Abstract:
Mercury is a metal toxic to humans. Man has always been exposed to small amounts of mercury because of its natural occurance in the inorganic, organic and elemental forms. Organic mercury is formed from elemental and inorganic divalent mercury by microorganisms. Elemental mercury is found in hot springs and young volcanoes. Inorganic divalent mercury occurs principally as cinnabar (mercuric sulfide) deposits which are ubiquitous throughout the earth's crust in both sedimentary and igneous geological formations. Heavy coastline cinnabar deposits ring the Pacific Ocean and Mediterranean Sea and are also found in the north-south Atlantic ridge.
Mercury has spread heavily into other areas by the uses man has made of it: The mercury cell utilized in the commercial production of chlorine and sodium hydroxide has contaminated nearby waterways because of its heavy losses from the cell. The paper industry has employed these cells as a source of chlorine to bleach paper and, in addition, has added organic mercury compounds to the paper itself as fungicides. The paint industry has incorporated organic mercury in most paints as preservatives, and anti-fouling paints for ship bottoms can contain mercury as a major component. In agriculture, aryl mercury compounds are frequently employed for treatment of tress and seeds against fungal growth. Mercury is used as a medicine (although this practice has diminished), as a preservative for solutions (such as contact lens solutions), as a catalyst, for electrical switches, as flotation supports, for barometric and manometric devices, and in amalgams for ore refining and for dental fillings.
Taken from the beginning of thesis.