Ingredient review
Quaternium-90 Sepiolite
INCI: QUATERNIUM-90 SEPIOLITE
A gentle clay-derived thickener that improves product feel without common irritation concerns.
In plain English
Quaternium-90 Sepiolite is a modified clay mineral. Think of it as a super-fine, treated clay that helps give creams and lotions a smooth, silky texture. It's not an active skincare ingredient like vitamin C or retinol, but it plays a supporting role by making the product feel nicer on your skin and helping it spread evenly.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
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
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Quaternium-90 Sepiolite 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 Quaternium-90 Sepiolite.
- 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 chemically modified form of sepiolite, a natural clay mineral. The 'quaternium' part means it has been treated with a quaternary ammonium compound to change its surface properties, making it more compatible with oils and other ingredients in cosmetic formulas.
How it works
It works by absorbing water and swelling, which thickens the product. Its tiny, needle-like particles also help create a smooth, creamy texture and can prevent other ingredients from separating. On the skin, it leaves a soft, powdery feel and can help mattify shine.
Pros
Gentle on skin
Quaternium-90 Sepiolite has a very low irritation and comedogenic risk, making it suitable for sensitive and acne-prone skin types.
Improves product feel
It creates a smooth, silky texture that makes creams and lotions feel luxurious and easy to apply, without a heavy or sticky residue.
Cons and cautions
No active skincare benefit
This ingredient is purely a texture enhancer. It does not hydrate, brighten, or provide any direct skin benefit beyond improving the product's feel.
Potential for dryness
Because it can absorb oil and water, formulas with a high concentration may feel drying or tight on very dry or dehydrated skin.
Best for
- People who prefer lightweight, non-greasy textures
- Those with oily or combination skin looking for a matte finish
Use caution if
- Individuals with extremely dry or dehydrated skin who may find clay-based thickeners too absorbent
Usage tips
Safety summary
Quaternium-90 Sepiolite is considered safe for use in cosmetics. It has a low potential for skin irritation and is not known to clog pores. However, as with any ingredient, individual sensitivity is possible.
Research notes
Safety assessments by cosmetic ingredient review panels have found modified clays like this to be safe at typical use levels. Most evidence is based on general clay safety and formulation experience rather than specific clinical studies on this exact ingredient.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in most regions, including the EU and US, with no known restrictions at typical use levels.
- Common uses
- Creams, Lotions, Masks, Foundations
- Environmental note
- The clay is a natural resource, but the chemical modification process may have environmental considerations. It is not known to be biodegradable.
Good to know
- Sepiolite is a natural clay mined from the earth, but the quaternium treatment makes it semi-synthetic.
- It is often used as a safer alternative to some traditional thickeners that can be more irritating.
Common questions
What is Quaternium-90 Sepiolite in beauty products?
Quaternium-90 Sepiolite is a modified clay mineral. Think of it as a super-fine, treated clay that helps give creams and lotions a smooth, silky texture. It's not an active skincare ingredient like vitamin C or retinol, but it plays a supporting role by making the product feel nicer on your skin and helping it spread evenly.
What does Quaternium-90 Sepiolite do in a beauty product?
It works by absorbing water and swelling, which thickens the product. Its tiny, needle-like particles also help create a smooth, creamy texture and can prevent other ingredients from separating. On the skin, it leaves a soft, powdery feel and can help mattify shine.
Is Quaternium-90 Sepiolite safe for most people?
Quaternium-90 Sepiolite is considered safe for use in cosmetics. It has a low potential for skin irritation and is not known to clog pores. However, as with any ingredient, individual sensitivity is possible.
Who should be careful with Quaternium-90 Sepiolite?
Individuals with extremely dry or dehydrated skin who may find clay-based thickeners too absorbent
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.