PCB Polychlorinated biphenyl. What are PCBs? PCBs belong to a broad family of man-made organic...

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PCB• Polychlorinated biphenyl

What are PCBs?• PCBs belong to a broad

family of man-made organic chemicals known as chlorinated hydrocarbons. PCBs were domestically manufactured from 1929 until their manufacture was banned in 1979. They have a range of toxicity and vary in consistency from thin, light-colored liquids to yellow or black waxy solids.

Physical and chemical properties• Less-chlorinated PCBs are odorless, tasteless, clear to pale-

yellow, viscous liquids, while highly chlorinated mixtures are more viscous and deeper yellow.

• PCBs have low water solubility and low vapor pressures at room temperature, but they have high solubilitiy in most organic solvents, oils, and fats.

• PCBs are very stable compounds and do not decompose readily.

Sources• Illegal landfills,• Fires of PCBs contained devices,• Pouring out used oils directly to the ground,• Leaks from capacitors and transformers.

Uses for polychlorinated biphenyls• Polychlorinated biphenyls

were formerly used in the United States as hydraulic fluids, plasticizers, adhesives, fire retardants, way extenders, de-dusting agents, pesticide extenders, inks, lubricants, cutting oils, in heat transfer systems, carbonless reproducing paper.

Which parts of body are affected by PCBs?• Once absorbed, PCBs move into cell membranes and into the

blood vessels and the lymphatic system. The highest concentrations of PCBs are usually found in the liver, fatty tissue, brain, and skin. They are also present in the blood. In mothers, PCBs have been found to pass into umbilical cord blood, the placenta and breast milk.

What are PCBs effects on human health?• Some people who have drunk water containing PCBs well in

excess of the maximum contaminant level for many years could experience changes in their skin, problems with their thymus gland, immune deficiencies, or reproductive or nervous system difficulties, and may have an increased risk of developing cancer.

What are PCBs effects on human health?• Women who were

exposed to relatively high levels of PCBs had babies that weighed slightly less than babies of women who did not have these exposures. It also causes abnormal responses in tests of infant behavior. Some of these behaviors, such as problems with motor skills and a decrease in short-term memory, lasted for several years

What are PCBs effects on animal health?• Animals that eat PCB-

contaminated food even for short periods of time suffer from liver damage and may die. Animals that ingest smaller amounts of PCBs in food over several weeks or months develop various health effects, including anemia; acne-like skin conditions; and liver, stomach, and thyroid gland injuries. Other effects of PCBs in animals include changes in the immune system, behavioral alterations, and impaired reproduction.

Thank you for your attention

• Zuzia Ruszkowska• Kasia Szostek• Agnieszka Senderowska• Julia Napiórkowska