Selection of rice cultivars having low-grain cadmium in cadmium-polluted paddy fields in Thailand

从泰国Tak省Mae Sot区Pha Te村的所有23户家庭收集了家庭消费的稻米。这个地区被一个锌矿的镉污染了。脱壳米（Oryza sativa L.）籽粒中Cd含量在0.04 ~ 1.75mg Cd kg-1之间，超过半数家庭的大米Cd含量高于CODEX标准精米0.4 mg Cd kg-1的临界值。为了降低村民的健康风险，我们开始选择籽粒Cd低于流行品种Khao Dawk Mali (KDM) 105的水稻品种。在42个泰国水稻品种（Oryza sativa L.）中，RD5、RD15和Sang Yod的籽粒Cd积累水平低于KDM105。研究结果表明，选择低镉水稻品种可以减少人体镉的摄入量，并于2013年5月通过当地一个非政府组织向村民宣布了这一令人鼓舞的结果。

Home-consumed rice grains were collected from all 23 households in the village of Pha Te, Mae Sot District of Tak Province, Thailand. This area has been polluted with Cd from a zinc mine. The Cd concentration in unhusked rice (Oryza sativa L.) grains ranged from 0.04 to 1.75mg Cd kg-1, and the rice of more than half of the households contained Cd levels higher than the critical level of 0.4 mg Cd kg-1 polished rice, which is the CODEX standard. To reduce the health risk of the villagers, we started to select rice cultivars having lower grain Cd than that of a prevailing cultivar Khao Dawk Mali (KDM) 105. Among 42 cultivars of Thai rice (Oryza sativa L.), lower levels of Cd accumulated in the grains of RD5, RD15, and Sang Yod than KDM105. The findings suggest that human cadmium intake can be reduced by selecting low-Cd rice cultivars, and the promising result was announced to the villagers at May 2013 through a local NGO group.