Polychlorinated biphenyls (PCBs) are synthetic compounds valued for their stability, making them ideal for electrical components until their use was restricted in the 1970s. While never manufactured in Canada, they were widely used here. PCB production and sale have been banned in Canada since 1977, though some PCB-containing equipment remains in use. PCBs persist in the environment and living tissue, are likely human carcinogens, and can produce highly toxic dioxins and furans when burned. To protect health and the environment, the federal PCB Regulations were enacted.