No keen observer of city, countryside or shore can have failed to notice that a direct consequence of man’s increasingly reckless exploitation of the earth’s natural resources is the contamination and destruction of the environment on which he depends to support his very existence. Man is the dirtiest of the animals. In UK, the average person produces about 2 lb (900 gm) of junk every day and this is only a third of the US figure. All over the world, cities from Sydney to Milan, New York to Los Angeles, suffer from acute problems of air pollution caused by the burning of domestic and industrial waste, coal and heavy oils for heating, and light hydrocarbon fuels by aircraft and motor vehicles. The home probably comes top of the league of earth-polluters. Sewage and garbage – particularly the packaging materials in which all consumer products now seem to be double wrapped not only represent vast quantities of apparently useless waste materials but also a criminal misuse of the earth’s precious and dwindling stock of natural resources. ‘Planned obsolescence’ in domestic products, if in the short run, commercially desirable and the seemingly unavoidable consequence of technological progress, also results in vast accumulations of untreated junk littering both townscape and countryside.
Particularly great problems are posed by synthetic plastics which are not ‘bio-degradable‘, that is which cannot be naturally broken down and reused in biological cycles. Industry produces its share of pollution from the great spoil heaps associated with quarrying and mining to the air pollution issuing from chemical and metallurgical processes and from coal and oil-fired electricity generating stations. A third more specialized type of pollution occurs when intensive agriculture employs herbicides, insecticides and inorganic fertilizers which break down to harmful residues.
The natural concentration in the course of biological food chains of the originally minute concentrations of these residues which enter rivers and thus the oceans, can result in sudden catastrophic drops in the fertility species at the end of the chains. The remedies for pollution are clear once its sources are identified. Air pollution results both from burning wastes from home and factory and fuels for heating and transport and from certain industrial processes which release dust and dangerous chemicals into the atmosphere. The development of more efficient means of burning fuels (through carbon dioxide rather than the poisonous carbon monoxide) and processes for removing dust from factory fumes (using electrostatic precipitators) offer partial solutions to air pollution. The air is also the medium carrying noise pollution from aircraft traffic and industrial processes which has so greatly increased during the 20th century.
In modern cities complete silence is a most unusual experience. Solutions in noise pollution come from a combination of quieting the sources of noise and soundproofing homes and places of work. Man uses more water than he does any other natural resource. Although supplies of water from precipitation are indefinitely renewable, in using them, man contaminates the water with an increasing burden of dissolved and suspended refuse. As a result, he not only drastically reduces the value of his water resources but eventually poisons the seas and oceans, destroying all marine life. The solution to water pollution is clear; effluent water must be purified before it is discharged into rivers. Conservation, the rational and well-managed exploitation of the earth’s natural resources, is the other side of the pollution coin. The recycling of waste products, particularly of used paper and metallic products, not only reduces the problem of pollution but also conserves supplies of timber and metal ores.
As the world runs short of energy producing minerals and conservationists become increasingly concerned at the disturbing of the ecological balance in rivers into which water, warm with the waste heat of industry, is discharged, more efficient insulation of homes and the beneficial employment of thermal waste, thus offer relief to problems, both of thermal pollution and of energy conservation. With water itself becoming daily more precious, the elimination of pollution and the desirability of re-use come to be seen as identical causes. Conservation of a second kind is concerned with the protection and preservation of as wide a range of living species as possible. Every animal and plant represents an irreplaceable reservoir of genetic material available to be used for the benefit of mankind; the extinction of any one of them would be a serious loss, not only to science, but also to the world at large. The very success of mankind has destroyed the natural habitats of many species, so careful management of the local environment is necessary if such species are to be preserved.