Air pollution

Today is our topic of discussion Air pollution

Air pollution

Definition:

Air is a predominantly physical mixture of a variety of individual gases enveloping the terrestrial globe to form the earth’s atmosphere. All forms of life depends on air. A man daily consumes about 1.5 kg food, 2.5 kg water and 15 kg of air.

Composition of air :

1. Nitrogen 78.1%
2. Oxygen 20.95%
3. Carbon-dioxide – 0.03%
4. Argon -0.93%
5. Traces of hydrogen, ammonia and ozone

Air pollution:

Air Pollution is defined as the presence in atmosphere of one or more air contaminants or combination thereof in such quantities which is harmful to man or his environment.

Source of air pollution/how open air is polluted:

1. Automobiles – Motor vehicles are a major source of air-pollution throughout the urban areas. They emit hydrocarbons, carbon monoxide, lead, nitrogen oxides and particulate matters which forms noxious smokes and fumes.

2. Industries Industries emits large amounts of pollutants into the atmosphere by combustion of
fuel. It also produces heat and other hazardous chemicals such as, hydrogen flouride, hydrochoric
acid, hydrogen sulphide etc.

3. Domestic sources – Domestic combustion of coal, wood and oil is a major source of smoke, dust,
suphur dioxide and nitrogen oxides.

4. Tobacco smoke – The most direct and important source of air-pollution affecting the health of many people is tobacco smoke. Even those who do not smoke may inhale the smoke produced by others (‘passive smoking’). moo smitouftabixoib uqlue of svilenaz

5. Others – These comprise burning refuse, incinerators, pesticide spraying, nuclear radiation etc.

Self-cleaning mechanism of open air pollution:

The following methods are regarded as ‘self- cleaning capacity’ of the environment –

Wind –

The wind is an active force in cleaning of polluted air. Wind reduces vitiated air and bacterial density. Thus it dilutes and sweeps away the impurities.

Plant life or ‘trees’ –

These utilises carbon-dioxide and produces oxygen. Some air pollutants are readily removed by vegetation. The establishment of ‘green belts’ between industrial and residential areas is an attempt to dilute the polluted air.

Raining –

Raining plays an immense role in removing suspended and gaseous impurities from ambient air.

Sunlight –

Direct sunlight helps to reduce bacterial count by oxidising impurities & killing microorganisms. UV-ray from sunlight also helps to eradicate bacterial spores.

See also :

• Cord Blood Banking Kit