Polychlorinated Biphenyls (PCBs)
What are they?
- Polychlorinated Biphenyls, also known as PCBs, are a group of synthetic chemicals that are similar in structure with different degrees of chlorination.
How are they used?
- PCBs were not manufactured in Canada, but were used in a wide range of industrial activities. PCBs were used as dielectrics in electrical transformers and capacitors, as heat exchange fluids, as paint additives or in plastics (in sealing and caulking compounds), cutting oils, and inks.
What are their effects?
- PCBs are very persistent both in the environment and in living tissue. The most obvious signs of environmental harm caused by PCBs are in aquatic ecosystems and in species that eat primarily aquatic organisms.
- Little is known about the health impacts that result from long-term exposure to low concentrations of PCBs. Most of what is known about the health risks of short-term exposure to PCBs is based on observations of people who were briefly exposed to high levels of PCBs as a result of accidents or job-related activities.
- Currently, the available scientific information demonstrates that exposure of experimental animals to PCBs can cause cancer in animals, however, there is not enough scientific information to determine the relationship between exposure to PCBs and the incidence of disease, such as cancer. The consensus among scientists around the world is that PCBs should be (and are) classified as probable human carcinogens.
What is the Government of Canada doing?
- Strong and effective action has been taken on PCBs under the Canadian Environmental Protection Act, 1999 (CEPA 1999) and other laws, since 1977. PCBs are specified on the List of Toxic Substances under CEPA 1999.
- On September 17, 2008, Environment Canada published the new PCB Regulations in the Canada Gazette Part II as a final publication. The manufacture, export, import, offer for sale, sale, use, processing, storage and release of PCBs continue to be controlled under this new legislation. These Regulations, in addition to strengthening controls, set deadlines for ending the use of PCBs, eliminating PCBs currently in storage and limiting the storage time period before PCBs are destroyed.
- On March 31, 2010, Environment Canada published amendments to the new PCB Regulations in the Canada Gazette Part II as a final publication. These amendments provide additional flexibility to the industry by allowing on-site destruction in accordance with provincial and territorial legislation. The amendments do not change deadlines for the destruction of PCBs or delay their elimination from use and storage in Canada.
- The PCB Regulations and amendments to these regulations may be found on the CEPA Environmental Registry Web Site.
- Exposure to the general population in Canada is expected to be low and Health Canada is continuing to monitor amounts of PCBs in food, air and water so that exposure remains low.
Being informed is the best protection. Find out more about PCBs from Health Canada's It's Your Health factsheet on PCBs , and Environment Canada's Web site on PCBs and on Management of Toxic Substances.
Health risks associated with a chemical depend on the hazard (its potential to cause health effects) and the dose (the amount of chemical to which you are exposed).