江西省稻米中总砷和无机砷含量的测定与分析

选取江西省10个县市的100份新收获稻米为实验材料,分别采用电感耦合等离子体质谱法和高效液相色谱-电感耦合等离子体质谱法,测定了稻米中的总砷和无机砷含量。测定结果表明,该方法线性方程和相关系数良好,稻米粉标准物质测定结果良好。100份稻米中的总砷含量变化为0.045~0.382mg/kg,均值为 0.170mg/kg；无机砷含量变化为0.000~0.180mg/kg,均值为 0.067mg/kg；单因素方差分析结果显示,江西省10个县市稻米中的总砷和无机砷含量之间均存在不同程度的差异性,其中无机砷含量的差异性最为显著。实验结果证实,稻米无机砷中三价As³⁺含量较高,约占无机砷含量的90%。美国环境保护署健康风险评估结果表明,江西省稻米中无机砷含量的暴露对人体健康没有风险。

Determination and Analysis on Total Arsenic and Inorganic Arsenic in Rice of Jiangxi Province

The contents of total arsenic and inorganic arsenic in 100 rice samples which were collected from 10 cities of Jiangxi were determined by inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS), respectively. The results showed that the method had good linear relationships with a correlation coefficient of more than 0.9993, and the determination of total arsenic and inorganic arsenic contents in reference material for rice flour also showed a better result. The total arsenic contents of 100 rice samples varied from 0.045 to 0.382mg/kg, with an average of 0.170mg/kg; the inorganic arsenic content varied from 0.000 to 0.180mg/kg, with an average of 0.067mg/kg. The results of SPSS analysis of variance showed that, there are significant differences in the contents of total arsenic and inorganic arsenic among various cities of Jiangxi. The results displayed that the content of As³⁺ in rice is relatively high, accounting for about 90% of inorganic arsenic content. Results of USEPA health risk assessment showed that the exposure of inorganic arsenic content in rice in Jiangxi province has no risk to human health.