Introduction to Air Pollution

Introduction to Air Pollution:
Air pollution means the presence of contaminants or pollutants in the atmosphere beyond tolerance limit that can cause health problems to all human beings on earth. The causes of air pollution can be both natural or man-made. Air pollutants are mostly gases or small particles which remain suspended in the air for very long time period.
Sources of Air Pollution:
The most characteristic sources of air pollution have always been combustion processes where the pollutant is smoke. Out of all combustion processes, the most dominant player responsible for pollution is automobiles. The burning of fossil fuels in automobiles releases enormous amount of sulfur and nitrogen oxides which are heavy air pollutants.
Apart from the automobiles, power sector is another major play in causing pollution. Humans are still dependent on fossil fuels for all their energy demands. Coal is the major source of energy in thermal power plants to produce electricity and is the dirtiest of fuel among all. Burning coal produces smoke which contains contaminants and when this smoke is released into atmosphere, these contaminants remain suspended in atmosphere for a long duration.
Air Pollution Scenarios:
Smoke has been the reason of urban air pollution since centuries because of the same reason. The use of coal throughout the centuries has caused cities to be very smoky places. The present scenario is not very different. Coal is still burnt in large quantities to produce electricity worldwide and is therefore one of the main source of pollution.
The world has now shifted to liquid and gaseous hydrocarbons like oil and natural gas to meet its energy demands. Though these fuels are considerably cleaner than coal but excessive use of these fuels have resulted in increased concentration of greenhouse gases like carbon monoxide, nitrogen oxides etc. in the atmosphere.
Effects of Air Pollution:
Pollutants have a wide range of effects with health problems being of most concern. Respiratory diseases tops the chart of health problems. The second major health problem is heart diseases caused due to increased level of carbon monoxide in the air. Pollutants are also involved in increasing cases of Asthma, Eye Irritation and a range of bronchial diseases.
Pollution also affect our environment and ecosystems. Acid rain is the result of increased amount of pollutants present in the atmosphere which gets dissolved with the rain water. This acidic rain caused serious harm to our natural environment and ecosystems. Fading shine of Taj Mahal, among world's seven wonders, is one of the example of how air pollution can impact our environment?
Air pollution control:
The need to control pollution was recognized in the earliest cities. The nineteenth century saw a growing interest in improving public health by controlling pollutants. Laws were formed to keep the pollutants downwind or outside the city.
Since then, as the environmental awareness has increased, a lot of precautionary measures have been taken by the governments and strict pollution laws have been imposed on industries to control pollutants. The improvements in technology and increased energy efficiency of engines have also helped in reduced emissions compared to a few decades ago.
For more detailed information, read our environment pollution guide.
Keshav Saini is an Engineer turned Environmentalist and is actively involved in Environment Protection activities. He started Environment About to spread awareness about environmental issues and to educate people about green living.