Octachlorodibenzodioxin

Octachlorodibenzodioxin (abbreviated as OCDD or OctaCDD) is one of polychlorinated dibenzodioxins (PCDDs). When compared to 2,3,7,8-tetrachlorodibenzodioxin (TCDD), its toxicity is about 3000 times weaker.^[1]

Octachlorodibenzodioxin

Skeletal formula
Ball-and-stick model
Names
Preferred IUPAC name Octachlorooxanthrene
Other names OCDD, Octachlorodibenzo-p-dioxin
Identifiers
CAS Number	3268-87-9 Y
3D model (JSmol)	Interactive image
ChemSpider	17598 N
ECHA InfoCard	100.223.031
PubChem CID	18636
UNII	YW59P10266 Y
CompTox Dashboard (EPA)	DTXSID4025799
SMILES ClC1=C2C(OC(C(Cl)=C(Cl)C(Cl)=C3Cl)=C3O2)=C(Cl)C(Cl)=C1Cl
Properties
Chemical formula	C12Cl8O2
Molar mass	459.73 g·mol−1
Related compounds
Related Polychlorinated dibenzodioxins	Tetrachlorodibenzodioxin
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

It is one of the dominant PCDD congeners in smoke emissions, but because it is much less soluble than TCDD, it is not bioaccumulated as effectively and it is toxicologically less important than the most prevalent dioxins. (For details see Dioxins and dioxin-like compounds).

Chlorinated pesticides can also contain impurities of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDD/Fs) and their precursors. "Precursor formation of PCDD/Fs can also be mediated by ultraviolet light (UV)" from sun (OCDD mostly). Changes in congeners ratio after UV exposition suggest that pesticide sources of dioxines-like after sunlight exposure "may not be recognized based on matching source fingerprints established from manufacturing impurities. These changes also provide preliminary insights into the possible formation routes and types of precursors involved".^[2]