Iron Oxides and Hydroxides E172
inorganic — Primarily mineral/metallic.
Iron oxides and iron hydroxides
CAS: 1309-37-1, 1332-37-2, 51274-00-1
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
What Is Iron Oxides and Hydroxides?
Iron oxides and hydroxides (E172) are inorganic pigments occurring naturally as minerals — yellow ochre (goethite), red ochre (hematite), and black iron oxide (magnetite) — and produced commercially through controlled chemical processes. They provide yellow, red, orange, brown, and black colors and are used in food applications including the coloring of olive oil, salmon and trout flesh in aquaculture feed, decorative cake coatings, and certain confectionery products. Iron oxides are generally considered inert and non-bioavailable when used as surface colorants, but considerations differ for internally consumed food applications. EFSA re-evaluated iron oxides and hydroxides in 2015 and established an ADI of 0.5 mg/kg body weight per day for food uses. They are approved in the EU and have limited FDA approval in the USA.
? Did You Know?
Iron Oxides and Hydroxides occurs naturally in Hematite (Fe2O3) - red iron ore and Magnetite (Fe3O4) - black iron ore. Many people consume it daily without realizing it's also a listed food additive.
Beyond food, Iron Oxides and Hydroxides is also used in cosmetics, medicine, industrial applications. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.
In the EU, Iron Oxides and Hydroxides has a "quantum satis" authorization — Latin for "as much as needed." This means there's no specific maximum limit; manufacturers use only what's technologically necessary.
Detailed Regulatory Assessment
European Union (EFSA)
Approved for use in various food categories. Not permitted in foods where coloring is prohibited.
Official EFSA LinkUnited States (FDA)
Not to exceed 0.1% by weight in sausage casings
Japan (MHLW)
Compliant with Japanese food sanitation law.
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Natural Occurrence
Naturally occurring minerals found abundantly in iron ore deposits. The different colors (red, yellow, black, brown) depend on the oxidation state and hydration of the iron.
Manufacturing
Food-grade iron oxides are typically produced synthetically through controlled oxidation of iron salts or by calcination of iron compounds. The production process ensures particle size, purity, and specific color (red, yellow, or black).
Applications Beyond Food
Widely used in makeup, lipstick, eye shadow, and foundation as a colorant. One of the safest colorants for cosmetics.
Used as a colorant in tablets and capsules. Also used in iron supplements.
Used in paints, pigments, ceramics, construction materials, and magnetic recording media.