Introduction    |    History    |    Legislation    |    Links & References

What are PCBs?

PCBs : Polychlorinated biphenyls. A class of organics produced by chlorination of a biphenyl.
Within this category there are many varieties of compound. However, when considering contamination, the four main categories studied are PCB liquids, PCB solids & PCB equipment. All three of these categories make up PCB waste.

What are the uses of PCBs?

PCBs were very popular in commercial & industrial circles. The uses for them were many and varied, but some examples of products they were used include :

• Electrical & heat conduction
• Flame retardants
• plastics
• rubber
• paints & dyes
• transformers (electricity)

What are the dangers of PCBs?

PCBs have been found to be both toxic and carcinogenic. That means that they have damaging affects on both organisms (including humans) and where they exist.

• Environmental Effects
  • Contamination : PCBs have been found in the atmosphere, soil, water, sediment, fish & wildlife.
  • Bioaccumulation : concentrations of these persistant chemicals are stored in organisms so their concentration increases greatly with every step in a food chain. Each upward level therefore has compounded problems.
  
  
• Health Effects
  • PCBs have been proven to cause cancer in animals. They are also probable causes of cancer within humans.
  • PCBs have been found to damage the immune system, the reproductive system, the neurological system & the endocrine system in both animals and humans.
  • Changes in the levels of PCBs within the blood system has been found to cause liver problems (due to filtration damage) & problems with the blood chemical levels themselves.

The amount of negative effects PCBs were having quickly came to outweigh the advantages of their uses.

Examples of PCB contaminations : The DEW Lines

Along with general information, this site contains information on a more specific example : The DEW Lines. These were part of the cold war warning system placed in Canada by the American government. When considering biomagnification, their presence and lack of further care allowed PCBs to contaminate the land around them. When considering legislation, these are even more of an issue due to the debate of which government should have the responsibility of caring for this contamination.

For more information about PCBs see :

     Introduction     |     History     |     Legislation     |     Links & References

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