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PCBs are not highly toxic with a single dose (as in a single meal), but continued low levels of exposure (for example, eating contaminated fish over an extended period of time) may be harmful. What are the health risks associated with consuming PCB-contaminated fish?Īccording to EPA, contaminated fish are a persistent source of PCBs in the human diet. Three states (Indiana, Maryland and New York) and the District of Columbia have issued statewide freshwater advisories, and seven states (Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York and Rhode Island) have issued statewide coastal advisories for PCBs.Statewide advisories urge people to limit their consumption of all fish and shellfish from freshwater or coastal areas.
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As of 2003, more than two million lake acres and 130,000 river miles were covered by some type of PCB advisory. Thirty-nine states issued PCB advisories in 2003, up from 31 states in 1993. According to the Environmental Protection Agency's National Listing of Fish and Wildlife Advisories, advisories for PCBs increased 177% between 19 (from 319 to 884). Here they can enter the food chain and bioaccumulate in invertebrates, fish, birds and mammals - including people.Īlthough these chemicals have been banned for many years, increased testing has recently shown that the problem of PCB-contaminated fish is widespread.
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Most PCBs do not mix with water and settle into riverbeds, lake bottoms and coastal sediments. Unfortunately, the same properties that made PCBs ideal for industrial use make them slow to break down in the environment. More than 1.5 billion pounds of PCBs were manufactured in the United States before they were banned, and some electrical equipment in use today still contains PCBs. This combination of useful chemical properties made PCBs popular for a variety of industrial applications, including use in electrical transformers, hydraulic fluids, lubricants and carbonless paper. These mixtures tend to be chemically stable and nonflammable, with high boiling points and electrical insulating properties. There are 209 different PCB compounds (called congeners), which can be mixed in different combinations to yield different Aroclor compounds. PCBs are man-made chlorinated industrial chemicals also known by the trade name of Aroclor. What are PCBs and where do they come from? Based on available data on PCB concentrations in fish, Environmental Defense recommends limiting consumption of certain fish (see Health Alerts). These chemicals can build up in the fatty tissues of fish and other animals, and in high concentrations pose serious health risks to people who frequently eat contaminated fish. PCBs accumulate in the sediments at the bottoms of streams, rivers, lakes and coastal areas. Although they were banned from manufacture in the United States in 1977, PCBs are slow to break down and can persist in the environment at dangerous levels. These chemicals are harmful to adults as well. They pose serious health risks to fetuses, babies and children, who may suffer developmental and neurological problems from prolonged or repeated exposure to small amounts of PCBs. PCBs, or polychlorinated biphenyls, are highly toxic industrial compounds.