The Lab
Specimen No. 0184
AvoidSyntheticfood artificial dyes

Blue 2

Indigo Carmine · E132

Master DB rating: Avoid. Listed for: Candy, cereal, pet food

medium confidence
Researched July 7, 2026

Concerns

  • FDA's own pivotal chronic-feeding study found a statistically significant increase in brain gliomas among high-dose male rats, though FDA and the study authors concluded this was not biologically significant; a parallel mouse feeding study found no evidence of carcinogenicity (Borzelleca & Hogan 1985)
  • No human carcinogenicity data exist; the dye has not been independently retested with modern methods since the 1985 studies

Regulatory flags

  • IARC Class: NL
  • EDC Status: None
  • Regulatory: US: GRAS/certified (21 CFR 74.102); EU: permitted with limits
  • Evidence Grade: B

Commonly found in

Candy, cereal, pet food

Research disclaimer: This rating is based on available peer-reviewed research and regulatory assessments at the time of publication. It is not medical advice. Consult a qualified professional for personal health or skin concerns.

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