ICP-MS对超市和个体售淀粉类食品中重金属铅的测定及分析

Determination and analysis of heavy metal lead in supermarkets and individual starch foods sold by ICP-MS

目的分析和比较超市和个体摊点所售淀粉类食品中重金属铅有害元素的含量,了解超市和个体摊位所售淀粉类食品的质量状况。方法在石家庄市市区、县的个体摊点、超市和农贸市场随机选取了205份淀粉类食品,按照《2021年国家食品污染和有害因素风险监测工作手册》中方法,采用电感耦合等离子质谱(inductively coupled plasma mass spectrometry,ICP-MS)法对淀粉类食品馒头、面包、蛋糕、油条、粉丝和凉粉中的重金属铅进行分析测定。结果重金属铅元素的线性关系良好,相关系数为0.9997,加标回收率为96.0%~98.1%,相对标准偏差为3.6%。6类205份食品中重金属铅的检出率为33.2%(68/205),合格率为96.1%(197/205),其中超市售卖的102份食品中检出26份,铅的检出率为27.2%(26/102),合格率为98.1%(2/102),个体摊位售卖的103份食品中铅的检出率为40.8%(42/103),合格率为95.1%(98/103),超市售卖的食品质量高于个体售卖食品。食品中只有凉粉和蛋糕的含铅量未超标,合格率为100.0%,部分食品仍检出微量重金属元素。结论石家庄市市售淀粉类食品受到不同程度的重金属污染,为保证居民健康,应该加强监督力度,确保淀粉类食品的质量安全。

Objective Analyze and compare the content of heavy metal lead harmful elements in starchy foods sold in supermarkets and individual stalls,and understand the quality status of starch food sold in supermarkets and individual stalls.Methods A total of 205 starchy foods were randomly selected from individual stalls,supermarkets,and farmers′markets in Shijiazhuang City and county,and the heavy metal lead in starchy food steamed bread,bread,cake,fried dough sticks,fans and cold jelly was analyzed and determined by inductively coupled plasma mass spectrometry(ICP-MS)in the 2021 National Food Contamination and Harmful Factors Risk Monitoring Work Manual.Results The linear relationship of heavy metal lead was good,with a correlation coefficient of 0.9997,the spike recovery rate was 96.0%to 98.1%,and the relative standard deviation was 3.6%.The detection rate of heavy metal lead in 205 foods in 6 categories was 33.2%(68/205),and the qualified rate was 96.1%(197/205).Heavy metal lead was detected in 26 of 102 samples sold in supermarkets,with a detection rate of 27.2%(26/102)and a qualified rate of 98.1%(2/102).The detection rate of lead in foods sold by individual stalls was 40.8%(42/103),and the qualified rate was 95.1%(98/103).The quality of food sold in supermarkets was higher than that of individual stalls.Only the lead content of cold jelly and cake did not exceed the standard,and the qualified rate was 100.0%,and trace heavy metal elements were still detected in some food.Conclusion The starchy food sold in Shijiazhuang is contaminated with heavy metals to varying degrees.To ensure the health of residents supervision should strengthen supervision to ensure the quality and safety of starch foods.