Japan Environment and Children's Study Programme Office, Health and Environmental Risk Division, National Institute for Environmental Studies, Tsukuba, Japan; Department of Public Health, College of Public Health, China Medical University, Taichung, Taiwan.
Japan Environment and Children's Study Programme Office, Health and Environmental Risk Division, National Institute for Environmental Studies, Tsukuba, Japan.
Environ Res. 2021 Jun;197:111135. doi: 10.1016/j.envres.2021.111135. Epub 2021 Apr 8.
Volatile organic compounds (VOCs) are major indoor air pollutants. Quantification of indoor concentrations of VOCs and identification of factors associated with these concentrations can help manage indoor air quality. This study measured the concentrations of VOCs and inorganic gaseous pollutants in around 5000 households in Japan and utilised a random forest model to estimate these concentrations and identify important determinants. The homes of 5017 randomly selected participants in the Japan Environment and Children's Study (JECS) were visited twice, when the children were aged 1.5 and 3 years. Twelve VOCs and inorganic gaseous pollutants were measured during 7 days by passive samplers. Various factors in these households, including household appliances, building characteristics, cooking styles, use of consumer products, renovation, pets, personal behaviours and ventilation were recorded. A random forest model with recursive feature elimination was utilised to identify factors predictive of VOCs and inorganic gaseous pollutants. Toluene, formaldehyde and acetaldehyde were the dominant indoor VOCs. The 95th percentiles of indoor p-dichlorobenzene concentrations at 1.5 and 3 years were 67 μg/m and 71 μg/m, respectively. Random forest models with coefficients of determination ranging from 0.34 to 0.76 outperformed the traditional linear regression models. Factors associated with indoor VOC and inorganic gaseous pollutant concentrations included their outdoor concentrations, indoor and outdoor temperature and relative humidity, month of the year, hours windows were open, kerosene heater use and times of operation and building age. The results provided basic descriptions of indoor VOCs and inorganic gaseous pollutants in Japan and identified several determinants of these concentrations. These determinants should be considered to maintain indoor air quality. These results can be used in epidemiological assessments of the effects of VOCs and inorganic gaseous pollutants on health in children.
挥发性有机化合物（VOCs）是主要的室内空气污染物。量化室内 VOC 浓度并确定与这些浓度相关的因素有助于管理室内空气质量。本研究测量了日本约 5000 户家庭中 VOCs 和无机气态污染物的浓度，并利用随机森林模型来估计这些浓度并确定重要的决定因素。日本环境与儿童研究（JECS）中 5017 名随机选择的参与者的家庭在儿童 1.5 岁和 3 岁时被访问了两次。在 7 天内通过被动采样器测量了 12 种 VOCs 和无机气态污染物。记录了这些家庭中的各种因素，包括家用电器、建筑特征、烹饪方式、消费品使用、装修、宠物、个人行为和通风。利用具有递归特征消除的随机森林模型来识别预测 VOCs 和无机气态污染物的因素。甲苯、甲醛和乙醛是主要的室内 VOCs。1.5 岁和 3 岁时室内对二氯苯浓度的第 95 百分位数分别为 67μg/m 和 71μg/m。决定系数在 0.34 到 0.76 之间的随机森林模型优于传统的线性回归模型。与室内 VOC 和无机气态污染物浓度相关的因素包括其室外浓度、室内外温度和相对湿度、一年中的月份、开窗时间、煤油炉使用情况以及运行时间和建筑年龄。结果提供了日本室内 VOCs 和无机气态污染物的基本描述，并确定了这些浓度的几个决定因素。应考虑这些决定因素来维持室内空气质量。这些结果可用于评估 VOCs 和无机气态污染物对儿童健康影响的流行病学研究。
