Air Pollution

pollutants which contaminate the air

Air pollution is a chemical, particulate matter, or biological agent that modifies the natural characteristics of the atmosphere. The atmosphere is a complex, dynamic natural gaseous system that is essential to support life on planet Earth.  Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems.
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Noun
1. pollution of the atmosphere; "air pollution reduced the visibility"
(hypernym) pollution
(hyponym) acid rain, acid precipitation

The presence of contaminants or pollutant substances in the air that interfere with human health or welfare, or produce other harmful environmental effects.

One or more chemicals or substances in high enough concentrations in the air to harm humans, other animals, vegetation, or materials. Such chemicals or physical conditions (such as excess heat or noise) are called air pollutants.