Air pollution is caused mainly by man made products and artificial processes which result in harmful substances being released into the atmosphere. The pollutants of the air are divided into two categories, primary and secondary. The primary pollutants pertain to those which are directly released from processes in the form of pollutants into the air. The secondary pollutants include elements and compounds which are released into the air and then form harmful substances which can pollute the environment.
Some of the most common sources of air pollution are sulfur oxides, nitrogen oxides, carbon monoxide, carbon dioxide and volcanic compounds. All of these are formed as a result of fire or combustion in complete or incomplete form. Other pollutants include particulate matter, Chlorofluorocarbons, ammonia, toxic metals as well as radioactive waste. Other more commonly available pollutants are smog, smoke, and ground level ozone.
Industries are one of the main sources of air pollution in the world. These tend to emit harmful oxides, which are carbon or nitrogen based resulting in release of CFC’s which can harm the environment through acid rain. Aside from this the waste discharged by the industries is highly contaminating and harmful as well as it is volatile in nature.