National Toxicology Program

CASRN: TEFPCBMIX

Synonyms/Common Names:

• PCB MIXTURE (TOXIC EQUIVALENCY FACTOR EVALUATION)
• TOXIC EQUIVALENCY FACTOR EVALUATION (PCB MIXTURE (PCB 126/PCB 118))

Secondary:

• 31508-00-6 - 2,3',4,4',5-Pentachlorobiphenyl
• 57465-28-8 - 3,3,4,4,5-Pentachlorobiphenyl (PCB 126)
• 31508-00-6 - TEF evaluation (PCB 118)
• 57465-28-8 - TEF transgenics (PCB 126)
• 57465-28-8 - Toxic equivalency factor evaluation ((PCB 126) 3,3',4,4',5-pentachlorobiphenyl)

Known Uses:

One of 2 dioxin-like compounds plus mixtures being tested to determine if the TEFs for these chemicals would be predictive of rodent carcinogenicity. This mixture consists of PCB 118 (2,3',4,4',5- pentachlorobiphenyl) & PCB 126 (3,3',4,4',5- pentachlorobiphenyl) Mixtures were produced commercially before 1977 for the electric industry as dielectric insulating fluids for transformers & capacitors

Long-Term Carcinogenicity

• 2-YEAR (Gavage)  (C96022)  Report Complete 
  • TR-531 (NIH Number: 07-4467; NTIS Number: PB2007-103748)  (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 2,3',4,4',5-Pentachlorobiphenyl (PCB 118) (CASRN 31508-00-6) in Female Harlan Sprague-Dawley Rats (Gavage Studies)
  • Rats: Harlan Sprague-Dawley
  • Carcinogenesis Results
  • Female Rats Clear Evidence 
  • Dose: FEMALE RATS ONLY (PCB 118/PCB 126): 0, 7, 22, 72, 216, OR 360 NG/KG; 50/DOSE.