5 Sources of Pollution
Pollution is defined as an alteration in the physico-chemical and biological nature of air, water and soil that ultimately affects the whole environment. It also specifies its hazardous impacts on living organisms (both flora and fauna), other environmental systems and non-living material.
Pollution is caused by anthropogenic (man-made) or natural activities. Examples of natural pollutions are volcanic eruptions, forest fires, floods caused etc. Incomplete technology lacking close integrated systems is the main cause of man-made pollution.
Today, the problem of pollution has become a major challenge to scientists, environmentalists and humanists as the pollution of various components has gone to such an extent that we are unable to breath fresh air, drink fresh water and eat pure food. If man has to survive, he has to fight and overcome this gigantic problem before it swallows him and his very existence.
Sources of Pollution
Pollution may be caused by several sources depending upon the nature of pollutants:
1. Solid Wastes as a Source of Pollution
Solid Wastes may be domestic or industrial in nature. Various solid wastes can be categorised as follows:
- Industrial wastes, e.g. particulate wastes from various industries such as glass fragments, leather pieces, rubber pieces etc.
- Domestic Wastes, e.g. garbage of kitchen, slaughter houses etc. These may be combustible (such as leaves, twigs, papers etc.) or non-combustible (such as crockery, plastics, glass etc.) in nature.
- Sewage, e.g. human and animal excreta, domestic effluents, detergents etc. (solid faecal is called sludge)
(iv) Agricultural Wastes, e.g. plant and animal residues, broken twigs, wood fractions, fruits, pesticides, fertilizers etc.
2. Liquid Wastes as a Source of Pollution
Industrial effluents and domestic wastes in the form of liquid are the major sources of water and soil pollution. Industrial pollution may leach the lethal magnitude. Liquid discharges from chemical factories, refineries, breweries, tanneries etc. contain acids, alkalies, oil and dissolved heavy metals which enter the river water and adversely affect the aquatic life and impair its self-purification system.
Liquid wastes from domestic sources may be of inorganic or organic nature. Inorganic liquid wastes include soap water and detergent water from bathing and washing clothes whereas organic wastes include kitchen garbage, faecal water, urine etc.
Run off from agricultural fields carry residual fertilizers, pesticides, biocides etc. which enter the water streams and harm the aquatic life.
3. Gaseous Wastes as a Source of Pollution
The common gaseous pollutants like carbon monoxide, sulphur oxides, nitrogen oxides, hydrogen sulphide etc. are frequently released from various industries and automobile exhausts. Pollution resulting from gaseous wastes is the one of the most dangerous and lethal type. Life on earth is dependent upon the air we breathe and if this source of life is contaminated and polluted by lethal gaseous discharges, the very existence of all living organisms is threatened.
4. Energy Wastes as a Source of Pollution
A significant addition to the sources of pollution are the invisible pollutants i.e. pollutants without mass or weight and invisible to the eyes. Examples of such pollutants are heat and radioactive emissions. Radioactive emissions are most hazardous, and their cumulative effects are far reaching and damaging to the genetic makeup of living organisms.
5. Noise as a Source of Pollution
Unwanted sound or noise above the particular level in the atmosphere is an important pollutant. Indiscriminate and continuous use of radios, traffic horns, public broadcasting systems etc. are common sources of noise pollution. Aeroplanes and supersonic jets also produce noise of high intensity which may sometimes rupture the ear drum and cause irreparable damage to the brain.