Associations between indoor VOCs and childhood asthma in Shanghai, China: an analysis stratified by frequency of window opening during night

Abstract

Few studies pay attention to the possible associations between indoor VOCs and childhood asthma in Shanghai considering the effect of household ventilation. From March 2013 to December 2014, we collected air samples from 358 children's bedrooms in Shanghai, China. Information on childhood asthma, environmental exposures, and lifestyle behaviors was collected. Two-sample of Mann-Whitney U test, bivariate logistic regressions, and multiple logistic regression were used to obtain the association between VOCs and childhood asthma. Association analysis stratified by frequency of window opening during night was conducted to explore its possible effect on the target association. High concentrations of toluene and dodecane were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. In the bedrooms with low frequency of window opening during night, high concentrations of toluene, dodecane, and TVOC were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. Our results indicate that exposure to VOCs may be a risk factor for childhood asthma, especially in the bedrooms with poor ventilation during night. Family avoidance behaviors of household ventilation should be considered in the study of associations of household VOCs with childhood asthmatic symptoms.