PCBs are now banned in the U.S. but can be found in old electrical equipment.
What are polychlorinated biphenyls (PCBs)?
Polychlorinated biphenyls, commonly called PCBs, are mixtures of up to 209 chlorinated compounds that do not occur naturally. PCBs are either oily liquids or waxy solids that are colorless to light yellow. They have no taste or smell. PCBs are persistent organic pollutants (POPs) and endocrine disruptors.
U.S. production of PCBs stopped in 1977 because of suspected harmful health and environmental effects; exports and imports of PCBs stopped in 1979. Before 1977, PCBs were used as insulation, coolants, and lubricants in transformers, capacitors, vacuum pumps, gas-transmission turbines, hydraulic fluids, and other electrical equipment; as fillers in casting waxes; as plasticizers in paints, plastics, and rubber products; and in surface coatings, sealants, caulking compounds, fire retardants, dedusting agents, glues, inks, pesticides, and carbonless copy paper. Products made before 1977 that may still contain PCBs include old fluorescent lights, electrical devices, and microscope hydraulic oils.How might I be exposed to PCBs?
You can be exposed to PCBs by breathing air that contains them, swallowing contaminated food or water, or touching products that contain them. How can PCBs affect my health?
Exposure to PCBs that entered the air, water, and soil during their use can occur because they remain in the environment for very long periods of time. You can be exposed to PCBs by using or being near older equipment and products that still contain PCBs, including electrical transformers, capacitors, fluorescent lighting fixtures, and appliances. You can also be exposed by eating contaminated fish, particularly sportfish from lakes and rivers, and game animals which have fed on smaller species in which PCBs have accumulated.
You can be exposed to PCBs by breathing air from hazardous waste sites, illegal or improper disposal of industrial wastes and consumer products, some incinerators, and leaks or fires in electrical transformers and other products containing PCBs; and by drinking well water that is contaminated with PCBs.
At work, you can be exposed to PCBs during the repair and maintenance of transformers that contain PCBs; from accidents, fires, or spills involving PCB transformers and older electrical equipment; and through the disposal of PCB materials. Exposure at work can occur if you work at a hazardous waste site where PCBs have been deposited and remain in the soil; or if you work in electric cable repair, electroplating, emergency response, firefighting, heat exchanging equipment repair, metal finishing, paving, roofing, pipefitting, plumbing, timber product manufacturing, and waste oil processing.
Swallowing large amounts of PCBs can cause coma and death.
PCBs are listed as "reasonably anticipated to be human carcinogens" in the Fourteenth Report on Carcinogens published by the National Toxicology Program because there is limited evidence of a relationship between exposure to PCBs and cancer in humans.
Long-term exposure to PCBs may have serious effects on the liver, immune system, endocrine system, reproductive system, and thyroid hormone levels, which in turn may affect normal growth and development. Exposure may damage the nervous system, causing headaches, numbness, weakness, and tingling in the arms and legs; it may also cause learning deficits and changes in activity.
If you are pregnant, exposure to PCBs can cause miscarriage or decreased birth weight in babies. Babies born to and nursed by women exposed to PCBs can have abnormal responses in tests of infant behavior, such as trouble with motor skills and short-term memory loss; immune system problems; and developmental abnormalities.
Short-term exposure to PCBs can irritate and burn the eyes, lungs, nose, and throat. It can cause coughing, difficulty breathing, nausea, vomiting, weight loss, depression, fatigue, sweating at the palms, jaundice, headache, dizziness, nervousness, muscle and joint pain, discoloration of fingernails, arthritis, and stomach pain. In women, short-term exposure can cause irregular menstrual cycles.
Skin contact with PCBs may cause an acne-like skin rash, which can last for years.
Nursing infants, fetuses, and people with liver disorders and skin diseases are most susceptible to the human health effects of PCBs. Drinking alcohol can increase the liver damage caused by PCBs.
If you think your health has been affected by exposure to PCBs, contact your health care professional.
For poisoning emergencies or questions about possible poisons, please contact your local poison control center at 1-800-222-1222.
This description is based on the information found in the Web links listed with this topic.
Map of Releases of Polychlorinated Biphenyls in the United States. TOXMAP (National Library of Medicine)
Polychlorinated Biphenyls (PCBs) (Arochlors) (Environmental Protection Agency) (PDF — 84.77 KB)
Polychlorinated Biphenyls. Hazardous Substances Data Bank (National Library of Medicine)
Polychlorinated Biphenyls. ToxFAQs (Agency for Toxic Substances and Disease Registry)
Preventing Exposure to PCB in Caulking Material (Environmental Protection Agency) (PDF — 291.97 KB)
What are PCBs? (Navy and Marine Corps Public Health Center) (PDF — 150 KB)
Last Updated: November 21, 2016