Pollution

Abstract

By pollution one usually understands the presence of any harmful substance in the air, water or land in sufficient concentration to affect the quality of human, animal or plant life. Although the origin of pollution is generally to be found in human activities, it would still exist without man since nature itself continually contributes to it, e.g. by oil seepage from undersea wells or by more spectacular phenomena such as forest fires or volcanic eruptions. There is therefore a natural level of various forms of pollution which would occur without human activities. Human pollution is not a problem of modern times, but has always accompanied man from the time he built his first towns. Pollution under its modern form, caused by the concentration of industry and ever-increasing numbers of people in large cities, can be dated back to the Industrial Revolution. Man began to get rid of his sewage and industrial waste by disposal in rivers, and with developing urbanisation and industrialisation the rivers in industrialised regions of the earth were gradually transformed into lifeless, open sewers. Industry also produced huge quantities of poisonous gases and nineteenth-century technology had no other remedy for these but to expel them into the air by numerous factory chimneys concentrated in a small area around towns.