上海市浦东新区中小学生膳食铅暴露水平

Dietary exposure of lead in primary,middle and high school students in Pudong new area of Shanghai

目的了解上海市浦东新区中小学生膳食中铅的暴露水平,为针对目标人群开展食品安全风险评估和管理提供依据。方法采用多阶段分层随机抽样方法抽取上海市浦东新区616名中小学生,采用称重法、3 d 24 h膳食回顾和食物频率法相结合的方法进行食物消费量调查,检测采集的1 145件食品样本中铅的含量,计算中小学生的铅暴露水平。结果有568件食品样本检出铅,总检出率为49.61%;41件铅超标,总超标率为3.58%。铅平均含量为(0.12±0.25)mg/kg,铅含量前3位的食品类别依次为菌藻类、豆类及其制品和水产类及其制品。中小学生每周膳食铅暴露量均值为9.94μg/kg,占暂定每周可耐受摄入量(provisional tolerated weekly intake,PTWI)的39.76%,其中膳食高消费学生的每周膳食铅暴露量为29.56μg/kg,占PTWI的118.24%。蔬菜类及其制品、豆类及其制品和谷类及其制品是学生膳食铅摄入的主要来源,其每周膳食铅暴露量均值分别为2.57,2.44和1.43μg/kg,占PTWI的百分比分别为10.26%,9.76%和5.74%。结论上海市浦东新区市售食品中存在一定程度的铅污染,中小学生膳食中铅暴露的总体风险处于可接受水平,但不同食物消费量人群铅暴露水平有一定差异,应引起重视。

Objective To obtain the dietary exposure of lead in primary,middle and high school students,and to provide basic foundation for food safety risk assessment and management for children and adolecsents. Methods Weighing method,3-days hour dietary survey,combining with the food frequency questionnaire,was applied to obtain basic dietary data in 616 primary,middle and high school students selected through multi-stage randdom sampling method from Pudong new area of shanghai. Data on lead concentrations were derived from the food safety risk monitoring system,which included 1 145 samples. Results Lead was detected in 568 of 1 145 samples( 49.61%) from 10 categories of foods. The exceeding standard rate was 3.58%( 41 samples exceeded). The average content of lead was( 0.12±0.25) mg/kg,fungi and algae,beans and the aquatic products were found to be the primary food sources of lead exposure. The average dietary lead exposure in primary,middle and high school students was 9.94 μg/kg per week,accounted for 39.76% of PTWI. The lead exposure level at the 97. 5 th percentile which accounted for 118. 24% of PTWI was 29.56 μg/kg. Vegetables,beans and cereal foods were the mainly source of dietary lead exposure,with average dietary lead exposure 2.57,2.44 and 1.43 μg/kg peer week,accounted for 10.26%,9.76% and 5.74% of PTWI,respectively. Conclusion Lead is present in some foods available in local markets in Pudong New Area,Shanghai. Low level of dietary exposure to lead is found in primary,middle and high school students,however,it depends on dietary pattern. Continued efforts are needed to reduce the dietary exposure of lead in school students.