General Knowledge

Hazardous Effect of Pollution

Hazardous Effect of Pollution

Greenhouse Effect

It is the heating of the Earth and its objects because of trapping of IR radiations by carbon dioxide (CO2), methane (CH3), nitric oxide (NO), ozone (O3), chlorofluoro carbons (CCFCs), and water vapours.

Global Warming

It is a result of an increased concentration of greenhouse gases. It may result in melting of ice caps and glaciers, spreading of several infectious diseases like malaria and sleeping sickness.

Acid Rain

It has pH less than 5. It is due to the presence of oxides of nitrogen and sulphur in air that dissolve in rain water and form nitric acid and sulphuric acid.

» It damages the buildings and other structures made up of limestone and results in several diseases such as skin infections.
» pH of normal rain water is 5.6


These are the substances that contaminate the environment and are of two types:

1. Primary Pollutants :
These persist in the environment in the form they are produced, e.g., sulphur dioxide (SO2), nitrogen dioxide (NO2), etc.

2. Secondary Pollutants :
These are the products of reaction of primary pollutants, e.g., PAN (Perocyacylnitrates), Ozone (O3), Aldehyde, etc.


It is a consequence of particulate pollution and is of two types:

1. Classical Smog :
It is also called London type smog. It is reducing in nature.

2. Photochemical Smog :
It is also called Los Angeles smog. It occurs in warm, dry, and sunny climate by the action of sunlight on unsaturated hydrocarbons and nitrogen oxide. It is oxidizing in nature.

Tropospheric Pollution

Presence of undesirable solid or gaseous particles in the air. Gaseous air pollutants are S, N and C, H2S, hydrocarbons, ozone, and other oxidants. Particulate pollutants are dust, mist, fumes, smoke, smog, etc.

Stratospheric Pollution

Stratospheric pollution means depletion of ozone layer (ozone hole) by certain compounds like chlorofluorocarbons (CFCs), oxides of nitrogen (which are released into upper atmosphere from engines of supersonic transport planes).