The synthetic food colouring agent Allura Red AC (E129) is not genotoxic in a flow cytometry-based micronucleus assay in vivo

Food Chem Toxicol. 2013 Sep;59:86-9. doi: 10.1016/j.fct.2013.05.047. Epub 2013 Jun 6.


The safety of several azo colouring agents, used as food additives, has during the years been questioned. Allura Red AC (E129) has in some publications been classified as genotoxic. In fact, in the European Union, Allura Red is permitted as a food additive in human food, but, surprisingly, it was not acceptable as an additive for use in animal feed. In this study we have evaluated whether Allura Red is genotoxic using a flow cytometer-based micronucleus assay in peripheral blood of mice. Male FVB mice were given a single intra-peritoneal injection of various doses of Allura Red and sacrificed at 46 h after treatment. The tested doses were 0, 100, 200, 400, 600, 800, 1000, 1500, and 2000 mg/kg body weight (b.w.). Each dose group constituted three mice, except for in the dose group of 1000 mg/kg b. w., which constituted four mice. Blood samples were collected and the frequency of micronucleated polychromatic erythrocytes (fMNPCE) and the cell proliferation (%PCE) was determined. The analyses did not show any significant difference in the %PCE or in the fMNPCE. Consequently, under the testing circumstances one can conclude that Allura Red is not genotoxic.

Keywords: Allura Red; Azo dyes; Chromosome aberration; E129; Micronucleus test.

MeSH terms

  • Animals
  • Azo Compounds / administration & dosage
  • Azo Compounds / adverse effects*
  • Azo Compounds / pharmacokinetics
  • Cell Nucleus / drug effects
  • Cell Proliferation / drug effects
  • Dose-Response Relationship, Drug
  • Erythrocytes / cytology
  • Erythrocytes / drug effects*
  • Flow Cytometry
  • Food Coloring Agents / administration & dosage
  • Food Coloring Agents / adverse effects*
  • Food Coloring Agents / pharmacokinetics
  • Injections, Intraperitoneal
  • Male
  • Mice
  • Mice, Inbred Strains
  • Micronucleus Tests
  • Random Allocation
  • Reproducibility of Results
  • Tissue Distribution


  • Azo Compounds
  • Food Coloring Agents
  • Allura Red AC Dye