الفهرس 
acknowledgmentOnly 14 pages are availabe for public view
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Abstract
Only in recent decades has it become evident that man’s impact on biological events in the world is far from trivial. Nowhere is this conclusion more evident than in the present concern over the degradation of our environment. One reflex- ion of this concern is the extensive literature on the toxi- city of pollutants, particularly heavy metals, on living organisms.
Heavy metals discharged into the marine environment can affect the marine organisms as toxicants dissolved in the sea water or as toxicants present in the food of these orga- nisms. Direct up-take of heavy metals from the surrounding sea water by marine organisms is thus only one of the possible routes of entry.
Heavy metals in trace amounts are normal constituents of marine organisms and some of them such as zinc and copper are absolutely essential for normal growth and development. In coastal regions, these metals are normally supplied to the sea in river water or as wind blown material following the weathering of rocks (Schutz and Turekian,1965). However, at the present time, additional quantities of metals are being added to coastal regions from industrial effluents, from.