Photochemical Smog Not to be confused with industrial smog, photochemical smog is air pollution produced by the action of sunlight on nitrogen oxides, hydrocarbons, and other pollutants created from fossil fuel combustion. Industrial smog is smoke and sulfur dioxide produced from the burning of coal combined with fog. A portmanteau word combining smoke and fog, the term was popularized by H. A. Des Voeux in his report to the Manchester Conference of the Smoke Abatement League of Great Britain in 1911.
Photochemical smog requires neither smoke nor fog.
When high concentrations of these pollutants accumulate and interact with sunlight, a chain reaction occurs. O 3 And voila, the chain reaction commences. VOCs are released in vehicle exhaust gases and are emitted by the evaporation of solvents and motor fuels. Precipitation or moderate winds can alleviate photochemical smog as the pollutants are washed away or replaced with fresh air, respectively. Photochemical smog can cause eye, nose, and throat irritations, impaired lung function, headaches, and coughing and wheezing.