Rankings / Toxins

Ozone (tropospheric)

Toxins · Air pollution

High priority

air-pollutant
7.1 / 10
HIGH
Mag 8.0 Ev 8.0 Prev 5.0

What this is

Standard HEPA removes particles but not ozone — activated carbon needed. Some 'air purifiers' (ionizers, some UV lamps) actually generate ozone — avoid. Peak ozone is late afternoon in summer; morning/evening outdoor exercise is safer.

Mechanism

Ground-level ozone forms from NOx + VOCs + UV; strongest photochemical smog component; airway irritant; cardiovascular effects; worst in hot sunny urban afternoons

Dose & route

Avoid outdoor exercise during afternoon ozone peaks; activated carbon filtration (not HEPA) needed to remove

This is an independent synthesis of published research by a non-clinician. Scores are opinions supported by citations, not prescriptions. See the full disclaimer and methodology for how this score was produced and what it does and doesn't mean.