Polychlorinated dibenzodioxins
（重定向自Dioxine）
![The skeletal formula and substituent numbering scheme of the parent compound dibenzo-1,4-dioxin](/Images/godic/202501/09/Dibenzo-p-dioxin-numbering-2D-skeletal3334.png")
![Concentration profile of PCDD in a dated sediment core from Esthwaite Water, Cumbria, UK.](/Images/godic/202501/09/PCDD_sediment_core.svg3334.png")
![A chart illustrating how much dioxin the average American consumes per day. (Note: pg = picogram, or one trillionth of a gram, or 10−12 g) .[18]](/Images/godic/202501/09/Dioxin_chart3334.png")
![Space-filling model of 2,3,7,8-tetrachlorodibenzodioxin.](/Images/godic/202501/09/Dioxin-3D-vdW3334.png")
Polychlorinated dibenzodioxins (PCDDs), or simply dioxins, are a group of polyhalogenated organic compounds that are significant environmental pollutants.
They are commonly but inaccurately referred to as dioxins for simplicity, because every PCDD molecule contains a dibenzo-1,4-dioxin skeletal structure, with 1,4-dioxin as the central ring. Members of the PCDD family bioaccumulate in humans and wildlife because of their lipophilic properties, and may cause developmental disturbances and cancer.