Summary

In 2021, the World Health Organisation (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 sulphur dioxide (Orellano et al. 2021). Specifically, the research published updated quantified risk ratios for exposure to sulphur dioxide (SO2) on all-cause mortality (people dying earlier than they otherwise would have).