"Dioxins" refers to a group of chlorinated organic chemicals with similar
chemical structures.
In all GreenFacts publications the term "dioxins" is used to cover both
polychlorinated dibenzo-dioxins (PCDDs) and polychlorinated
dibenzo-furans (PCDFs). Other sources may refer to these
compounds as "dioxins and furans".
Some dioxins have harmful properties, depending on the number and position of
chlorine atoms. One of the most toxic dioxin is known as TCDD (2,3,7,8
tetrachlorodibenzo-p-dioxin). Some PCBs which have similar properties are
considered "dioxin-like".
Source: GreenFacts
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Dioxins have no uses. They are formed unintentionally and released as
byproducts of human activities such as waste incineration, fuels combustion,
chlorine bleaching of pulp and paper, or pesticide manufacturing. They are also
formed by natural processes such as forest fires and volcanoes.