婴幼儿谷类辅助食品中砷形态分析

Detection of arsenic species in cereal-based complementary food for infants and young children

目的建立婴幼儿谷类辅助食品中砷形态的分析方法,对市售婴幼儿谷类辅助食品中砷的形态及含量进行调查,了解婴幼儿谷类辅助食品中砷的污染现状。方法建立高效液相色谱与电感耦合等离子体质谱联用技术(HPLC-ICP-MS)测定婴幼儿谷类辅助食品中砷形态,对市售婴幼儿谷类辅助食品进行砷形态分析。结果建立的砷形态分析方法在0~100μg/L范围内具有良好的线性关系,加标回收率在83.9%~94.4%,相对标准偏差(RSD)<5%。婴幼儿谷类辅助食品中砷形态以无机砷、二甲基砷酸(DMA)为主,无机砷与总砷含量存在正相关关系(r=0.636,P<0.001),无机砷检出率为90%,调查样品未见无机砷超标。结论建立的HPLC-ICP-MS测定婴幼儿谷类辅助食品中砷形态方法快速、准确,适用于婴幼儿谷类辅助食品中砷化合物的测定。

Objective To develop a method for the determination of arsenic species in cereal-based complementary food for infants and young children （infant cereals） and to examine the form and content of arsenic in infant cereals. Methods The arsenic species in infant cereals were analyzed by establishing a method of high performance liquid chromatography and inductively coupled plasma mass spectrometry （HPLC-ICP-MS）. Results The established method for arsenic species analysis is of good linearity for the concentration range of 0 - 100.0μg/L, with a mean recovery of 83.9 % - 94.4 % and a relative standard deviation of less than 5 %. The main forms of arsenic species in the infant cereal samples detected were inorganic arsenic and dimethylarsonate. For the samples, the detection rate of inorganic arsenic is 90 % and the content of inorganic arsenic is positively correlated with that of total arsenic （r = 0.636, P 〈 0.001）. No infant cereal sample with inorganic arsenic exceeding national standard was detected. Conclusion The established HPLC-ICP-MS method is simple and accurate for the detection of arsemic species in infant cereals and could be applied in monitoring practice.