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Factsheet on WHO AQG - Health Effects of Short-Term Exposure to NO2, O3 & SO2 on Asthma


In 2021, the World Health Organization (WHO) published revised recommendations for ambient air quality (WHO 2021). To support this update, WHO published a review paper in 2021 evaluating the best available evidence on the effects of short-term exposure to nitrogen dioxide (NO2), ozone (O3), sulphur dioxide (SO2) and asthma exacerbations (Zheng et al. 2021). Specifically, the research published updated quantified risk ratios for exposure to NO2, O3 and SO2 on emergency room visits and hospitalisations.