Wang Y-C, Qiao M, Liu Y-X, Arp H P H, Zhu Y-G
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.
J Environ Monit. 2011 Feb;13(2):433-9. doi: 10.1039/c0em00098a. Epub 2010 Dec 15.
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.
大气沉降是城郊地区种植蔬菜吸收多环芳烃的主要途径。在中国京津冀城市群收集的蔬菜样本中，研究了不同的多环芳烃（PAH）吸收途径及相关健康风险，该地区使用污水或再生水灌溉已有数十年。采样涵盖23个不同地点以及六种蔬菜的根和地上部分。在不同的可食用蔬菜部位中，萝卜根中的多环芳烃浓度最高，花椰菜头中的浓度最低。单个多环芳烃的生物富集系数（BCF）随log K(OW)的增加呈微弱下降趋势。为了研究空气-叶片吸收还是土壤-根-地上部分吸收占主导，将测量值与通用单室模型的估计值进行了比较。结果及相关观察结果表明，与土壤吸收途径相比，大气吸收途径更为符合。多环芳烃异构体比例与热解源（来自化石燃料和生物质燃烧）一致。对蔬菜可食用部分消费的健康风险评估表明，除16%的白菜样本外，所有研究的蔬菜食用都是安全的。本研究结果表明了食用该城市群污水灌溉区蔬菜的潜在健康风险，并为该地区种植蔬菜中多环芳烃的转移提供了新见解。
