As a consequence of the activities of modern industry and agriculture, many made-made organic compounds have found their way into our environment, and by persisting there for varying periods of time have caused concern to society. Why do some chemicals persist while others disappear? Detailed answers to this question require an understanding of the degradative segment of the earth's carbon cycle, most of the reactions of which are catalysed by enzymes used by microbes. These organisms owe much of their degradative expertise to their ability to render oxygen gas chemically reactive. This is a process that would be extremely dangerous for any living organism if it were carried out in a haphazard or accidental fashion; but when catalysed and cantrolled by enzymes (oxygenases) of micro-organisms, reaction sequences are started that result in biodegradation of compounds that resist the enzymes of all other living forms.

The use of traditional Western concepts of disease (i.e. the ‘germ’ theory) has guided the use of scientific knowledge and technologies in the Control of acute infectious diseases (Gori & Peters, 1975; Trosko & Chang, 1978c). The intervention of all sorts of technologies has prolonged the life expectancy, allowing more people to reach the limit of what appears to be a rather fixed life-span (Hayflick, 1976). At the same time, human beings have used technologies to alter out dependence on the natural enviroment We intervene on many levels to minimize threats to our dependence on natural forces for food (e.g. agricultural technology, food additives), for water (e.g. wells or dams), for health (e.g. instituting sanitary measures or using drugs), for protection against the elements (e.g. wearing clothes, building homes with heaters and air conditioners) and for pleasure (e.g. snowmobiles, etc.). It is now extremely clear that much of the ‘effluents of our technological affluence’ can be harmful to living systems.