Where do dioxins and furans come from?
Dioxins and furans are chemical compounds that contain chlorine and can occur in 210 different configurations, called congeners. Dioxins and furans do not have a known use. They are produced unintentionally by human activities, including waste incineration, chemical manufacturing, petroleum refining, fuel combustion in vehicles, wood burning, and electric power generation. In the past, pulp and paper mill effluents were a major source of dioxins and furans, but regulations that came into effect in 1992 significantly reduced this source. Dioxins and furans are also produced by natural events such as forest fires and volcanic eruptions. In 1997, nearly half of the dioxin and furan load to Canada’s environment was produced by releases to the atmosphere from combustion sources. Atmospheric transport can occur over long distances, taking dioxins and furans far from their original source. Dioxins and furans are considered toxic under the Canadian Environmental Protection Act, and federal tox
