Skip to content Meaning: Bushfire smoke is the dirty air produced when bush and grass burn— a mix of tiny particles (PM2.5/PM10), gases (like carbon monoxide and nitrogen oxides), water vapour and ash—that can sting eyes and throat, worsen asthma and heart conditions, and cut visibility; children, older adults, pregnant people, and anyone with breathing or heart issues are most at risk, even far from the fire line. Last updated:…