Bad air quality" and "Air quality" redirect here. For the obsolete medical theory, see Bad air. For the measure of how polluted the air is, see Air quality index. For the properties of air, see Qualities of air.
Air pollution from a fossil-fuel power station
Air pollution is the introduction of particulates, biological molecules, or other harmful materials into Earth's atmosphere, causing disease, death to humans, damage to other living organisms such as food crops, or the natural or built environment. Air pollution may come from anthropogenic or natural sources.