微波消解等离子体质谱法测定各类食品中痕量汞、镉、铅、砷准确性探讨

目的 建立微波消解-电感耦合等离子体质谱法（ICP-MS）准确测定各类食品中痕量汞、镉、铅、砷的分析方法。方法 采用微波消解法处理样品,ICP-MS测定以^72Ge、^103Rh、^185Re作为内标消除非质谱干扰,八极杆碰撞池（ORS^3）消除质谱干扰。结果 采用本方法测定汞、镉、铅、砷的定量限分别为0.05、0.05、0.40、0.40μg/L;在定量限附近测定的回收率和相对标准偏差分别为：100.0%、90.0%、96.0%、112.0%和7.6%、8.0%、11.8%、6.2%。结论 采用ICP-MS法准确测定食品中痕量有害元素的关键点及控制措施,适用于食品安全风险监测大批量样品的分析。

Accuracy in detecting trace mercury,cadmium, lead and arsenic in various kinds of food using ICP- MS assisted by microwave digestion

Objective To use microwave digestion as preferred method for sample digesting in HNO3 solution system. Methods Microwave digestion as preferred method was recommended for sample digesting. ^72Ge,^103 Rh and ^185Re were used as the internal standards to eliminate non -spectroscopic interference, and collision reaction system （ORS^3） was used to eliminate mass spectroscopic interference by ICP - MS. Results The LOQ of mercury, cadmium, lead and arsenic were 0.05,0. 05,0.4 and 0. 4μg/L, respectively. The recovery rates and value of RSD collected near the LOQ for mercury, cadmium, lead and arsenic were 100. 0% ,90. 0% ,96. 0%, 112. 0% and 7.6% ,8.0% , 11. 8% ,6. 2%, respectively. Conclusion This study shows key points and methods to determine trace mercury, cadmium, lead, and arsenic in food using ICP - MS technology. This analytical method is rapid, accurate, sensitive, and easy for operation. It is an effective method for massive sample processing in food safety risk monitoring.