稻米镉积累的影响因素与阻控措施

A review on drivers and mitigation strategies for elevated cadmium concentration in rice

长期高镉暴露能引发"痛痛病"等疾病,镉的人体健康危害不容小视.目前我国镉污染较为严重,因其容易富集于水稻等粮食作物而备受当前环境、食品领域的关注.镉污染大米(也称为"镉米")摄入是目前人体镉暴露的最重要来源,探究"镉米"的形成及影响因素,并针对影响因素提出相应的阻控措施对保障食品安全和人体健康具有重要意义.本文针对土壤—水稻体系,简介了当前我国稻田镉污染现状,分析了土壤理化性质、全球变暖、水稻品种、水稻根系结构、水稻根系基因对水稻镉吸收的影响,总结了镉被吸收后在水稻植株内的分布和迁移过程及相关调控基因,探讨了土壤修复、基因调控、稻米加工、膳食摄入等措施降低大米镉含量及人体健康风险的效果.本文揭示了稻米镉积累的关键影响因素,并对今后"镉米"阻控措施的发展方向进行了展望.

Long-term exposure to cadmium(Cd) can cause Itai-Itai disease and other diseases, therefore the associated health risks cannot be ignored. Currently, environmental Cd contamination is quite serious in China. Cadmium is easy to be taken up and accumulated in rice and other food crops, so Cd contamination in the environment is raising increasing concern. It is well accepted that intake of Cd-contaminated rice(also known as "Cd rice") is the most major source of Cd exposure for humans. Thus, to ensure food safety and human health, it is important to explore factors influencing Cd accumulation in rice and to develop mitigation strategies to decrease Cd concentration in rice. This review introduces the status of Cd contamination in Chinese rice paddy fields, analyzes effects of soil physical and chemical properties, global warming, rice varieties, rice root structure, and rice root genes on Cd uptake by rice, and discusses Cd distribution and transportation in rice plants following uptake and the related regulatory genes. In addition, mitigation strategies including soil remediation, rice gene regulation, rice processing, and dietary intake to reduce rice Cd concentration and human health risks are discussed. This review reveals key factors controlling rice Cd accumulation and prospects the future research directions for developing mitigation strategies.