机动车尾气污染对学龄儿童肺功能及炎症因子水平的影响

Effect of Vehicle Exhaust Pollution on Lung Function and Inflammatory Factors Level in Pupils

目的探讨机动车尾气污染区域的健康学龄儿童污染物暴露与肺功能、炎症因子之间的关系,为研究机动车尾气暴露对学龄儿童的健康影响提供科学依据。方法选择距离交通干道约30m的某小学及符合研究条件的50名学龄儿童作为研究对象,展开时间序列专门小组研究。在靠近教学区的操场内设立一个区域监测点,于2008年5月和11月各进行连续5d的区域NOx、NO2、SO2、O3、PM2.5污染水平在线监测,并使用只读便携式仪器连续3d监测具有代表性的学龄儿童活动点(课堂教学区、课外活动区、上学路上)的NO2、SO2、O3、PM10污染水平以及对个体暴露污染后学龄儿童的健康效应进行一次测量。结果研究区域以机动车尾气污染为主。11月肺功能指标FVC%低于5月,且有统计学意义(P=0.02),NO2与FVC%呈负相关且具有统计学意义(P=0.04)。11月IL-2、IL-6、IL-8水平低于5月,而11月IL-4、TNF-α水平高于5月,个体暴露与IL-2、IL-6、IL-8呈负相关关系,其中与IL-6的相关性最强(βPM10=-0.62,βNO2=-0.62,βO3=-0.64,βSO2=-0.63),且有统计学意义(P<0.01);与IL-4、TNF-α呈正相关关系,其中在PM10与IL-4、TNF-α的关系中,与TNF-α的相关系数最强(β=0.65),而NO2、O3、SO2与IL-4、TNF-α的关系中,则与IL-4的相关系数最大(βNO2=0.69,βO3=0.74,βSO2=0.74),且均有统计学意义(P<0.01)。结论健康学龄儿童肺功能的降低与机动车尾气污染暴露有关,外周血炎症因子IL-4、IL-6、TNF-α改变与机动车尾气污染关系明显。

Objective To explore whether pollutants exposure has a measurable impact on lung function and inflammatory factors level of healthy pupils in vehicle exhaust polluted region. Methods Primary school near the trunk road with a distance no more than 30 meters was selected, and 50 qualified pupils were chosen. A time-series panel study was conducted with these pupils, and the following consecutive five days＇ study of vehicle exhaust pollution level, 3-days＇personal exposure measurement and its health effects were carried out in May and November in 2008. Results The main pollutant in this region was motor vehicle exhaust. Compared to May, the value of FVC% declined significantly in November （P=0.02）. And the reduction of the value of FVC% was negatively associated with an increase in NO2 concentrations （P=0.04）. The levels of IL-2, IL-6, IL-8 became lower in November compared with May, and were negatively associated with personal exposure with IL-6 with statistically significant difference （βPM10=-0.62, βNO2=-0.62, βO3=-0.64,βSO2=-0.63）. The levels of TNF-α and IL-4 were positively associated with personal exposure, in which PM10 has the largest regression coefficient with TNF-α（8=0.65,P〈0.01）, NO2（βNo2=0.69,P〈0.01）, O3 （βO3=0.74,P〈0.01）and SO2 （βSO2=0.74,P〈0.01）has the largest regression coefficient with IL-4. Conclusion Motor vehicle exhaust exposure may decrease the lung function and affect inflammatory cytokines （IL-4, IL-6 and TNF-α） in peripheral blood in healthy pupils.