الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
Pollution is a highly emotive word at the present time, conjuring up visions of imminent disaster to the environment and to the human race. Man’s activities have resulted in an increasing circulation of naturally occurring substances and the massive introduction of synthetic chemicals in the environment, there are more than chemical substances in use in the world today and this figure is increasing by year. Even in cases of food and drink untreated with synthetics and in pure air there are large numbers of substances that are not necessary to the health of man. Many of these substance S are toxic at low levels. Of course, any substance if not eliminated, will ultimately reach a toxic level. The progress of man, since his emergence from the Stone Age can be measured in terms of his increasing technologic use of metals. This increase has been a hazard to his health from the time metals were fashioned into spears to the present-day exposures involving space - age melts, alloys, or salts. Thus, exposure and possible health hazards also refiect the advancement of civilization. Serious environmental.