分别采用电感耦合等离子体质谱测定大米中总砷含量和高效液相色谱与电感耦合等离子体质谱联用测定大米中不同形态无机砷的含量,并研究了2种方法测定总砷和无机砷的条件。结果表明:大米中砷的存在形式有As(Ⅲ)、As(Ⅴ)、二甲基砷及一种未知的砷化合物;测定样品中As(Ⅲ)、As(Ⅴ)含量分别为3.4μg/kg和17.4μg/kg,其加标回收率为90%-106%,相对标准偏差为3.52%。而样品中总砷含量为88.13μg/kg,其加标回收率在94%-103%,相对标准偏差为1.29%。

The determination of total arsenic in rice was analyzed by inductively coupled plasma mass spectrometry,the inorganic arsenic was detected by coupling high-pressure liquid chromatography with inductively coupled plasma mass spectrometry.The results showed that the rice contained DMA,As(Ⅲ),、As(Ⅴ) and an unknown arsenic compound.The contents of As(Ⅲ) and As(Ⅴ) were 3.4 μg/kg and 17.4 μg/kg,respectively,and recoveries for samples were in the range of 90%-106%,and the value of RSD was 3.52%.The total arsenic was 88.13 μg/kg.Recoveries for samples were in the range of 94%-103%,and the value of RSD was 1.29%.