市售谷物中 Pb 和 Cd 含量测定与风险评估

摘要

The Pb and Cd contents in 12 kinds of cereal samples were determined by microwave digestion-graphite furnace atomic absorption spectrometry,respectively.The pollution situations of the samples were assessed according to the national safety standards about the pollutant in cereal.The dietary expo-sure risk of Pb and Cd in cereal was assessed according to the maximum allowable intake of heavy metal pollutants (RfD value)recommended by USEPA (2000).The results showed that the exposure risk coef-ficient of Pb and Cd was less than 1 with the dietary patterns of eating single rice or two kinds of grain collocation.But all samples were slightly contaminated by Pb;maize,oat and wheat flour were slightly contaminated by Cd;while rice,pea,broad bean were around the warning line of Cd pollution.It is nec-essary to reinforce supervision of heavy metal pollution in agricultural products market.%采用微波消解—石墨炉原子吸收光谱法测定市售12种谷物（豆类）中的 Pb、Cd 含量，按照我国粮食污染物限量安全标准分析其污染水平，依据美国环境保护局推荐的重金属污染物最大允许摄入量（RfD 值）评估谷物中 Pb、Cd 污染的膳食暴露风险。结果显示，以单一大米及大米、小麦粉和其他谷物搭配的两种谷物膳食模式的 Pb、Cd 污染暴露风险指数均＜1，不存在健康安全暴露风险；但12种谷物样品均存在轻度 Pb 污染风险，玉米、燕麦、小麦粉等样品存在轻度 Cd 污染风险，大米、豌豆和蚕豆等样品处于 Cd 污染警戒线，应加强对农产品销售市场重金属污染安全风险的监测。