食品包装材料中重金属的质谱测定及来源分析

Determination of Heavy Metal Elements in Food Packaging Materials by Inductively Coupled Plasma Mass Spectrometry and Analysis of Their Sources

利用电感耦合等离子体质谱法(ICP-MS)对市售纸质食品包装材料中的7种重金属元素进行分析测定,并探讨其来源。样品经密闭高压消解处理后,以氦气(4He)作为碰撞反应气,铋(209Bi)、钪(45Sc)、铟(115In)、锗(74Ge)作为内标,采用ICP-MS测定样品中砷(75As)、锑(121Sb)、镉(111Cd)、铅(208Pb)、铬(52Cr)、镍(60Ni)和汞(202Hg) 7种元素含量。75As、121Sb、111Cd、208Pb、52Cr和60Ni分别在0.1~50.0μg/L范围内、202Hg在0.05~10.0μg/L范围内均呈良好的线性关系, 7种元素标准曲线的相关系数均大于0.999,检出限分别为0.005, 0.001, 0.001, 0.03, 0.05, 0.008和0.001mg/kg,样品加标回收率在95.0%~110%之间,相对标准偏差(RSD)均小于4%,精密度良好,选用国家有证标准物质圆白菜(GBW 10014)验证方法的准确度,测定值均在标准物质标示值范围内。试验方法适用于纸质食品包装材料中75As、121Sb、111Cd、208Pb、52Cr、60Ni和202Hg的批量快速检测。

The content of seven heavy metal elements(As,Sb,Cd,Pb,Cr,Ni and Hg)in food packaging materials was determined by inductively coupled plasma mass spectrometry(ICP-MS)and their origins were discussed.Samples were digested by sealed high pressure digestion and 4He was used as collision to eliminate mass spectroscopic interference.The209Bi,45 Sc,115In and 74Ge were employed as internal standards to eliminate the interference of the matrix,and the content of seven elements in food packaging materials was determined by ICP-MS.The As,Sb,Cd,Pb,Cr,Ni showed a good linear relationship in the range of 0.1-50.0μg/L and Hg showed a good linear relationship in the range of 0.05-10.0μg/L.The correlation coefficients of the standard curves were greater than 0.999.The detection limits were 0.005,0.001,0.001,0.03,0.05,0.008 and 0.001 mg/kg,respectively.The recovery rate of 75As,121Sb,111Cd,208Pb,52Cr,60Ni and 202Hg were 95%-110%and the relative standard deviation(RSD)was less than 4%.National certified reference materials of cabbage(GBW 10014)were selected to validate the method and the analytical results obtained were in good agreement with the recommended values.The results showed that inductively coupled plasma mass spectrometry was suitable for the quick determination of 75As,121Sb,111Cd,208Pb,52Cr,60Ni and 202Hg in food packaging materials.