Ingredient review
PEG-90M
INCI: PEG-90M
PEG-90M is a safe, synthetic thickener that gives a smooth, non-sticky feel to water-based products.
In plain English
PEG-90M is a type of polyethylene glycol with a very large molecular size. In skincare, it acts like a sponge that soaks up water and swells, turning a thin liquid into a thicker, more gel-like consistency. It also leaves a light, invisible film on your skin that can help other ingredients stay put. Because its molecules are too big to absorb into the skin, it sits on the surface and is washed off easily.
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
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
PEG-90M 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 PEG-90M.
- 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
PEG-90M is a synthetic polymer made from repeating ethylene glycol units, with a molecular weight around 90,000 daltons. It belongs to the PEG (polyethylene glycol) family, which are widely used in cosmetics for their water-solubility and mildness.
How it works
When added to water, PEG-90M molecules unwind and entangle, trapping water and increasing the viscosity of the formula. This creates a smooth, spreadable gel or lotion. After application, the water evaporates and leaves a thin, flexible film on the skin that can help lock in moisture and improve the feel of the product.
Pros
Smooth, non-sticky texture
PEG-90M creates a silky gel that doesn't leave a heavy or greasy residue, making it ideal for lightweight moisturizers and serums.
Very low irritation risk
Because its large molecules don't penetrate the skin, PEG-90M is considered very gentle and unlikely to cause stinging or redness, even for sensitive skin.
Cons and cautions
Synthetic ingredient
PEG-90M is made from petroleum-derived ethylene oxide, which may be a concern for those seeking natural or 'clean' formulations.
Potential tackiness at high levels
If used in high concentrations, the film it leaves can feel slightly sticky or tacky, especially in humid conditions.
Best for
- Anyone who enjoys lightweight, water-based gels or serums
- People with oily or combination skin looking for a non-greasy texture
Use caution if
- Those who strictly avoid all synthetic ingredients
Usage tips
Safety summary
PEG-90M is considered safe for topical use. Its high molecular weight prevents skin penetration, minimizing systemic exposure. It has a low irritation and comedogenic profile.
Research notes
The Cosmetic Ingredient Review (CIR) panel has reviewed PEG compounds and concluded that PEGs with molecular weights above 1,000 are safe in cosmetics. No significant human or animal toxicity has been reported for PEG-90M.
Common label clues
- Typical concentration
- 0.1% to 2%
- Regulatory status
- Approved for use in cosmetics by the FDA and the European Commission. The Cosmetic Ingredient Review (CIR) panel has deemed PEGs of this molecular weight safe as used.
- Common uses
- Serums, Gels, Lotions, Creams
- Environmental note
- PEG compounds are generally biodegradable, but their production relies on fossil fuels. Some environmental concerns exist regarding ethylene oxide manufacturing.
Good to know
- PEG-90M is not absorbed by the skin due to its large molecular size.
- It is often used in 'peel-off' masks because of its film-forming ability.
Common questions
What is PEG-90M in beauty products?
PEG-90M is a type of polyethylene glycol with a very large molecular size. In skincare, it acts like a sponge that soaks up water and swells, turning a thin liquid into a thicker, more gel-like consistency. It also leaves a light, invisible film on your skin that can help other ingredients stay put. Because its molecules are too big to absorb into the skin, it sits on the surface and is washed off easily.
What does PEG-90M do in a beauty product?
When added to water, PEG-90M molecules unwind and entangle, trapping water and increasing the viscosity of the formula. This creates a smooth, spreadable gel or lotion. After application, the water evaporates and leaves a thin, flexible film on the skin that can help lock in moisture and improve the feel of the product.
Is PEG-90M safe for most people?
PEG-90M is considered safe for topical use. Its high molecular weight prevents skin penetration, minimizing systemic exposure. It has a low irritation and comedogenic profile.
Who should be careful with PEG-90M?
Those who strictly avoid all synthetic ingredients
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.