多环芳烃在蔬菜体内转移、转化及降解机理的研究

With the rapid development of industry and agriculture, PAHs pollution has became more and more serious, it has been a important environmental and public health problem for every country in the world. Vegetables can absorb and accumulate the PAHs in the environment through various approaches, which threat the quality and safety of vegetables. At present, the mechanism of transfer, transformation and degradation about PAHs in vegetables are still not clear, the aspect of researches contribute to understand the influence of vegetables better for people. The project plan to further study on characteristics of vegetables absorb and accumulate the PAHs from soils and the way of transformation and degradation about PAHs in vegetables based on original researches. Meanwhile, the evaluation methodologies and standards will be discussed, which can provide theoretical references about control methods of PAHs pollution in vegetables.

随着工农业的快速发展，多环芳烃污染问题日益严峻，成为世界各国面临的重大环境与公共健康问题。蔬菜可通过多种途径吸收和积累环境中的多环芳烃，进而威胁蔬菜产品质量安全。有关多环芳烃在蔬菜体内转移、转化及降解的机理尚不清楚，开展这方面的研究有助于更好地了解多环芳烃污染对蔬菜质量安全的影响。本项目拟在原有研究基础上，进一步研究蔬菜吸收、积累土壤多环芳烃的特性及多环芳烃在蔬菜体内的转化、降解代谢途径。同时，探讨多环芳烃污染蔬菜的评价方法和标准，为防治多环芳烃污染蔬菜等农产品提供理论参考。

多环芳烃是一类具有致癌、致畸和致突变作用的持久性有机污染物，广泛分布于大气、土壤、水体中。多环芳烃能够被蔬菜吸收和富集从而通过食物链进入人体，威胁人类的健康。本项目通过研究多环芳烃在蔬菜不同器官和部位转移、积累的机理，多环芳烃进入蔬菜体内的主要途径，对蔬菜生长发育的影响及蔬菜体内的多环芳烃降解净化的措施。结果表明，菜心吸收和积累的PAHs以2～3苯环的低环类PAHs为主，低苯环类的PAHs在菜心叶片和茎中的积累量大于高苯环类的PAHs，高苯环类PAHs在根系中的积累量相对较高；PAHs胁迫使菜心VC和叶绿素含量降低，粗纤维含量增加，可溶性蛋白含量增加，使菜心相关酶活性发生上调或下调作用，进而解除PAHs胁迫；土壤施用生物质炭显著降低了低苯环类和高苯环类PAHs的生物有效性，施用微生物菌肥则显著减少了土壤中低苯环类PAHs的含量；采用不同中草药煎煮液处理，洗洁精、米酒和食用盐配置成的混合液浸泡处理，可有效降低蔬菜体内的PAHs含量。这些研究成果为防治多环芳烃污染蔬菜等农产品提供理论参考。