Ingredient review
Sodium Aluminum Iron Hydroxide Oxalate Sulfate
INCI: Sodium/Aluminum/Iron Hydroxide/Oxalate/Sulfate
A mineral colorant that adds opacity and tint to makeup, generally considered safe but with limited research on long-term skin absorption.
In plain English
This ingredient is a mix of minerals (sodium, aluminum, iron, hydroxide, oxalate, and sulfate) that gives makeup its color and coverage. Think of it like a natural pigment that helps foundation or powder look smooth and opaque on your skin. It's not an active skincare ingredient, so it doesn't treat or improve skin—it's purely cosmetic.
Review score
Safety, usefulness, and evidence
Useful in the right context, but not low-maintenance
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- natural
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Read the cautions before using
Sodium Aluminum Iron Hydroxide Oxalate Sulfate 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 Sodium Aluminum Iron Hydroxide Oxalate Sulfate.
- 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
moderateThere is useful support, but formula details and claim strength still matter.
What it is
A complex inorganic salt composed of sodium, aluminum, iron, hydroxide, oxalate, and sulfate groups. It is a synthetic or naturally derived mineral pigment used to provide color and opacity in cosmetic formulations.
How it works
When added to a formula, this ingredient scatters and reflects light, creating a matte or opaque finish. It sits on the skin's surface and does not penetrate deeply, so its effect is purely visual—helping products like foundation cover imperfections or give a uniform tint.
Pros
Effective opacifier
Gives makeup a smooth, opaque finish that helps even out skin tone without looking cakey.
Low irritation potential
Generally well-tolerated on skin, making it suitable for most people, including those with sensitive skin.
Cons and cautions
Limited skincare benefit
This ingredient is purely cosmetic—it doesn't hydrate, protect, or improve skin health over time.
Potential absorption concerns
While considered safe at low levels, some research raises questions about aluminum absorption through skin, especially in damaged or compromised barriers.
Best for
- People who want full-coverage, matte makeup
- Those with oily or combination skin who prefer powder-based products
Use caution if
- Individuals with known sensitivity to aluminum or oxalate compounds
Usage tips
Safety summary
Generally recognized as safe for topical use in cosmetics at low concentrations. However, long-term studies on aluminum absorption through intact skin are limited, so caution is advised for broken or compromised skin.
Research notes
Research on this specific complex is sparse. Most safety data comes from studies on individual components (e.g., aluminum salts, iron oxides), which are considered safe in cosmetics. No peer-reviewed studies directly address this exact combination.
Common label clues
- Typical concentration
- Typically used at low levels, often under 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng) as a colorant/opacifier, with no specific restrictions at typical use levels.
- Common uses
- Foundations, Concealers, Powders, Eye shadows
- Environmental note
- Mining and processing of aluminum and iron compounds can have environmental impacts, but the ingredient itself is not considered a major pollutant in cosmetic waste.
Good to know
- This ingredient is often listed alongside other mineral pigments in foundation and concealer ingredient lists.
- It is not a sunscreen agent, even though it contains minerals—don't rely on it for UV protection.
Common questions
What is Sodium Aluminum Iron Hydroxide Oxalate Sulfate in beauty products?
This ingredient is a mix of minerals (sodium, aluminum, iron, hydroxide, oxalate, and sulfate) that gives makeup its color and coverage. Think of it like a natural pigment that helps foundation or powder look smooth and opaque on your skin. It's not an active skincare ingredient, so it doesn't treat or improve skin—it's purely cosmetic.
What does Sodium Aluminum Iron Hydroxide Oxalate Sulfate do in a beauty product?
When added to a formula, this ingredient scatters and reflects light, creating a matte or opaque finish. It sits on the skin's surface and does not penetrate deeply, so its effect is purely visual—helping products like foundation cover imperfections or give a uniform tint.
Is Sodium Aluminum Iron Hydroxide Oxalate Sulfate safe for most people?
Generally recognized as safe for topical use in cosmetics at low concentrations. However, long-term studies on aluminum absorption through intact skin are limited, so caution is advised for broken or compromised skin.
Who should be careful with Sodium Aluminum Iron Hydroxide Oxalate Sulfate?
Individuals with known sensitivity to aluminum or oxalate compounds
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.