title: A passive air sampler for characterizing the vertical concentration profile of gaseous phase polycyclic aromatic hydrocarbons in near soil surface air.
abstract: Air-soil exchange is an important process governing the fate of polycyclic aromatic hydrocarbons (PAHs). A novel passive air sampler was designed and tested for measuring the vertical concentration profile of 4 low molecular weight PAHs in gaseous phase (PAH(LMW4)) in near soil surface air. Air at various heights from 5 to 520 mm above the ground was sampled by polyurethane foam disks held in down-faced cartridges. The samplers were tested at three sites: A: an extremely contaminated site, B: a site near A, and C: a background site on a university campus. Vertical concentration gradients were revealed for PAH(LMW4) within a thin layer close to soil surface at the three sites. PAH concentrations either decreased (Site A) or increased (Sites B and C) with height, suggesting either deposition to or evaporation from soils. The sampler is a useful tool for investigating air-soil exchange of gaseous phase semi-volatile organic chemicals.
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Yuzhong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Shuxing
authors.initials: S
authors.lastname: Deng
authors.forename: Yanan
authors.initials: Y
authors.lastname: Liu
authors.forename: Guofeng
authors.initials: G
authors.lastname: Shen
authors.forename: Xiqing
authors.initials: X
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Cao
authors.forename: Xilong
authors.initials: X
authors.lastname: Wang
authors.forename: Brian
authors.initials: B
authors.lastname: Reid
authors.forename: Shu
authors.initials: S
authors.lastname: Tao
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002138:Calibration; D002681:China; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D005740:Gases / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D011140:Polyurethanes; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D005740:Gases; D011084:Polycyclic Aromatic Hydrocarbons; D011140:Polyurethanes; D012989:Soil Pollutants