Ingredient review
Black Iron Oxide
INCI: CI 27755
A safe, widely used black pigment that adds color to makeup and skincare without active skincare benefits.
In plain English
Black iron oxide is a mineral pigment that gives a black color to cosmetics. It's made from iron and oxygen, the same elements that cause rust, but processed into a fine, stable powder. You'll find it in foundations, eyeliners, mascaras, and other color cosmetics. It doesn't treat skin or provide any skincare benefits—it's purely for color. The FDA and other global regulators consider it safe for use in cosmetics when used as intended.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is relatively strong for its common cosmetic role.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- natural
- Evidence
- strong
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Black Iron Oxide is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Black Iron Oxide.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
strongThere is a stronger practical or research basis for the ingredient role described here.
What it is
Black iron oxide (CI 27755) is a naturally occurring mineral pigment composed of iron and oxygen. It is ground into a fine powder and used to impart a black color to cosmetic products. It is one of several iron oxide pigments (including red, yellow, and brown) commonly used in makeup.
How it works
In a cosmetic product, black iron oxide particles sit on the surface of the skin or hair, reflecting and absorbing light to create a black color. It does not penetrate the skin or interact with biological processes. Its primary role is purely aesthetic—to tint the product to the desired shade.
Pros
Safe and widely approved
Black iron oxide is approved by the FDA and other global regulators for use in cosmetics, with a long history of safe use.
Color stability
Unlike some organic dyes, black iron oxide is very stable—it won't fade or change color when exposed to light, heat, or air.
Cons and cautions
No skincare benefits
This ingredient adds color only. It does not moisturize, protect, or treat the skin in any way.
Potential for staining
In high concentrations or poorly formulated products, black iron oxide can temporarily stain skin or clothing, especially if not properly washed off.
Best for
- Anyone looking for a black pigment in their makeup
- People with normal to oily skin who want long-lasting color
- Those who prefer mineral-based colorants over synthetic dyes
Use caution if
- Individuals with known iron allergies (rare)
- Those seeking skincare benefits from their color cosmetics
Usage tips
Safety summary
Black iron oxide is considered safe for use in cosmetics by major regulatory bodies including the FDA and the European Commission. It is non-toxic, non-irritating, and non-sensitizing for the vast majority of users. The Cosmetic Ingredient Review (CIR) panel has also concluded it is safe as used in cosmetics.
Research notes
Multiple safety assessments by the FDA, EU SCCS, and CIR have confirmed the safety of iron oxides in cosmetics. Studies show no significant skin irritation, sensitization, or systemic toxicity when used at typical concentrations. No peer-reviewed studies indicate any health risks from topical application of black iron oxide.
Common label clues
- Typical concentration
- 0.1% to 5% depending on desired shade depth
- Regulatory status
- Approved by the FDA as a color additive for cosmetics (21 CFR 73.2250) and by the EU Cosmetics Regulation (Annex IV).
- Common uses
- Foundations, Eyeliners, Mascaras, Lipsticks, Blushes, Pressed powders
- Environmental note
- Iron oxide is a naturally abundant mineral, and its mining and processing have a moderate environmental footprint. However, it is non-toxic and does not bioaccumulate, making it relatively eco-friendly compared to some synthetic colorants.
Good to know
- Black iron oxide is often combined with other iron oxide pigments (red, yellow, brown) to create a wide range of skin-tone shades.
- It is considered a 'mineral' pigment and is often preferred by those seeking natural or clean beauty products.
- Unlike carbon black, black iron oxide is not derived from petroleum, making it a more natural option.
Common questions
What is Black Iron Oxide in beauty products?
Black iron oxide is a mineral pigment that gives a black color to cosmetics. It's made from iron and oxygen, the same elements that cause rust, but processed into a fine, stable powder. You'll find it in foundations, eyeliners, mascaras, and other color cosmetics. It doesn't treat skin or provide any skincare benefits—it's purely for color. The FDA and other global regulators consider it safe for use in cosmetics when used as intended.
What does Black Iron Oxide do in a beauty product?
In a cosmetic product, black iron oxide particles sit on the surface of the skin or hair, reflecting and absorbing light to create a black color. It does not penetrate the skin or interact with biological processes. Its primary role is purely aesthetic—to tint the product to the desired shade.
Is Black Iron Oxide safe for most people?
Black iron oxide is considered safe for use in cosmetics by major regulatory bodies including the FDA and the European Commission. It is non-toxic, non-irritating, and non-sensitizing for the vast majority of users. The Cosmetic Ingredient Review (CIR) panel has also concluded it is safe as used in cosmetics.
Who should be careful with Black Iron Oxide?
Individuals with known iron allergies (rare) Those seeking skincare benefits from their color cosmetics
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.