School of Civil Engineering and Surveying, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia.
Centre for Crop Health, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, 4350, Australia; National Institute of Fundamental Studies, Hantana Road, Kandy, 20000, Sri Lanka.
Environ Int. 2019 Jun;127:584-591. doi: 10.1016/j.envint.2019.04.004. Epub 2019 Apr 12.
Human exposure to arsenic (As) through the consumption of rice (Oryza sativa L.) is a worldwide health concern. In this paper, we evaluated the major causes for high inorganic As levels in cooked rice foods, and the potential of post-harvesting and cooking options for decreasing inorganic As content in cooked rice, focusing particularly on As endemic areas. The key factors for high As concentration in cooked rice in As endemic areas are: (1) rice cultivation on As-contaminated paddy soils; (2) use of raw rice grains which exceed 200 μg kg of inorganic As to cook rice; and (3) use of As-contaminated water for cooking rice. In vitro and in vivo methods can provide useful information regarding the bioaccessibility of As in the gastrointestinal tract. Urinary levels of As can also be used as a valid measure of As exposure in humans. Polishing of raw rice grains has been found to be a method to decrease total As content in cooked rice. Sequential washing of raw rice grains and use of an excess volume of water for cooking also decrease As content in cooked rice. The major concern with those methods (i.e. polishing of raw rice, sequential washing of raw rice, and use of excess volume of water for cooking rice) is the decreased nutrient content in the cooked rice. Cooking rice in percolating water has recently gained significant attention as a way to decrease As content in cooked rice. Introducing and promoting rainwater harvesting systems in As endemic areas may be a sustainable way of reducing the use of As-contaminated water for cooking purposes. In conclusion, post-harvesting methods and changes in cooking practices could reduce As content in cooked rice to a greater extent. Research gaps and directions for future studies in relation to different post-harvesting and cooking practices, and rainwater harvesting systems are also discussed in this review.
人体通过食用大米（Oryza sativa L.）摄入砷（As）是一个全球性的健康问题。本文评估了导致米饭中无机 As 含量高的主要原因，以及收获后和烹饪过程中降低米饭中无机 As 含量的潜在方法，特别是在砷流行地区。砷流行地区米饭中无机 As 浓度高的主要原因有：（1）在受 As 污染的稻田中种植水稻；（2）使用超过 200μg/kg 无机 As 的糙米煮饭；（3）用受 As 污染的水做饭。体外和体内方法可以提供有关胃肠道中 As 生物可利用性的有用信息。尿液中 As 水平也可作为人体 As 暴露的有效衡量指标。糙米的抛光被发现是降低米饭中总 As 含量的一种方法。糙米的反复清洗和煮饭时使用过量的水也可降低米饭中 As 的含量。这些方法的主要问题（即糙米的抛光、糙米的反复清洗以及煮饭时使用过量的水）是降低了煮熟的米饭中的营养成分。用渗滤水煮饭最近受到了广泛关注，因为它可以降低米饭中的 As 含量。在砷流行地区引入和推广雨水收集系统可能是减少用于煮饭的受污染水的一种可持续方法。总之，收获后方法和烹饪习惯的改变可以在更大程度上降低米饭中的 As 含量。本文还讨论了与不同收获后和烹饪实践以及雨水收集系统相关的研究空白和未来研究方向。
