8.3.10 (HL)—Tropospheric ozone direct impacts

Direct tropospheric-ozone effects include biological damage to plants and airways and physical deterioration of fabrics and rubber exposed to the gas.

Classify the exposed receptor first. Ozone can damage plant membranes, irritate eyes and inflame airways; it can also oxidize outdoor fibres and rubber. These direct effects are distinct from later healthcare or productivity costs.

A high-ozone episode can reduce plant photosynthesis and make an outdoor rubber seal crack faster.

Indirect: the direct airway injury leads to healthcare costs; classify the effect in the chain.

‘Ozone’ is not automatically good or bad; stratospheric protection and tropospheric exposure are different contexts.