When poisonous gases and harmful substances mix with air and make it impure, the air is said to be polluted.
Air pollution refers to any physical, chemical, or biological change in the air. It is the contamination of air by harmful gases, dust, and smoke that affects plants, animals, and humans drastically.
The causes of air pollution are:
Air pollution is caused when the air in the atmosphere gets filled with particulate matter.
The largest source of air pollution in cities is vehicle exhausts fumes.
Using household chemicals without adequate ventilation is a major source of indoor air pollution.
Volcanoes, dust storms, and forest fires are causes of natural air pollution.