ABSTRACT
Mercury has been used by humans for at least 2300 years, most recently as a fungicide in agriculture, in the manufacture of chlorine and sodium hydroxide, as a slime control agent in the pulp and paper industry, in the production of plastics and electrical apparatus, and in mining and smelting operations. Mercury burdens in some environmental compartments are estimated to have increased up to 5 times precultural levels, primarily as a result of human activities. The construction of artificial reservoirs, for example, which release mercury from flooded soils, has contributed to the observed elevation of mercury concentrations in fish tissues from these localities. Elevated levels of mercury in living organisms in mercury-contaminated areas may persist for as long as 100 years after the source of pollution has been discontinued. One major consequence of increased mercury use, coupled with careless waste disposal practices, has been a sharp increase in the number of epidemics of fatal mercury poisonings in humans, wildlife, and aquatic organisms. Most authorities agree on six points:
1. Mercury and its compounds have no known biological function, and the presence of the metal in the cells of living organisms is undesirable and potentially hazardous.
