福建省宁化县稻米镉含量调查及健康风险评估

黄锐敏 欧阳辉 吴俊 刘兰英 傅建炜

摘 要：2018年在福建省三明市宁化县所辖16个乡镇共采集水稻样品120份，对稻米样品中的镉污染状况进行调查;结合我国居民大米消费量数据，采用基于Monte-Carlo模拟的概率模型法，对宁化县范围内水稻中镉的膳食暴露风险进行评估。结果表明：宁化县水稻镉含量均值为0.0685 mg·kg-1，稻米样品总体镉污染程度很轻;参考美国环境保护署的化学污染物健康风险评估模型进行评估，结果表明不同消费人群对稻谷Cd的暴露水平总体呈现低龄高于高龄的特点，稻谷Cd暴露水平相对较高的是11岁以下人群（2～11岁）;消费人群食用宁化县种植水稻引起的镉暴露水平较低，风险较小。

关键词：水稻;镉;重金属污染;膳食暴露;风险评估

中图分类号：S511 文献标志码：A 文章编号：0253-2301（2020）05-0030-07

Abstract： In 2018， 120 rice samples were collected from 16 townships under the jurisdiction of Ninghua County in Sanming City of Fujian Province， in order to to investigate the cadmium pollution in the rice samples. Based on the data of rice consumption in China， the probability model based on Monte Carlo simulation was used to evaluate the dietary exposure risk of cadmium in rice in Ninghua County. The results showed that the average cadmium content of rice in Ninghua County was 0.0685 mg·kg-1， and the cadmium pollution degree of the rice samples was very light. Based on the health risk assessment model of chemical pollutants from the United States Environmental Protection Agency， the assessment was carried out， and the results showed that the exposure level of cadmium in rice of different consumer groups was generally characterized by the fact that the younger age group was higher than the older age group， and the relatively high exposure level of cadmium in rice existed in the group under the age of 11（2-11 years old）. The level of cadmium exposure caused by the rice grown in Ninghua County was low and the risk was small.

Key words： Rice; Cadmium; Heavy metal pollution; Dietary exposure; Risk assessment

隨着经济的迅速发展，相对应而来的重金属污染也随之普遍[1]。重金属一般是指密度大于4.5 g·cm-3的金属，不能被土壤中的微生物所分解，因而会在土壤中不断积累，影响土壤性质[2]。镉是生物体非必须且毒害性极强的重金属元素，在生态系统中具有极强的迁移能力，在人类活动影响下，随着金属冶炼、电镀工业、废弃物处置、肥料施用、化石燃料燃烧、大气沉降等过程进入水体和土壤中[3-5]。土壤中的镉经过植物吸收、积累，通过作物可食部进入食物链进而直接或间接地积累在人体中，危害人体健康[6-7]。

镉进入水稻体内后，影响线粒体及叶绿体的功能[8-9]，抑制叶肉细胞的生长，降低叶中叶绿素的含量，最终导致叶片光合作用率下降[10-11]。……