Air pollution is the release of gases, solids, or liquid aerosols into the atmosphere at rates that exceed the environment’s capacity to dilute or absorb them. It occurs when substances are present in concentrations high enough and for durations long enough to cause harm to human health, property, or atmospheric visibility.
Pollutants can be primary, released directly from sources like vehicles and factories, or secondary, formed through chemical reactions in the atmosphere. Major air pollutants include sulfur dioxide, nitrogen oxides, carbon monoxide, ozone, particulate matter, and lead. These pollutants can have far-reaching effects, contributing to issues like acid rain and global warming.