Organochlorines are a large class of chemicals including industrial organics, agricultural organics, by-products of anthropogenic activities, and chemical transformation products. They are important environmental contaminants due to their high stability and persistence in the environment, high big-accumulation potential, potential for high chronic toxicity, and as a result of the large quantities which have been released into the environment. Source: Department of Indian Affairs and Northern Development

  Polychlorinated biphenyls (PCBs) Hexachlorobenzenes (HCBs) Hexachlorocyclohexane (HCH) DDT DDE Mirex

Chlordane Toxaphene Endrin Aldrin Dieldrin Lindane Dioxins Furans


1 ) Industrial Organics Sources: incineration volatilization


PCBs (polychlorinated biphenyls)

HCBs (hexachlorobenzene)


 2) Agricultural Organics Sources: spray drift, evaporation, volatilization, wind erosion

 HCH (hexachlorocyclohexane)

 Lindane DDT (dichlorodiphenyltrichloroethane)  DDE  Chlordane  Toxaphene  Endrln




  Arsenic Cadmium Selenium  

3) Anthropogenic By-Products


4) Chemical Transformation Products


 Lead Mercury  Heavy Metals

 Heavy metals are metals of high specific gravity. Metals are required for the life processes of animals, including man. The body requires substantial amounts of some metals (for example, sodium and iron) and has a high tolerance for their absorption. Other metals, such as the "micro-nutrients" copper and zinc, are required in much smaller amounts, and the body has a lower tolerance. Finally, there are metals which are not essential to life processes and are toxic to both man and other species at lower levels.

 The effects of such substances vary with the metal. In some cases, heavy metals attack nervous tissues by enzymatic blocking of biochemical reactions. More frequently, they destroy excretory organs, such as the liver and kidneys.


Beryllium Mercury Thallium Boron Nickel Titanium

Cadmium Selenium Vanadium Lead Zinc

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