Polychlorinated+biphenols

=**//Polychlorinated Biphenols//**= Polychlorinated Biphenols are synthetic (human-made) chemicals first produced in the late 1920s. They were used as cooling fluids in electrical equipment and machinery because of their durability and resistance to fire. These chemicals were banned in 1979 ==== **PCB Chemical formula**:C12H(10-x)Clx, where 'x' = the number of chlorine atoms. For example, if 4 chlorine atoms replaced 4 hydrogen atoms, the formula would be C12H6Cl4. the Biphenol is just 2 benzene rings put together. ====

(benzene ring) (Polychlorinated Biphenol)
**Products to avoid** are: (all products made prior to 1979 on this list)
 * transformers and capacitors
 * Voltage Regulators
 * Switches
 * Reclosers
 * Bushings
 * Electromagnets
 * motor and hydraulics oil
 * Flourescent Light Ballasts
 * Cable Insulation
 * Thermal Insulation Material
 * Adhesives and Tapes
 * Oil-based Paint
 * Caulking
 * Carbonless Copy Paper
 * Floor Finish

**Health Hazards**
Health Hazards associated with Polychlorinated Biphenols are**:**
 * Cancer
 * effects on the immune system
 * effects reproductive system
 * effects endocrine system
 * effects nervous system

**Immune Effects **
====The immune system is critical for fighting infections, and diseases of the immune system have very serious potential implications for the health of humans and animals. The immune effects of PCB exposure have been studied in Rhesus monkeys and other animals. It is important to note that the immune systems of Rhesus monkeys and humans are very similar. Studies in monkeys and other animals have revealed a number of serious effects on the immune system following exposures to PCBs, including a significant decrease in size of the thymus gland (which is critical to the immune system) in infant monkeys, reductions in the response of the immune system following a challenge with sheep red blood cells (a standard laboratory test that determines the ability of an animal to mount a primary antibody response and develop protective immunity), and decreased resistance to Epstein-Barr virus and other infections in PCB-exposed animals. Individuals with diseases of the immune system may be more susceptible to pneumonia and viral infections. The animal studies were not able to identify a level of PCB exposure that did not cause effects on the immune system. ==== In humans, a recent study found that individuals infected with Epstein-Barr virus had a greater association of increased exposures to PCBs with increasing risk of non-Hodgkins lymphoma than those who had no Epstein-Barr infection. This finding is consistent with increases in infection with Epstein Barr virus in animals exposed to PCBs. Since PCBs suppress the immune system and immune system suppression has been demonstrated as a risk factor for non-Hodgkin's lymphoma, suppression of the immune system is a possible mechanism for PCB-induced cancer. Immune effects were also noted in humans who experienced exposure to rice oil contaminated with PCBs, dibenzofurans and dioxins. Taken together, the studies in animals and humans suggest that PCBs may have serious potential effects on the immune systems of exposed individuals.

**Reproductive Effects **
====Reproductive effects of PCBs have been studied in a variety of animal species, including Rhesus monkeys, rats, mice and mink. Rhesus monkeys are generally regarded as the best laboratory species for predicting adverse reproductive effects in humans. Potentially serious effects on the reproductive system were seen in monkeys and a number of other animal species following exposures to PCB mixtures. Most significantly, PCB exposures were found to reduce the birth weight, conception rates and live birth rates of monkeys and other species and PCB exposure reduced sperm counts in rats. Effects in monkeys were long-lasting and were observed long after the dosing with PCBs occurred. ==== Studies of reproductive effects have also been carried out in human populations exposed to PCBs. Children born to women who worked with PCBs in factories showed decreased birth weight and a significant decrease in gestational age with increasing exposures to PCBs. Studies in fishing populations believed to have high exposures to PCBs also suggest similar decreases. This same effect was seen in multiple species of animals exposed to PCBs, and suggests that reproductive effects may be important in humans following exposures to PCBs.

**Neurological Effects **
====Proper development of the nervous system is critical for early learning and can have potentially significant implications for the health of individuals throughout their lifetimes. Effects of PCBs on nervous system development have been studied in monkeys and a variety of other animal species. Newborn monkeys exposed to PCBs showed persistent and significant deficits in neurological development, including visual recognition, short-term memory and learning. Some of these studies were conducted using the types of PCBs most commonly found in human breast milk. ==== Studies in humans have suggested effects similar to those observed in monkeys exposed to PCBs, including learning deficits and changes in activity associated with exposures to PCBs. The similarity in effects observed in humans and animals provide additional support for the potential neurobehavioral effects of PCBs.

**Endocrine Effects **
====There has been significant discussion and research on the effects of environmental contaminants on the endocrine system ("endocrine disruption"). While the significance of endocrine disruption as a widespread issue in humans and animals is a subject of ongoing study, PCBs have been demonstrated to exert effects on thyroid hormone levels in animals and humans. Thyroid hormone levels are critical for normal growth and development, and alterations in thyroid hormone levels may have significant implications. ==== It has been shown that PCBs decrease thyroid hormone levels in rodents, and that these decreases have resulted in developmental deficits in the animals, including deficits in hearing. PCB exposures have also been associated with changes in thyroid hormone levels in infants in studies conducted in the Netherlands and Japan. Additional research will be required to determine the significance of these effects in the human population. Effects taken from website: []

There has been efforts to erase this chemical. Perhaps the most widely known of organic contaminants, polychlorinated biphenyls (PCBs) are a serious environmental problem due to their wide-dispersal and extreme persistence in the environment. Used in a variety of industrial and commercial purposes, PCBs were readily manufactured from the 1930s until studies showing adverse environmental effects resulted in production bans by many countries. Today, regulations are in place governing the storage, distribution, use and disposal of PCBs. There was a ban on PCBs in 1979.  How am I exposed?We are still exposed to PCBs and DDT through our food. About PCBs: · How can I reduce my exposure?· Unless you live near an industrial or agricultural site contaminated with PCBs or DDT, your greatest source of exposure to these chemicals is likely to be food. While you cannot completely avoid these chemicals in your diet, you can make some choices that will help reduce your exposure to them.· The most important actions you can take to reduce the PCBs and DDT in your diet are to cut back on animal fats and watch the type of fish you eat.· Choose fish wisely. Check with state advisories before eating sport-caught fish or shellfish, which are often high in PCBs and DDT. Commercial fish that are high in PCBs include Atlantic or farmed salmon, bluefish, wild striped bass, white and Atlantic croaker, blackback or winter flounder, summer flounder, and blue crab. Commercial fish that contain higher levels of pesticides, including DDT, are bluefish, wild striped bass, American eel, and Atlantic salmon.· When preparing fish, remove the skin, trim the fat, and broil, bake, or grill the fish so that the fat drips away; this will reduce your exposure to PCBs and other toxic chemicals that have accumulated in fatty tissue. Fish are an excellent source of nutrients including protein, omega-3 fatty acids, and vitamin D, so don’t remove fish from your diet—but do be selective about the fish you eat.· Make your meat lean. When it comes to meat, choose lean meat cuts, and buy organic meats if possible. Cut off visible fat before cooking meat and choose lower-fat cooking methods: broiling, grilling, roasting or pressure-cooking. Avoid frying meat in lard, bacon grease, or butter.  <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> **__﻿__** [] <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> **__﻿__** [] <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> [] <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> [] <span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> []
 * Efforts to erase**
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l1 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">Animal and fatty foods contain the highest levels of DDT and PCBs because they are stored in fat and increase in concentration as they move up the food chain.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l1 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">Even though it was banned in 1972, vegetables, meat, fish, and dairy products contain DDT.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l1 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">PCBs and DDT build up in sediment in rivers, lakes, and coastal areas, then accumulate in fish.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l1 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">Women who consume PCBs in their diet pass them to their children in breast milk: infants may get 6 to 12% of their lifetime exposure to PCBs from breastfeeding.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l1 level1 lfo1; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">PCBs are a major contaminant in Puget Sound where they are found at very high levels in salmon and in endangered orca whales, among the most contaminated marine mammals in the world.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l0 level1 lfo2; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">PCBs can have profound effects on intellectual development. Children with greater exposure to PCBs have lower birth weights, slowed growth, and poorer performance on tests of brain development.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l0 level1 lfo2; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">PCBs cause tumors in laboratory animals. EPA lists PCBs as probable human carcinogens.
 * <span style="background: white; color: #333333; line-height: normal; margin: 0in 0in 10pt; mso-list: l0 level1 lfo2; mso-margin-bottom-alt: auto; mso-margin-top-alt: auto; tab-stops: list .5in;">Studies suggest that PCBs are also toxic to the immune system, reproductive organs, and thyroid.
 * __<span style="color: #404040; font-family: Arial,Helvetica,sans-serif; font-size: 80%;"> ﻿   References:__**