Air Pollution: Introduction

Air pollution is the introduction of harmful substances at an undesirable concentration into the Earth's atmosphere which make the air unsafe for living.

Air is precious and is essential for sustaining life on the planet. It provides oxygen required for respiration, carbon dioxide for photosynthesis, and nitrogen for synthesis of amino acids and proteins. The ozone layer in stratosphere absorbs harmful UV rays, thus protecting the living organisms from harmful effects of these radiations.

Any change in composition and quality of air caused by introduction of harmful substances can affect life on Earth severely. The main sources of air pollution are automobile emissions, burning of fossil fuels and industrial processes. Naturally occurring processes like volcanoes, dust storms, forest and grassland fires also cause air pollution.