食品安全风险监测中痕量汞测定质量控制的研究

Study on quality control of the determination of mercury in food safety risk monitoring

目的通过对测定食品中汞元素的实验过程质量控制,提高实验结果的准确性。方法采用不同的前处理以及测定方法对多种标准物质中的汞含量进行测定并对比,观察在不同存放条件下汞测定结果的差异。结果电感耦合等离子质谱法与原子荧光光谱法测定汞检出限(LOQ)分别为0.06μg/L与0.15μg/L;相关系数(r)均≥0.9990,相对标准偏差RSD分别为4.9%及4.1%;湿式消解、微波消解及高压罐消解处理GBW10048-芹菜结果均落在标准值的可信范围内,微波消解及高压罐消解较湿法消解有更好的精密度;电感耦合等离子质谱法测定6种国家标准物质结果均落在标准值的可信范围内,而原子荧光光谱法除了对汞含量较低的GBW10018-鸡肉及GBW10043-辽宁大米测定出现偏差外,其余结果均落在标准值可信范围内。结论通过对实验过程进行严格的质量控制及采取恰当措施,将有助于提高测定痕量汞的准确度。

Objective To improve the accuracy of experimental results by means of quality control of the determination of mercury in food.Methods A comparison was made after the determination of mercury in multiple standard substance with different pretreatment and assay methods. The difference in the storage condi-tions of determination results of mercury was also found.ResultsThe LOQs of mercury determined by ICP-MS and AFS were 0.06μg/L and 0.15μg/L, respectively. The correlation coefficients were both≥0.9990. The RSDs were 4.9% and 4.1%, respectively. The results of GBW10048 with three pretreatment methods were found to be within tolerable limits. However, the results made by microwave digestion and high pressure digestion had a better precision. The results of 6 kinds of standard substances determined by ICP-MS were all in the scope of standard values. While, the results determined by AFS were also in the scope of standard values except GBW10018 and GBW10043 with low mercury contents.Conclusion It will contribute to advance the accuracy of trace mercury determinations via strict quality control and appropriate measure.