(Journal of the Air & Waste Management Association) Looking at literature on the effects of nitrogen dioxide on the odds of respiratory illness in children. Three quantitative methods for the synthesis of this evidence produced slightly different results, but the conclusion from all of them is that there is a 20% increase in the odds of respiratory illness in children exposed to a long-term increase of 30 micrograms per cubic meter of nitrogen dioxide, which is comparable to the increase resulting from exposure to a gas stove.
Hasselblad, V., Eddy, D., & Kotchmar, D., (1992) Synthesis of Environmental Evidence: Nitrogen Dioxide Epidemiology Studies, Journal of the Air & Waste Management Association, 42:5, 662-671, https://www.tandfonline.com/doi/abs/10.1080/10473289.1992.10467018