PM_(2.5)对学龄儿童唾液溶菌酶含量的影响

Effect of PM_(2.5) on the content of salivary lysozyme in school-age children

目的了解PM_(2.5)对杭州市学龄儿童唾液溶菌酶含量的影响。方法按照整群随机抽样原则在杭州市下城区、西湖区、淳安县各一所小学的3~5年级班级中总共随机抽取2个班的正常健康学龄儿童作为调查对象,三校于2015年10月和2016年1月分别进行2次学生唾液溶菌酶含量检测及问卷调查。同时收集2015-2016年三校附近的环境空气质量资料,建立唾液溶菌酶含量增高的多元线性回归方程,分析PM2.5对学龄儿童唾液溶菌酶含量的影响。结果共纳入学龄儿童248名,经2次测量杭州市西湖区、下城区和淳安县儿童平均唾液溶菌酶含量分别为(566.55±157.56),(577.92±159.39)和(627.41±204.42)μg/L,三个地区儿童唾液溶菌酶含量差异有统计学意义(F=11.322,P<0.01)。西湖区和下城区PM2.5平均浓度为80μg/m^(3)和77μg/m^(3),属于高霾区,淳安县为53μg/m^(3),属于低霾区。分析显示,多元线性回归方程有统计学意义(F=6.360,P<0.01),低霾区学生唾液溶菌酶含量增高量较高霾区学生更大,开窗通风频次越少唾液溶菌酶含量增高量越大。结论PM2.5对学龄儿童唾液溶菌酶含量有影响,雾霾对学龄儿童唾液溶菌酶含量存在负效应。

Objective To investigate the effect of PM_(2.5) on the content of salivary lysozyme in school-age children in Hangzhou.Methods Healthy school-age children in two classes were selected as the objects of investigation with cluster random sampling methods from grade 3 to grade 5 of each primary school in Xiacheng District,Xihu District and Chun'an County of Hangzhou.The test of salivary lysozyme and questionnaire investigation were carried out in October 2015 and January 2016,respectively.Meanwhile,data of the environmental air quality near the three schools from 2015 to 2016 were collected.The multivariate linear regression equation of the incrementation of the salivary lysozyme content was constructed to analyze the effect of PM2.5 on salivary lysozyme content in school-age children.Results There were 248 children enrolled.The average levels of salivary lysozyme in Xihu District,Xiacheng District and Chun'an County were(566.55±157.56),(577.92±159.39)and(627.41±204.42)μg/L with significant differences(F=11.322,P<0.01).The average densities of PM2.5 in Xihu District and Xiacheng District were 80μg/m^(3) and 77μg/m^(3)(high haze area),which were higher that of Chun'an County of 53μg/m^(3)(low haze area).This multivariate linear regression equation had statistical significance(F=6.360,P<0.01).The incrementation of the salivary lysozyme content in low haze area was higher than that in high haze area.The fewer the window ventilation frequency was,the higher the incrementation of the salivary lysozyme content was.Conclusions PM2.5 influences the content of salivary lysozyme in school-age children,and haze has negative effect on it.