PCBsPolychlorinated biphenyls are mixtures of up to 209 individual chlorinated compounds, invented by Swann Chemical Company and manufactured by Monsanto until 1972.
Usage:
PCBs have been used as coolants and lubricants in transformers, capacitors and other electrical equipment because they do not burn easily and are good insulators.
Health effects and symptoms:
PCBs are pervasive in the environment and bioaccumulate in the food chain, causing health advisories for fish and other wildlife in some locations. Exposure to PCBs may cause acne-like skin conditions and rashes and neurobehavioral and immunological changes in children. PCBs are considered a probable human carcinogen by the U.S. EPA. Also, recent studies indicate that eating large amounts of PCB-contaminated fish may impair the memory and learning of adults.
Lead
A naturally-occurring bluish-gray metal found throughout the environment. Much of it is released from human activities including burning fossil fuels, mining and manufacturing.
Usage:
Lead has many uses, including the production of batteries, ammunition, metal products (solder and pipes) and devices to shield X-rays. Because of health concerns, lead from gasoline, paint and ceramic products, caulking and pipe solder has been dramatically reduced.
Health effects and symptoms:
Lead can affect almost every organ and system in your body, whether breathed or swallowed. The most sensitive is the central nervous system, especially in children. Even at low levels, lead poisoning has been linked to reduced growth, aggressive behavior and lower intellect in children. Lead also damages kidneys and the reproductive system. Lead can cause anemia, weakness in fingers, wrists or ankles, and damage the male reproductive system. It may possibly affect the memory.
Mercury
A naturally-occurring metal with several forms. The metallic mercury is a shiny, silver-white, odorless liquid. If heated, it is a colorless, odorless gas. Mercury combines with other elements, such as chlorine, to form inorganic compounds such as mercuric chloride. Mercury and its compounds may also combine with carbon to make organic mercury compounds, such as methylmercury.
Usage:
Metallic mercury is used to make chlorine gas and caustic soda, and is also used in thermometers, dental fillings and batteries.
Health effects and symptoms:
The nervous system is very sensitive to all forms of mercury. Methylmercury and metallic mercury vapors are more harmful than other forms because they reach the brain, potentially causing permanent brain damage or damage to the kidneys. Mercury poisoning can result in irritability, shyness, tremors, changes in vision or hearing and memory problems. Mercuric chloride and methylmercury are possible human carcinogens, according to the EPA. Mercury's harmful effects that can be passed from the mother to the fetus include brain damage, mental retardation, incoordination, blindness, seizures and inability to speak. Children poisoned by mercury may develop problems in the nervous and digestive systems and kidney damage.
