天津市学龄儿童尿铅与智商、学习成绩及在校行为关系的研究

Study on the Relationships Between Urine Lead and Intelligence Quotient, Academic Achievement and Behavior in School-age Children

目的探讨环境铅暴露条件下儿童的尿铅水平及其对智商、学习成绩及在校行为的影响。方法对天津市区和郊区7～12岁学龄儿童尿铅、智商 (IQ )进行测定 ;对学习成绩、在校行为进行调查 ;对尿铅与智商、学习成绩及在校行为的关系进行分析。结果118名学龄儿童尿铅水平为 (7.04±3.53) μg/L ,其中市区组和郊区组儿童尿铅分别为(7.71±3.52) μg/L和 (6.37±3.45) μg/L ,两组差异显著 (P<0.05) ;市、郊两组儿童的IQ差异无显著性 (P>0.05) ;IQ<80组的儿童尿铅水平显著高于IQ≥80组[两组尿铅分别为 (10.31±2.16) μg/L和 (6.89±3.52) μg/L ,P<0.05)] ,并且 ,较高尿铅 (≥7μg/L)组儿童的学习成绩、在校行为的得分均显著低于尿铅组 (P均<0.05) ;多元逐步分析结果表明 :尿铅对IQ的影响无显著性 ,但尿铅是显著影响学习成绩及在校行为的因素之一。结论天津市区儿童尿铅水平显著高于郊区 ;

Objective To determine the urine lead level in school_age children under conditions of environmental lead exposure and evaluate the effects of the presence of body lead on IQ, academic achievement and behavior in school of these children. Methods The concentrations of urine lead and IQs for 118 children aged 7～12 were measured. The academic achievement, behavior in school and the correlated factors were derived from the questionnaires given to their teachers and parents. Results The urine lead level of 118 children was (7.04±3.53)μg/L. In children who lived in city central area the urine lead level was (7.71±3.52)μg/L. It was significantly higher than that of children who lived in a suburban area [(6.37±3.45)μg/L]; No significant differences were observed in IQ between children in city and suburbs. The results by single factor analysis showed that the urine lead level [(10.31±2.16)μg/L] in the lower IQ group (IQ<80) was significantly higher than that [(6.89±3.52)μg/L] of the normal IQ group (P<0.05). The scores of academic achievement and behavior in the higher urine lead (≥7 μg/L) group were significantly lower than that of the lower urine lead group (P<0.05); By multiple factor step_wise regression analysis, no significant relation between urine lead level and IQ was demonstrated while significant relations were shown between urine lead level and academic achievement and behavior. Conclusions The urine lead level in children who lived in the Tianjin city central area was significantly higher than that of children who lived in the suburban area. Even low urine lead level in children might have some adverse effects on the central nervous system.