Non-Dioxin-Like Polychlorinated Biphenyls (PCBs)

Non-dioxin-like polychlorinated biphenyls (PCBs) are no longer produced in the United States, but they can still be found in the environment. PCBs are either solids or oily liquids that are colorless to light yellow. PCBs also can exist as vapor in air. PCBs were used as coolants and lubricants in transformers, capacitors, and other electrical equipment because they do not burn easily and are good insulators. In 1977, the United States stopped the manufacture of PCBs because of evidence that they built up in the environment and could harm health.

People can be exposed to PCBs by:

• Eating foods contaminated with PCBs. Dietary sources such as fish, meat, and dairy products are the main sources of exposure for the general public.
• Using old fluorescent lighting fixtures and electrical devices and some appliances made 30 or more years ago. These items may leak small amounts of PCBs into the air when they get hot during operation and could be a source of exposure.
• Breathing air from buildings built from 1950 to 1979 that could contain sealant caulk that contain PCBs.
• Being present during repair and maintenance of PCB transformers by electrical and maintenance workers.
• Being nearby during accidents, fires, or spills involving transformers, fluorescent lights, and other old electrical devices.
• Breathing air near hazardous waste sites and rarely, drinking well water contaminated with PCBs.

People exposed to high levels of PCBs in the workplace or after large accidental exposures may have skin conditions, such as acne or rashes. Studies in workers exposed to high levels of PCBs have shown changes in blood and urine that may indicate liver damage. Low level PCB exposures in the general population are not likely affect the skin and liver.

Infants can be exposed to PCBs from the mother’s blood before they are born and from breast milk that contains PCBs. Some, but not all, studies have shown an link between infant exposure to PCBs and lower scores on specific types of developmental tests. These studies also show that these subtle effects may disappear with time.

The U.S. Environmental Protection Agency and the International Agency for Research on Cancer have classified some PCBs as likely to cause cancer in humans. PCBs have been linked with other possible health effects including effects on the immune, reproductive, nervous, and endocrine systems.

More Information

Learn more about Polychlorinated Biphenyls (PCBs).