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Testing Status of Toxic equivalency factor evaluation (Binary mixture; PCB 126/PCB 153) M960055



Formula: N/A

Synonyms/Common Names

  • Binary mixture (Toxic equivalency factor evaluation)
  • Toxic equivalency factor evaluation (Binary Mixture)


  • 35065-27-1 - 2,2'-4,4',5,5'-Hexachlorobiphenyl (PCB 153)
  • 57465-28-8 - 3,3,4,4,5-Pentachlorobiphenyl (PCB 126)
  • 57465-28-8 - TEF transgenics (PCB 126)
  • 35065-27-1 - Toxic equivalency factor evaluation (PCB 153- 2,2'-4,4',5,5'-hexachlorobiphenyl)
  • 57465-28-8 - Toxic equivalency factor evaluation ((PCB 126) 3,3',4,4',5-pentachlorobiphenyl)

Known Uses

Used in the electric industry as dielectric insulating fluids for transformers and capacitors. PCBs were also produced for use in hydraulic fluids, solvents, plastics, and paints. One of 2 mixtures being tested along with 5 dioxin-like compounds to determine if the toxic equivalency factors (TEFs) for these chemicals would be predictive of rodent carcinogenicity.

Long-Term Carcinogenicity

  • 2 years (Gavage)  (C96020)  Completed 
    • TR-530 (NIH Number: 06-4466)  (Peer Review Approval 12/09/2004A )
      Toxicology and Carcinogenesis Studies of a Binary Mixture of 3,3',4,4',5-Pentachlorobiphenyl (PCB 126) (CASRN 57465-28-8) and 2,2',4,4',5,5'-Hexachlorobiphenyl (PCB 153) (CASRN 35065-27-1) in Female Harlan Sprague-Dawley Rats (Gavage Studies)
    • Rats: Harlan Sprague-Dawley
    • Carcinogenesis Results
      • Female Rats Clear Evidence 
    • Dose: Female rats only: 0; (PCB126) 10, 100, 300, or 1000 ng/kg; (PCB 153) 10, 100, 300, or 1000 ug/kg; 50/dose.