The present study was conducted to examine the potential mechanisms responsible for the distribution of polycyclic aromatic hydrocarbons (PAHs) and their oxygenated derivatives (o-PAHs) in size fractionated particles and their environmental implications. Size-fractionated atmospheric particles were collected at urban Shanghai, China and analyzed for 5 PAHs and 6 o-PAHs. The concentrations of particle-bound n-ary sumation 6o-PAHs (sum of 6 o-PAH congeners, 19.1 +/- 4.5 ng m(-3)) were significantly higher than those of n-ary sumation 5PAHs (sum of 5 PAHs, 9.5 +/- 1.9 ng m(-3)). The size-fractionated distributions of airborne n-ary sumation 5PAHs and n-ary sumation 6o-PAHs displayed bimodal peaks at 0.7-1.1 and 9.0-10.0 mu m. Emission sources and volatility were important factors influencing the size distribution of particle-bound 5 PAHs and 6 o-PAHs. The dry deposition fluxes of particle-bound 6 o-PAHs estimated from the measured data (3087 +/- 467 ng m(-2) d(-1)) were approximately 2 times higher than those of PAHs (1531 +/- 344 ng m(-2) d(-1)), with a total deposition flux of 4618 +/- 743 ng m(-2) d(-1). The relative contributions of particles to dry deposition were also size-dependent, e.g., coarse (aerodynamic diameters (D-p) > 2.1 mu m) particles dominated the dry deposition fluxes of PAHs and o-PAHs. These results highlight the significance of providing a comprehensive understanding of particle size distribution of PAHs and o-PAHs and their implication for dry deposition in China.
[1]Fudan Univ, Dept Environm Sci & Engn, Shanghai 200032, Peoples R China;
[2]Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China
(8.0+极速模式)