About
What it is and where it shows up.
Iron oxide red (Fe₂O₃) is a synthetic inorganic pigment belonging to the E172 family of iron oxides and hydroxides, which also includes yellow (E172i) and black (E172iii) forms. It is used as a red-to-brown colouring agent in foods, pharmaceuticals, and cosmetics, imparting colour to confectionery coatings, olives, and decorative cake surfaces.
Safety summary
The regulatory and scientific consensus.
A JECFA ADI of 0–0.5 mg/kg bw/day was established in 1980. Absorption of iron from iron oxides is low and acute oral toxicity is very high (>10 g/kg bw). However, EFSA's 2015 re-evaluation concluded that an adequate safety assessment could not be completed due to an insufficient toxicological database, with red and black iron oxide showing positive results in in vitro genotoxicity assays; EFSA recommended submission of additional toxicological data.
Regulatory landscape
What food-safety regulators have decided.
| Jurisdiction | Status | Note |
|---|---|---|
| FDA (Food and Drug Administration) (United States) | Restricted | Synthetic iron oxide is approved for specific uses in animal food under 21 CFR 73.200. Not broadly approved as a colour additive in human food in the US; use in drug products (e.g. capsule coatings) is separately regulated. Any colour additive use in US food must be authorized by 21 CFR Parts 73, 74, or 82.source |
| FSANZ (Food Standards Australia New Zealand) (Australia) | Approved | Iron oxides and hydroxides (INS 172) are recognised as permitted food additives under the Australia New Zealand Food Standards Code Standard 1.3.1, as referenced in EFSA's 2015 opinion on E172.source |
| EFSA (European Food Safety Authority) (European Union) | Approved | Authorised under Regulation (EC) No 1333/2008 for use in specific food categories (e.g. olive coatings, decorative food surfaces). JECFA ADI of 0–0.5 mg/kg bw/day applies. EFSA 2015 re-evaluation flagged insufficient toxicological data and called for additional studies; the EU has issued a formal call for data (call now closed) under Commission Regulation (EU) No 257/2010. Nickel impurity in E172 specifications (up to 200 mg/kg) flagged as a concern requiring revision.source |
| FSSAI (Food Safety and Standards Authority of India) (India) | Approved | Iron oxides (INS 172) are listed as permitted food additives under the Food Safety and Standards (Food Products Standards and Food Additives) Regulations, 2011. Specific food category permissions and maximum use levels are governed by Appendix A of those regulations. |
Who should approach with care
Whose guidance would steer them away.
Infants — EFSA exposure modelling shows toddlers reach up to 9.5 mg/kg bw/day at the 95th percentile — well above the JECFA ADI of 0.5 mg/kg bw/day — making this age group particularly vulnerable to excessive exposure relative to body weight.
Children — Refined EFSA exposure estimates indicate children (including toddlers) have the highest relative exposures to E172 across all age groups, potentially exceeding the established JECFA ADI at high consumption scenarios.
Ibd — Published research on nanoparticulate iron oxide (E172) highlights potential gastrotoxicity and impact on intestinal cells during digestion, which may be of particular concern for individuals with inflammatory bowel disease who have compromised gut barriers.
Liver Disease — Studies on nanoparticulate E172 analogs suggest potential hepatotoxicity and organ accumulation, and individuals with pre-existing liver disease may have impaired capacity to handle excess iron deposition.
Research citations
The sources behind this verdict.
- 1PubMed. Particulate iron oxide food colorants (E 172) during artificial digestion and their uptake and impact on intestinal cells, 2024. pubmed.ncbi.nlm.nih.gov
- 2PubMed. Food additives containing nanoparticles induce gastrotoxicity, hepatotoxicity and alterations in animal behavior: The unknown role of oxidative stress, 2020. pubmed.ncbi.nlm.nih.gov
- 3other. Call for scientific and technical data on the permitted food additives iron oxides and hydroxides (E 172) — European Commission DG SANTE, 2016. food.ec.europa.eu
- 4EFSA. Scientific opinion on the safety and efficacy of iron oxide black, red and yellow for all animal species, 2016. efsa.europa.eu
- 5EFSA. Scientific Opinion on the re-evaluation of iron oxides and hydroxides (E 172) as food additives, 2015. efsa.europa.eu
Independently researched5 citations