北京市蔬菜重金属含量及健康风险评价

Concentrations and health risk evaluation of heavy metals in vegetables in Beijing

目的研究北京市本地产蔬菜和市售外地产蔬菜中重金属污染情况,评价经蔬菜膳食途径摄入重金属的人体健康风险。方法采用原子吸收光谱法和原子荧光光谱法测定4种蔬菜样品中Pb、Cd、Cr、As、Hg含量,并与中国食品中污染物限量标准进行比较;采用美国环保署(USEPA)(2000)提出的健康风险模型,通过计算目标危害系数(THQ、TTHQ)的方法预测蔬菜中重金属产生的健康风险。结果 327份蔬菜样品中的5种重金属均不超标;从单一重金属风险来看,成人和儿童膳食摄入所调查的4种北京市本地产蔬菜和市售外地产蔬菜是安全的;从多种重金属复合风险来看,部分北京市本地产韭菜对儿童存在一定的膳食摄入风险,4种市售外地产蔬菜对成人和儿童不存在健康风险;成人和儿童的复合健康风险主要由As引起。结论在所调查的5种重金属中,部分韭菜中的As经膳食途径摄入后会对儿童健康构成潜在威胁,儿童因摄食蔬菜导致的重金属健康风险高于成人。

Objective To study the heavy metals content characteristics and examine the human health risk of heavy metal in vegetables produced in Beijing and that sold in Beijing markets produced from other provinces.Methods The atomic absorption spectrometer (AAS) and atomic fluorescence spectrometer(AFS) were adopted to detect heavy metal content of total lead (Pb), total cadmium (Cd), total chromium (Cr), total arsenic (As) and total mercury (Hg) in 4 kinds of vegetable samples. Those of results were compared with main vegetable standards of China. Under the healthy risk model proposed by USEPA (2000), the health risks of heavy metals were forecasted by the method of calculating the risk index (the target hazard quotient, THQ and TTHQ).Results Concentrations of the 5 heavy metals in all vegetables were all below the maximum allowable limits; for adults and children, 4 kinds of vegetables produced in Beijing and those sold in Beijing markets produced from other provinces were safe by analyzing THQ of single heavy metal; for children, some Chinese chive samples produced in Beijing were danger by analyzing TTHQ of multiple heavy metal; for adults, 4 kinds of vegetables produced in Beijing and those sold in Beijing markets produced from other provinces were safe by analyzing TTHQ of multiple heavy metal; overall health risks were mainly caused by As. Conclusion With 5 kinds of investigated heavy metals, some As levels in Chinese chive posed a health risk to children, health risks to consume vegetables caused by heavy metals for children were bigger than adults.