Polychlorinated biphenyls (PCBs)

Polychlorinated biphenyls (PCBs) are toxic, persistent manmade chemicals that were widely used as an oil additive in electrical equipment and as a plasticizer in building materials. Congress banned the manufacture and use of PCBs in 1978. 

Before their manufacture was banned, PCBs were used widely in electrical equipment, including transformers. Many transformers in use still contain traces of PCB-contaminated oil, even after the oil has been changed several times. It should be assumed that any oil-filled electrical equipment that ever contained PCBs will be regulated. If you are planning a remodel, laboratory move or standard maintenance and alterations, you must have equipment suspected or known to contain PCBs inspected and screened.

Fluorescent light ballasts may contain PCBs and must be managed through EH&S. All ballasts manufactured through 1978 contain PCBs. Newer ballasts may still contain PCBs or the carcinogenic chemical DEHP. For these reasons, all fluorescent light ballasts which are not specifically labeled "No PCBs" are to be managed as dangerous waste.  

Leaking PCB ballasts are considered an occupational exposure hazard by skin contact.

  • If the contamination is extensive, call the EH&S Spills Advice line at 206.543.0467.
  • Call 911 if there is an explosion, fire, serious injury or catastrophic leak.

Buildings constructed or renovated between 1950 and the 1970s may have PCBs in the caulk around windows, in weather stripping and in masonry expansion joints. These materials have tested positive for PCBs on UW campuses and in buildings around the nation.

Common building materials that may contain PCBs

Buildings and structures built or renovated between 1929 and 1979 may contain PCBs, particularly:

  • Door and window caulking
  • Paint
  • Galbestos roofing and siding
  • Fluorescent light ballasts
  • Various forms of joint material

image shows common building materials that contain PCBs
Source: Washington State Department of Ecology


How PCBs in building materials affect people and the environment

  • Precipitation and pressure washing can pollute stormwater with PCBs from building materials, surface soils, and air.
  • Construction debris that is disturbed may release PCBs.
  • PCBs in air can circulate, contaminate other materials, and affect indoor air quality.
  • PCBs in stormwater can contaminate surface water, sediment, and aquatic life. 

image shows how PCBs affect people and environment
Source: Washington State Department of Ecology

Services available

EH&S oversees PCB management, coordinates sampling and disposal, conducts audits, reviews work plans and ensures compliance with regulations.

Guidelines for proper cleanup and disposal of PCBs can be found in the EH&S Hazardous Material Design Guides.

EH&S can provide assistance with identifying, managing, and disposing of PCB contaminated waste.