Indoor air pollution in kindergartens is a stronger predictor of preschool wheezing than household pets and passive smoking.

BACKGROUND

The quality of air in kindergartens, where children spend a significant part of their time, is an important determinant of health.

OBJECTIVE

This study aimed to explore the relationship between indoor air pollution in kindergartens and wheezing syndrome in preschool children.

METHODS

Air pollution, specifically the concentration of particulate matter (PM), was measured in 24 kindergartens. A total of 1,794 parents of preschool children were surveyed about respiratory symptoms and environmental factors affecting their children.

RESULTS

The mean age of the children was 4.07 (± 1.44) years, and 50.9% were males. Wheezing history was reported in 5.8% of children, while separately evaluated physician-diagnosed bronchiolitis in 11.1% and asthma in 2.6%. One third of children were exposed to smoking and 44.2% had pets at home. Allergic rhinitis and eczema, having siblings, higher concentrations of PM2.5 and PM1 in kindergarten environments, and proximity to railways were independently associated with an increased risk wheezing of wheezing in preschool children.

CONCLUSION

The association between wheezing and indoor PM2.5 and PM1 concentration in kindergartens outweighed other common household exposures, such as pet ownership and secondhand tobacco smoke. Therefore, improving indoor air quality through effective control of air pollutants, installation of vegetative barriers near kindergartens that promote particulate matter dry deposition from outdoor air pollution sources, and adherence to indoor air quality guidelines are essential for preventing recurrent wheeze in early childhood.