天津儿童冬季PM2.5室内暴露与个体暴露特征及来源

2011年11─12月使用颗粒物个体采样泵对天津42名儿童(9~12岁)的PM_2.5暴露进行了研究,分别采集了冬季儿童PM_2.5个体暴露和家庭室内暴露的滤膜样品. 使用ICP-MS/OES方法分析了室内暴露和个体暴露PM_2.5载荷的元素. 结果表明:天津儿童冬季PM_2.5个体暴露浓度(以ρ计)平均值为(129.3±66.6)μg/m3,室内暴露浓度平均值为(114.0±61.7)μg/m3. 个体暴露和室内暴露各元素质量浓度之和分别占ρ(PM_2.5)的19.4%和17.1%. 相关分析指出,PM_2.5室内暴露浓度和个体暴露浓度在0.01水平上显著相关. 回归分析表明,大多数元素的个体暴露浓度与室内暴露浓度呈正相关. 由EF(富集因子)分析可知,Zn、Pb、Cu、Cr、Ni、Sn、As、Sb、Cd、Tl、Bi、W、Mo在个体暴露和室内暴露样品中明显富集. 由主成分分析可知,天津儿童冬季PM_2.5室内暴露来源可能为燃煤和机动车尾气的混合源、燃油飞灰、土壤尘、建筑尘；而个体暴露来源除上述人为源外,还包括工业尘. 

Characteristics and Sources of Elements of PM2.5 for Indoor and Personal Exposure of Children during Winter in Tianjin

To investigate children's personal and indoor exposure to PM_2.5, an intensive field study of monitoring was conducted from November to December in 2011 in Tianjin. The results showed that mass concentrations of personal and indoor exposures of children to PM_2.5 were (129.3±66.6)μg/m3 and (114.0±61.7)μg/m3, respectively. The total mass concentrations of elements accounted for 19.4% and 17.1% of the total mass concentrations for personal and indoor PM_2.5, respectively. Linear regression analysis indicated that most of the elements in PM_2.5 of personal exposure positively correlated with those of indoor exposure. Spearman analysis showed that the mass concentration of PM_2.5 of personal exposure significantly correlated with the mass concentration of indoor PM_2.5. Enrichment factor (EF) analysis indicated high values of EF for Zn, Pb, Cu, Cr, Ni, Sn, As, Sb, Cd, Tl, Bi, W and Mo, showing that these elements were affected by anthropogenic sources. Principal component analysis showed that the sources of personal exposure to PM_2.5 for children consisted of five components:combined sources of coal and vehicle emission, oil-burning ash, industrial dust, construction dust, and soil dust; while the sources for indoor exposure to PM_2.5 could contain:combined source of coal and vehicle emission, oil-burning ash, soil dust, and construction dust.