近日，环境科学类主流刊物Environmental Science & Technology以新闻的形式公布了中国科学院生态环境研究中心研究员朱永官及其合作者的最新研究成果，该项研究通过野外调查和模拟试验证实：在砷污染条件下，水稻籽粒中硒和锌的含量明显降低。
据介绍，砷是一个强致癌物质，该小组前期的研究已经表明对于以大米为主食的人群来讲，水稻砷污染是人体暴露砷的重要途径。而硒和锌作为人体抗氧化系统的必须微量元素，在降低砷污染的健康效应具有潜在的作用。令人遗憾的是，砷污染似乎是一个雪上加霜的问题，因为砷在水稻体内的积累不仅直接影响人体健康，还可以通过降低一些人体必须的微量元素含量给人体健康带来间接的影响。不过情况并不是都很糟，朱永官研究员参与的另一项研究发现：通过培育低砷水稻品种，人类有可能有效降低砷污染带来的健康风险。但是，该成果表明：由于基因与环境的互作，人们又必要针对不同的土壤和气候特征培育不同的水稻品种，以满足不同地区应对砷污染的需要。Environmental Science & Technology网站也进行在线发表。（生物谷Bioon.com）
生物谷推荐原始出处：
Environ. Sci. Technol., 2009, 43 (10), pp 3556–3560 DOI: 10.1021/es803368y
Uptake and Acropetal Translocation of Polycyclic Aromatic Hydrocarbons by Wheat (Triticum aestivum L.) Grown in Field-Contaminated Soil
Yuqiang Tao, Shuzhen Zhang*, Yong-guan Zhu and Peter Christie
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China, and Agri-Environment Branch, Agriculture Food and Environmental Science Division, Agri-Food and Biosciences Institute, Queen’s University of Belfast, Newforge Lane, Belfast BT9 5PX, U.K.
Uptake and acropetal translocation of 14 priority polycyclic aromatic hydrocarbons (PAHs) by wheat (Triticum aestivum L.) grown in 15 field-contaminated soils were investigated in a growth chamber. PAH concentrations in roots correlated positively with the corresponding concentrations in soils and negatively with the contents of soil organic carbon (p < 0.01). No clear linear relationship was found between log RCF (root concentration factor, μg g?1root/μg g?1soil on dry weight basis) and log Kow of these PAHs. Four-ring PAHs had the highest tendency to be taken up by roots. PAH concentrations in shoots correlated well with their concentrations in soils and roots. Furthermore, distribution profiles of PAHs in shoots were fairly similar to those in soils. Acropetal translocation of 10 PAHs (with log Kow varying from 3.45 to 5.78) was also implicated by Rt (ratio of PAH from root-to-shoot translocation to the total accumulation in shoots) ranging from 53.6 to 72.6%. A negative linear relationship was found between log Rt and log Kow of these PAHs (p < 0.01), and acropetal translocation of PAHs depended on their chemical properties.
