1.3 O3
Ozone is an oxidant species formed predominantly from nitrogen dioxide
and non-methane volatile organic compounds in the
atmosphere.1,3 Peak season AQG and interim target
levels were set based on the pollutant-attributed increase in all-cause
non-accidental mortality, with moderate certainty evidence, and
respiratory mortality, with low certainty evidence. 24-hour levels were
set based on all-cause non-accidental mortality, with high certainty
evidence.
- AQG level (µg/m3):
- Peak season exposure: 60
- 24-hour exposure: 100
- Interim Targets (µg/m3):
- Peak season exposure: 100, 70
- 24-hour exposure: 160, 120
- Health outcomes : all-cause mortality, respiratory mortality,
asthma-related hospital admissions and emergency room visits
- Causality :
- Peak season exposure : likely causal for respiratory effects;
suggestive of causality for all-cause mortality
- 24-hour exposure : suggestive of causality for all-cause
mortality; causal for respiratory effects