated with their sub-cooled liquid vapor pressures (p°L). PAHs sampled at a rural site were closer to equilibrium than those collected near urban sites. Both J-P model and Koa model tended to underestimate the sorption for most PAHs, but the absorption model appeared to be more suitable for predicting the particle fraction of PAHs than the J-P model. Absorptive partitioning is believed to be the dominant mechanism.