Polychlorinated Biphenyls (PCBs)
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
What are Polychlorinated biphenyls (PCBs)?
There are no known natural sources of PCBs in our environment. PCBs are either oily liquids or solids, are colorless to light yellow, and have no smell or taste. Because they do not easily burn and are good insulators, PCBs have been used widely as coolants and lubricants. PCBs are persisten, bioaccumulative and toxic (PBT) pollutants that have been targeted by EPA.
Why Are We Concerned About PCBs?
PCBs do not break down in our environment and can have severe health effects on humans. PCBs in the air eventually return to our land and water by settling or from runoff in snow and rain. In our water, PCBs build up in fish and can reach levels hundreds of thousand of times higher than the levels in water. Fish consumption advisories are in effect for PCBs in all five of the Great Lakes. PCBs are the leading chemical risk from fish consumption.
What harmful effects can PCBs have on us?
- Probable human carcinogen
- Damages the stomach
- Skin irritation
- Liver and Kidney damage
- Thyroid gland injuries
How are we exposed to PCBs?
- By eating contaminated fish and shellfish
- Infants may be exposed through breast milk
- Unborn children may exposed while in the womb
- May be in milk, meat, and their by-products
- Breathing indoor air in buildings where electrical equipment contains PCBs
Where can PCBs be found?
Manufacturing of PCBs stopping in the Unites States in 1977 because they were found to build up in our environment and cause harmful effects. However, we can still find them in our environment, especially in our lakes, rivers, and streams.
- Municipal and industrial incinerators from the burning of organic wastes
Potential Sources to our Environment:
- Poorly maintained hazardous waste sites containing PCBs
- Illegal/improper dumping of PCB wastes such as transformer fluids
- Leaks or releases from electrical transformers containing PCBs
- Improper disposal of PCB-containing consumer products
- Old microscope oil and hydraulic fluids
- Old T.V.'s and refrigerators, lighting fixtures, electrical devices, or appliances containing PCB capacitators made before 1977.
- Sediments in the bottom of lakes, river, or our ocean constantly release small amounts of PCBs into the environment.