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Dioxin at Superfund Sites

These dioxin pages provide information supporting the development of cleanup plans for dioxin at Superfund sites. 

Dioxins are a group of compounds that share distinct chemical structures and characteristics. The term dioxin commonly refers to the compound in this group considered most toxic, 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD). Dioxin-like is a description used for compounds that have chemical structures, physico-chemical properties, and toxic responses similar to TCDD. Dioxin-like compounds (DLCs), including polychlorinated dibenzo p dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs), are typically found in mixtures with TCDD at Superfund sites. For this website, two terms are used; either TCDD for the 2,3,7,8-tetrachlorodibenzo-para-dioxin compound, or the term dioxin for TCDD plus DLCs, i.e. dioxins, furans, and dioxin-like PCB compounds.

Additional dioxin information can be found at the EPA's dioxin web area: