北京市部分超市销售食品的铅含量分析

目的:研究北京市部分超市销售食品的铅含量,为北京市食品安全评估提供参考依据。方法:采集北京市近40家超市销售的28类(总计496件)样品,采用石墨炉原子吸收光谱法(GF-AAS)对样品铅含量进行测定,方法检出限为0.005 mg·kg^-1,在质量浓度0~20 μg·L^-1范围内线性相关系数介于0.9989~0.9995。结果:28类样品铅含量平均值为0.0957 mg·kg^-1,95%置信区间为0.0191~0.2104 mg·kg^-1。结论:组间聚类分析表明,香辛料和液态调味料(Ⅰ类,含量范围为0~2.8944 mg·kg^-1)、半固态调味品和方便面食(Ⅱ类,含量范围为0~0.3328 mg·kg^-1)、小麦粉、白酒和蔬菜等24类样品(Ⅲ类,含量范围为0~0.0983 mg·kg^-1)铅含量依次降低。

Analysis of lead concentrations of foods in some supermarkets in Beijing

Objective:To analyze concentrations of lead in foods sold in some supermarkets in Beijing and to provide reference for local food safety assessment. Methods:496 food samples of 28 types were collected from nearly 40 supermarkets. Concentrations of lead was determined by using graphite furnace atomic absorption spectrometry(GF-AAS),the detection limit was 0.005 mg·kg-1,and linear correlation coefficient was between 0.9989~0.9995 when mass concentration stay within 0~20 μg·L-1. Results:The average concentration of lead of those samples was 0.0957 mg·kg-1,and 95% confidence interval was 0.0191~0.2104 mg·kg-1. Conclusion:Hierarchical cluster analysis showed that concentrations of lead decreased in the following order:spices and liquid seasoning(class Ⅰ),semisolid condiments and instant noodles(class Ⅱ),and other 24 kinds of samples including wheat flour,white wine and vegetables(class Ⅲ). Lead concentrations of the above three classes were 0~2.8944,0~0.3328,0~0.0983 mg·kg-1,respectively.