Effects of city buildings on content and distribution of polycyclic aromatic hydrocarbons in adjacent soil

Sixteen priority control polycyclic aromatic hydrocarbons (PAHs) were analyzed in twenty surface soil samples collected from the plinth or aproll edges of the building (B) and 5-meter sites away from the building (B-5), to discuss the impacts of urban buildings on the level and distribution of PAHs from the surrounding soil. The results showed that the concentration of PAHs ranged from 824 to 8960 ng/g in soil at B, with an average of 2649 ng/g, PAHs in B-5 varied from 673 PAHs in to 1706 ng/g with an average of 1297 ng/g which were significantly lower than that of site B. The distribution profile of PAHs was mainly dominated by 4~5 ring PAHs in the study area. Fl, Pyr, InP and BghiP in soil were dominant species both at B and B-5 and accounted for 48% and 45% of total mass PAHs, respectively. HJ-5, AJ, AJ-5, EB-5 and TC-5 were in the moderate degree of pollution (600~1000 ng/g), and the others were categorized heavily polluted (>1000 ng/g) by reference to Maliszewska-Kordybach soil standard. Soil TOC exhibited the trend of enrichment at B relative to at B-5, and there was no clear correlation with PAHs. BaA, Chry, B(b+k)F, BaP, InP, and DahA were major contributor to TEQBaP concentration. The source apportionment showed that soil PAHs at B and B-5 are mainly originated from coal, gasoline and diesel combustion, and PAHs at B-5 might be partly from oil spill.