PCB's are organic chlorine compounds that are often used as insulator's in electrical equipment such as wiring, capacitors and transformers. The use of PCB's was prohitbited in 1975 and the storage, handling and disposal of PCB's is both provincially and federally regulated.

PCB's are likely carcinogenic to humans and can cause a wide range of adverse health effects, such as liver damage, respiratory disorders, skin discolouration, thyroid gland disorders and reproductive problems.