The biosphere and ecosystem are self-sustaining. Nature maintains a balance in land, water, air and all the living organisms in the world. Any imbalance therein causes a chain reaction. Any amount of any kind of imbalance in the biosphere is called environmental pollution. Man is going to conquer the universe with the help of technological development, but this development has resulted in grave danger to the very existence of man. Today air is becoming foul, waters are no longer clean and forests are being cut down. If this continues, air and water would become unfit for the use of all living beings.
The grand industrial development, the successful green revolution, the transport explosion, the rapid growth of cities and haphazard management of natural resources, have adversely affected environmental balance. The pollution of air and water will soon reach a point when on place on the earth will remain safe. Due to large scale industrial and human settlement effluents, many rivers have turned murky. The large scale industrial wastes and oil released in the seas have started killing marine life.
There is no doubt that modern technological development has been the main instrument in polluting our air, oceans and rivers, etc. It is a matter of concern to all humanity that our rivers are turning murky, fishes are rotting on sea-shores, trees are withering, cities are choked with foul air and toxic chemicals are finding their way into our food. “Nature’s plentifulness is a heritage not to be squandered with impunity. It must be conserved for future generations or its bankruptcy will extinguish us all” is the observation of a well-known scientist. It appears that man has lost his capacity to foresee and forestall. He will end by destroying the earth and with it, of course, perish himself.
When the normal composition of air is changed, air becomes polluted. The main causes of air pollution are : (i) combustion, (h) manufacturing processes, (in) agricultural activities, (iv) use of solvents, and (v) nuclear energy programmes. Details of these are given in the table that follows.Combustion can be categorised mainly into three types, viz. fuel burning, transportation and refuse burning. All these categories of combustion release several types of gases which pollute the air. Automobiles, trains, aircrafts and other forms of transport are responsible for polluting the air with hydrocarbon, carbon monoxide, lead, nitrogen oxide and other oxygen products.
There are various types of manufacturing processes which cause air pollution. Chemical plants, metallurgical plants and plants for waste recovery may be put under this category. The pollutants released from these processes differ widely. Several types of gases and fumes are produced in these processess, which make the air unfit for human consumption. Agricultural activities are yet another source of air pollution. Spraying of pesticides and insecticides, use of chemical fertilizers and manures and burning of field wastes pollute the atmospheric air. Several types of solvents are used in spray-painting, polishing of furniture and appliances, dyeing, printing and dry cleaning. These solvents produce hydrocarbons and other organic vapours which mix with the atmosphere and pollute it. Nuclear energy programmes also pollute the air. Radioactive fallouts and fluorides are very dangerous pollutants.
Of late it has been realised that the pollution of the seas is going beyond the tolerable limit. Man uses large volumes of agricultural and industrial materials, whose waste products are dumped in the seas and oceans. Oceans and seas cover two-thirds of the earth’s surface and their pollution has very harmful effects on plants and animals.
Release of industrial wastes into rivers creates havoc. It is estimated that more than 5,000 tons of mercury enters the ocean per year as a result of dumping of wastes into rivers. Mercury concentration increases in fish, which may result in poisoning of the people and domestic animals, eating such fish. Fish from many lakes and seas in American countries have been declared unsafe to eat. Many people have suffered neurological disorders by eating such polluted fish. Lead is another pollutant of seas and oceans. Normal weathering processes and industrial discharges are the main source of its entry into the seas. Radioactive material released from nuclear tests is another dangerous pollutant.
Constant and loud noise is yet another health hazard. The noise pollution in Bomby city has touched 74 decibels. This is enough to damage about 15 per cent of hearing capacity in a decade. In big cities frequent mixing of sewer lines with the water-supply net-work causes drinking water pollution. Destruction of trees, birds and animals affects human environment adversely.
The effects of pollution on the climate ar/dangeror.s – though so slow and gradual as to be beyond easy recognition.” Air pollution results in the steady rise in the amount of carbon dioxide and dust particles in the atmosphere. Increase in carbon dioxide raises the earth’s temperature while increase in the dust particles decreases it. An increase either way means change away from the mean. According to an estimate dust particles can absorb 3 to 4 per cent of the sun’s radiation, and thus lower the earth’s temperature by about 0’4°C.
What would be the result of an appreciable change in the temperature of the earth ? It is estimated that a rise of 3’6°C in the earth’s temperature would melt the icecaps of the Antarctic and Arctic regions. As a result of this melting, the water levels of oceans would go up about 100 metres and most of the major cities of the world would be submerged under water, and the earth’s present coastline would be changed drastically. Scientists are of the view that such a stage may come after about 200 years at the present rate of pollution.
On the other hand it is estimated that the cooling brought about by increase in dust particles in the atmosphere may bring in the ice age. A drop of 4’0°C in the mean temperature of the earth may be sufficient to bring the ice age once again. But there is nothing to be scared of, as some scientists argue that between these two limits the opposing forces would maintain the heat balance.
Various measures may be adopted to control pollution. To trap smoke particles, chambers should be provided. Lofty smoke stakes should be built to counteract the danger of concentration of toxic gases. Gases should be discharged through exhaust pipes higher in the air. Chemical industries should not be allowed to be set up on the banks of rivers. The industries on the river banks should be ordered to discharge their wastes in the river only after treating them fully. The industries should be made to follow some absolute minimum standard of emission. Waste effluents should be subjected to anti-pollution treatment.
The growing automobile civilization is multiplying air pollution. Man is poisoning the biosphere. Nobody can save him from this danger unless he himself becomes alert. It is a grave danger for the present as well as the future, It is the solemn responsibility of the international community to protect the environment from pollution. Fortunately, in recent years there has been a world-wide awakening in this regard. In many international conferences concern has been expressed over this issue of vital importance to human life.
It would not be irrelevant to refer to the Bhumisutra in Atharva Veda, which says that our Rishis and seers worshipped the earth, mountains, lakes, rivers, plants, etc. They did it not as a bit of superstition, but they realised that there was a deep harmony behind all existend. and human beings have got to exist in harmony with their surroundings. They never tried to put the human race against nature. To this wisdom once again the human race is returning.
Environmental pullution is no longer only a fashionable catch-Word. It has infact become one of the most formidable threats to mankind. With the growing development of technology and growing world population, pollution is no longer restricted to a certain number of industrial countries but affects the ecological system of vtiit areas. As we become increasingly aware of our limited natural roiources, the protection and preservation of nature becomes a world-wide concern.
In view of the increasing awareness of the formidable dangers to mankind, many countries in the world have passed laws to prevent pollution. But it has been observed that anti-pollution lawn are not being obeyed everywhere. It is hard to understand why the laws being framed by Governments should vest all powers In Anti-pollution Boards composed of salarised employees with no direct stake in the outcome of their activities, denying the victims Of pollution any right. Given the will, it should not be too difficult to put teeth into the current laws against pollution. It is gratifying tillt lome action is being taken, though belatedly.