1.4 NO2
NO2 is a trace atmospheric gas and strong oxidant that is both a threat to human health and implicated in climate change.1,3 Annual AQG and interim target levels were set based on the pollutant-attributed increase in all-cause non-accidental mortality, with moderate certainty evidence, and cause-specific respiratory mortality, with moderate to high certainty evidence. In addition, 24-hour levels were based on all cause non-accidental mortality and asthma-related hospital admissions and emergency room visits, with high certainty evidence.