National Toxicology Program

National Toxicology Program

Testing Status of 2,7-Dichlorodibenzo-p-dioxin - 10789-V


CASRN: 33857-26-0

Formula: C12-H6-Cl2-O2

Synonyms/Common Names

  • DCDD
  • 2,7-Dichlorodibenzo-p-dioxin

Known Uses

By-product in manufacture of a germicide and herbicide

Chemical Properties

Toxicity Effects (HSDB)

Short-Term Toxicity

  • 2 weeks (Dosed-Feed)  (C03667B)  Completed 
    • Rats: Osborne Mendel; Mice: B6C3F1
  • 13 weeks (Dosed-Feed)  (C03667B)  Completed 
    • Rats: Osborne Mendel; Mice: B6C3F1

Long-Term Carcinogenicity

  • 2 years (Dosed-Feed)  (C03667B)  Report Complete 
    • TR-123 (NIH Number: 79-1378)  (Peer Review Approval 01/00/1977A )
      Bioassay of 2,7-Dichlorodibenzo-p-dioxin (DCDD) for Possible Carcinogenicity (CASRN 33857-26-0)
    • Rats: Osborne Mendel; Mice: B6C3F1
    • Carcinogenesis Results
      • Male Rats Negative 
      • Female Rats Negative 
      • Male Mice Equivocal 
      • Female Mice Negative 
    • Dose: 0, 5000, 10000 PPM/35R - 50M PER GROUP.

Genetic Toxicology

  • Salmonella  (061158)  Completed 
    • Citation: Mortelmans, K., Haworth, S., Speck, W., and Zeiger, E. Mutagenicity testing of Agent Orange components and related chemicals Toxicology and Applied Pharmacology Vol. 75 (1984) 137-146
    •  Negative 
NTP is located at the National Institute of Environmental Health Sciences, part of the National Institutes of Health.