Environmental Pollution

Pollution may be defined as addition of undesirable material into the environment as a result of human activities. The agents which cause environmental Pollution are called Pollutants. Primary pollutants are emitted directly from identifiable sources. Secondary pollutants are produced due to chemical creation among primary pollutants.

Types of Environmental Pollution

- Pollution may be of the following types Air Pollution, Noise Pollution, Water Pollution, Soil Pollution and Thermal Pollution.

Air Pollution

It may be defined as the presence of any solid, liquid or gaseous substance including noise and radioactive radiation in the atmosphere in such concentration that may be directly and indirectly injurious to humans or other living organisms, plants, property or interferes with the normal environmental processes. Air pollutants are two types

(1) Suspended particulate matter (Dust, smoke, soot, pollen and soil particles) and

(2) Gaseous pollutants like carbon dioxide (CO²), NOx etc.

Noise Pollution

Noise by definition is 'sound without value' or any noise that is unwanted by the recipient.

Noise level is measured in terms of decibels (dB). WHO (World Health Organization) has prescribed optimum noise level as  45 dB by day and 35 dB by night. Anythings above 80 dB is hazardous.

Water Pollution

Water Pollution is caused by a variety of human activities such as industrial, agricultural and domestic. Agricultural run off laden with excess fertilizers and pesticides, industrial effluents with toxic substances and sewage water with human and animal wastes pollute our water thoroughly.

Soil Pollution

Addition of substances which adversely affect the quality of soil or its fertility is known as soil Pollution. Soil can be polluted by pathogenic organims, organic and inorganic chemicals and toxic metals.

Thermal Pollution

The waste heat from the boilers and heating processes increases the temperature of water. Discharge of hot water may increase the temperature of the receiving water by 10 to 15°C above the ambient water temperature.