The mad rat race among nations over the globe for development jeopardised the health of man itself. Progress in agriculture and industry is taken a general criterion of development of any country. This craze resulted into unlimited exploitation of every bit of natural resource. The splendid plentifulness of nature is a heritage that should be conserved for future generations and not be spoiled.
Such activities of man had adverse effect on all forms of living organisms in the biosphere. The earth planet alongwith the atmosphere (air, land, water) that sustains life is called the biosphere. Biosphere extends into about 7 km of the earth surface itself, downward into the ocean to depths of about 10-67 km and vertically into the air to about 10 km, where life is found to exist.
Unlimited exploitation of nature by man disturbed the delicate ecological balance between living and non-living component of the biosphere. The unfavorable conditions created by man himself threatened the survival not only of man himself but also other living organisms. The number of the species likely to become rare, threatened, endangered or near extinction in the Red Data Book of the IUCN is increasing with time. It is very common to find warnings at public places, reading as "Air unfit for breathing", "Water unfit for drinking", "Do not eat fish caught here" and so on.
India today is one of the first ten industrialised countries of the world. Today we have a good industrial infrastructure in core industries like metals, chemicals, fertilisers, petroleum, food etc. What has come out of these? Pesticides, detergents, plastics, solvents, fuels, paints, dyes, food additives etc. are some examples. Due to progress in atomic energy, there has also been an increase in radioactivity in the biosphere. Besides these, there are a number of industrial effluents and emissions particularly poisonous gases in the atmosphere. Mining activities also added to this problem particularly as solid waste.
Thus, pollution is a necessary evil of all development. Due to lack of development of a culture of pollution control, there has resulted a heavy backlog of gaseous, liquid and solid pollution in our country. It is to be cleaned. Thus pollution control in our country is a recent environmental concern. Not only in India, but in developed Western World also, pollution is a scare-word. Pollution is a man-made problem, mainly of effluent countries. The developed countries have been in a mad race to exploit every bit of natural resource to convert them into goods for their comfort, and to export them to needy developing world. In doing so, the industrialised countries dump lot of materials in their environment which becomes polluted. In one way pollution has been in fact "exported" to developing countries.
What is pollution? Pollution is an undesirable change in the physical, chemical or biological characteristics of air, water and soil that may harmfully affect the life or create a potential health hazard of any living organism. Pollution is thus direct or indirect change in any component of the biosphere that is harmful to the living component(s), and in particular undesirable for man, affecting adversely the industrial progress, cultural and natural assets or general environment.
What are pollutants? Any substance which causes pollution is called a pollutant. A pollutant may thus include any chemical or geochemical (dust, sediment, grit etc.) substance, biotic component or its product, or physical factor (heat) that is released intentionally by man into the environment in such a concentration that may have adverse harmful or unpleasant effects. A pollutant has also been defined as "any solid, liquid or gaseous substance present in such concentration as may be or tend to be injurious to the environment". Pollutants are the residues of things we make, use and throw away. There are many sources of such pollutants. The lakes and rivers are polluted by wastes from chemical and other factories, and the air by gases of automobile exhausts, industries, thermal power plants etc.
There has grown up a serious concern all over the world about the rivers turning murky, fish rotting on sea shores, trees withering, cities choking with foul air, toxic chemicals being cycled into food stuffs and disease epidemics appearing so frequently.
