What gases make up photochemical smog?

Photochemical smog primarily consists of ground-level ozone (O₃), nitrogen oxides (NOₓ), and volatile organic compounds (VOCs). These pollutants react in the presence of sunlight, resulting in the formation of secondary pollutants. Other components can include particulate matter and various secondary products like peroxyacetyl nitrate (PAN). This type of smog is commonly associated with urban areas and can have adverse health effects.