title: Comparison of polycyclic aromatic hydrocarbon uptake pathways and risk assessment of vegetables from waste-water irrigated areas in northern China.
abstract: Atmospheric deposition is the dominant pathway for PAH uptake by vegetables grown in peri-urban areas. Different polycyclic aromatic hydrocarbon (PAH) uptake pathways and the associated health risk were investigated in vegetable samples collected from the Beijing-Tianjin city cluster, China, where irrigation with waste or reclaimed water has been practised for many decades. Sampling comprised 23 diverse sites and the roots and shoots of six types of vegetables. Among the different edible vegetable parts, the highest PAH concentrations were found in radish roots and the lowest in cauliflower heads. Bioconcentration factors (BCFs) for individual PAHs showed a weakly decreasing trend with increasing log K(OW). To investigate whether the air-leaf or soil-root-shoot uptake dominates, the measured values were compared with estimations from a generic one-compartment model. The results and related observations are more consistent with an atmospheric uptake pathway than a soil-uptake pathway. The PAH isomeric ratios are consistent with pyrogenic sources (from combustion of fossil fuel and biomass). A health risk assessment on the consumption of the edible parts of vegetables revealed that all studied vegetables, except for 16% of Chinese cabbage samples, are safe for consumption. The results of this study indicate the potential health risk of consuming vegetables from waste-water irrigated areas of this city cluster and provide new insights regarding the transfer of PAHs in vegetables grown in this region.
authors.affiliation: State Key Lab of Regional and Urban Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Shuangqing Road 18, Haidian District, Beijing 100085, PR China.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Qiao
authors.forename: Y-X
authors.initials: YX
authors.lastname: Liu
authors.forename: H P H
authors.initials: HP
authors.lastname: Arp
authors.forename: Y-G
authors.initials: YG
authors.lastname: Zhu
mesh_terms: D002681:China; D002947:Cities; D004784:Environmental Monitoring; D005506:Food Contamination / Q000032:analysis*; D008954:Models, Biological; D010539:Permeability; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000378:metabolism; D018570:Risk Assessment; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism; D014675:Vegetables / Q000378:metabolism*; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical