Definition - What does Photochemical Oxidants mean?
Photochemical oxidants are the product of chemical reactions that occur between nitrogen oxide (NOx) and any of a host of different volatile organic compounds (VOCs). Common or well known photochemical oxidants include ozone (O3), hydrogen peroxide (H2O2), and peroxyacetyle nitrate (PAN). These photochemical oxidants are cause for concern, as they can have negative effects on human, plant and animal health.
Safeopedia explains Photochemical Oxidants
Organic compounds are chemicals that contain carbon and are found in all living things. Volatile organic compounds (VOCs) are organic compounds that easily turn to vapours and become highly flammable. These are released from burning fuel such as gasoline, wood or coal, solvents, natural gas etc.. When combined with nitrogen oxide they become photochemical oxidants like ozone and impact climate change significantly.