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Testing Status of Toxic equivalency factor evaluation (TCDD) M960049


CASRN: 1746-01-6

Formula: C12-H4-Cl4-O2

Synonyms/Common Names

  • TCDD (Toxic equivalency factor evaluation)
  • Toxic equivalency factor evaluation (TCDD)
  • Toxic equivalency factor evaluation (2,3,7,8-Tetrachlorodibenzo-p-dioxin)

Known Uses

TCDD is not manufactured commercially other than for scientific research purposes. One of 5 dioxin-like compounds plus 2 mixtures being tested to determine if the toxic equivalency factors (TEFs) for these chemicals would be predictive of rodent carcinogenicity.

Chemical Properties

Toxicity Effects (HSDB)

Long-Term Carcinogenicity

  • 2 years (Gavage)  (C96007G)  Completed 
    • TR-521 (NIH Number: 06-4468)  (Peer Review Approval 02/17/2004A )
      Toxicology and Carcinogenesis Studies of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) (CASRN 1746-01-6) in Female Harlan Sprague-Dawley Rats (Gavage Studies)
    • Rats: Harlan Sprague-Dawley
    • Carcinogenesis Results
      • Female Rats Clear Evidence 
    • Dose: FEMALE RATS ONLY: TCDD -- 0, 3, 10, 22, 46, OR 100 NG/KG; 100/DOSE.