Pet Safety / Compounds / Iron oxide (Fe3O4, FeO, Fe2O3)

Is Iron oxide (Fe3O4, FeO, Fe2O3) safe for dogs and cats?

Elevated risk for pets

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

What is iron oxide (fe3o4, feo, fe2o3)?

The IUPAC name is oxo(oxochromiooxy)chromium.

Also known as: oxo(oxochromiooxy)chromium, Chromium(III) oxide, Chromia, Dichromium trioxide.

IUPAC name
oxo(oxochromiooxy)chromium
CAS number
1308-38-9
Molecular formula
Cr2O3
Molecular weight
151.99 g/mol
SMILES
O=[Cr]O[Cr]=O
PubChem CID
517277

Risk for dogs

Elevated risk

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

Risk for cats

Elevated risk

GHS Danger classification. Cats lack metabolic pathways to detoxify many synthetic chemicals.

Regulatory consensus

2 regulatory and scientific bodies have classified Iron oxide (Fe3O4, FeO, Fe2O3). The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA CTX / Genetox—Genotoxicity: negative (Ames: negative, 0 positive / 10 negative reports)
EPA CTX / Genetox—Genotoxicity: negative (Ames: negative, 0 positive / 10 negative reports)

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where pets encounter iron oxide (fe3o4, feo, fe2o3)

  • Contaminated Water — Mining site runoff, Industrial discharge, Old infrastructure
  • Food Chain — Fish from contaminated waters, Crops in contaminated soil
  • Consumer Products — food products, candy, beverages, cosmetics, supplements

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Iron oxide (Fe3O4, FeO, Fe2O3):

  • Natural dyes (indigo, madder, weld) where applicable
    Trade-offs: Lower colorfastness. Limited palette. Higher cost per unit.
    Relative cost: 2-5× conventional
  • Reactive dyes with lower aquatic toxicity
    Trade-offs: Not suitable for all fiber types
    Relative cost: 1.2-2×

Frequently asked questions

Is iron oxide (fe3o4, feo, fe2o3) safe for pets?

GHS Danger classification. Dogs lack metabolic pathways to detoxify many synthetic chemicals.

What products contain iron oxide (fe3o4, feo, fe2o3)?

Iron oxide (Fe3O4, FeO, Fe2O3) appears in: Mining site runoff (Contaminated water); Industrial discharge (Contaminated water); Fish from contaminated waters (Food chain); Crops in contaminated soil (Food chain); food products (Consumer products).

See Iron oxide (Fe3O4, FeO, Fe2O3) in the pets app

Look up products containing iron oxide (fe3o4, feo, fe2o3), compare to alternatives, and explore the full data record.

Open in pets View raw API data

Sources (3)
  1. PubChem Compound CID 517277 — database
  2. EPA CompTox Chemicals Dashboard — DTXSID4043721 — epa
  3. ATSDR Toxicological Profile — CAS 1308-38-9 — reference

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →