Term: air pollutant
https://doi.org/10.1351/goldbook.A00194

Definition:
A substance, gaseous material or aerosol which has been introduced into the air (either by human activity or by natural processes) in sufficient concentration to produce a measurable effect on humans, animals, vegetation or materials (monuments, etc.): SO2, NO2, H2S, CO, hydrocarbons, etc.

Related Terms:
1) aerosol (http://doi.org/10.1351/goldbook.A00176).
2) hydrocarbons (http://doi.org/10.1351/goldbook.H02889).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2172 (https://doi.org/10.1351/pac199062112167)

Citation: 'air pollutant' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00194

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