| Taking Shanghai city as an example, the study analyzed the difference of concentration levels in road dust, soil and leaves besides roads. The reasons and mechanisms of the accumulation characteristics were also been discussed. The result shows that, in a same functional area, road dusts and soils accumulated more PAHs while leaves did less, and the concentrations of PAHs in P. orientalis L.leaves were higher than those in Buxus sinica leaves. Total PAHs concentrations in road dust and soil ranged from 8 992 ng·g-1 to 141 723ng·g-1, averaged in 54 964 ng·g-1, and from 9 306 ng·g-1 to 146 689ng·g-1, averaged in 56 883 ng·g-1, respectively. Total PAHs concentrations in P. orientalis L. leaves and Buxus sinica leaves varied from 2 423 ng·g-1 to 32 883 ng·g-1, with a mean value of 12 983 ng·g-1, from 1 498 ng·g-1 to 19 418 ng·g-1, with a mean value of 7 612 ng·g-1. Among various functional areas, there were significant differences in PAHs concentrations in road dusts and soils while those in leaves were similarly. PAH homologue concentrations in road dusts and soils had significant difference in various functional areas with the priority of high molecular homologues. However, PAH homologue concentrations in leaves were similarly dominated by low molecular homologues. The accumulation characteristics were closely corresponding with the physicochemical property of PAHs and the main accumulation ways of PAHs in multimedia. |
