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Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/929019
- Respiratory health effects of exposure to low-NOx unflued gas heaters in the classroom: a double-blind, cluster-randomized, crossover study
Marks, Guy B.;
Toelle, Brett G.;
Smith, Wayne T.
- The University of Newcastle. Faculty of Health, School of Medicine and Public Health
- There are long-standing concerns about adverse effects of gas appliances on respiratory health. However, the potential adverse effect of low-NOx (nitrogen oxide) unflued gas heaters on children’s health has not been assessed. Our goal was to compare the respiratory health effects and air quality consequences of exposure to low-NOx unflued gas heaters with exposure to non–indoor-air-emitting flued gas heaters in school classrooms. We conducted a double-blind, cluster-randomized, crossover study in 400 primary school students attending 22 schools in New South Wales, Australia. Children measured their lung function and recorded symptoms and medication use twice daily. Nitrogen dioxide (NO₂) and formaldehyde concentrations were measured in classrooms using passive diffusion badges.NO₂ concentrations were, on average, 1.8 times higher [95% confidence interval (CI), 1.6–2.1] and formaldehyde concentrations were, on average, 9.4 ppb higher (95% CI, 5.7–13.1) during exposure to unflued gas versus flued gas heaters. Exposure to the unflued gas heaters was associated with increased cough reported in the evening [odds ratio (OR) = 1.16; 95% CI, 1.01–1.34] and wheeze reported in the morning (OR = 1.38; 95% CI, 1.04–1.83). The association with wheeze was greater in atopic subjects. There was no evidence of an adverse effect on lung function. We conclude that classroom exposure to low-NOx unflued gas heaters causes increased respiratory symptoms, particularly in atopic children, but is not associated with significant decrements in lung function. It is important to seek alternative sources of heating that do not have adverse effects on health.
- Environmental Health Perspectives Vol. 18, Issue 10, p. 1476-1482
- Publisher Link
- U.S. Department of Health and Human Services
randomized controlled trial;
respiratory health effects;
- Resource Type
- journal article