Ingredient review
PEG-20 Hydrogenated Castor Oil Triisostearate
INCI: PEG-20 HYDROGENATED CASTOR OIL TRIISOSTEARATE
A gentle emulsifier that helps mix oil and water in cleansers and creams, with a low risk of irritation or clogging pores.
In plain English
This ingredient is a helper that allows oil and water to blend together in products like cleansers and lotions. It is made from castor oil that has been chemically modified to be more stable and mixable. In a formula, it helps create a smooth, even texture and can also help remove makeup and sunscreen when you wash your face.
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
PEG-20 Hydrogenated Castor Oil Triisostearate 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-20 Hydrogenated Castor Oil Triisostearate.
- 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 semi-synthetic compound created by reacting hydrogenated castor oil with ethylene oxide and isostearic acid. It belongs to the PEG (polyethylene glycol) family of emulsifiers, which are widely used in cosmetics to stabilize oil-and-water mixtures.
How it works
It reduces the surface tension between oil and water, allowing them to form a stable emulsion. In cleansers, it helps lift and disperse oils, makeup, and sunscreen so they can be rinsed away. In creams, it keeps the product from separating and gives a smooth, even application.
Pros
Gentle emulsifier
It effectively blends oil and water without stripping the skin, making it suitable for daily cleansers and moisturizers.
Low irritation risk
Compared to harsher surfactants, this ingredient has a low potential for causing redness or stinging, even on sensitive skin.
Cons and cautions
Ethoxylation concerns
The manufacturing process can create trace amounts of 1,4-dioxane, a potential contaminant. Reputable brands purify their ingredients to remove it.
Not fully natural
Although derived from castor oil, it is chemically modified and not considered a natural ingredient by clean beauty standards.
Best for
- People looking for gentle, non-stripping cleansers
- Those with normal to combination skin who use makeup or sunscreen
Use caution if
- Individuals with known sensitivity to PEG compounds (rare)
- Those seeking fully natural or biodegradable formulas
Usage tips
Safety summary
Generally recognized as safe for cosmetic use at typical concentrations. The main concern is potential 1,4-dioxane contamination, which is minimized through purification. No significant irritation or comedogenicity has been reported.
Research notes
The Cosmetic Ingredient Review (CIR) panel has evaluated PEG compounds and concluded they are safe for use in cosmetics when formulated properly. No recent peer-reviewed studies specifically highlight risks for this ingredient.
Common label clues
- Typical concentration
- 1–5% in rinse-off products; lower in leave-on products
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions. The CIR panel has reviewed it and found it safe as used in rinse-off and leave-on products.
- Common uses
- Cleansers, Makeup removers, Lotions, Creams
- Environmental note
- PEG compounds can be slow to biodegrade in aquatic environments. Some brands choose alternative emulsifiers for eco-friendly lines.
Good to know
- PEG-20 Hydrogenated Castor Oil Triisostearate is often used in micellar waters and oil-based cleansers
- It is considered safe by the Cosmetic Ingredient Review (CIR) panel at typical use levels
Common questions
What is PEG-20 Hydrogenated Castor Oil Triisostearate in beauty products?
This ingredient is a helper that allows oil and water to blend together in products like cleansers and lotions. It is made from castor oil that has been chemically modified to be more stable and mixable. In a formula, it helps create a smooth, even texture and can also help remove makeup and sunscreen when you wash your face.
What does PEG-20 Hydrogenated Castor Oil Triisostearate do in a beauty product?
It reduces the surface tension between oil and water, allowing them to form a stable emulsion. In cleansers, it helps lift and disperse oils, makeup, and sunscreen so they can be rinsed away. In creams, it keeps the product from separating and gives a smooth, even application.
Is PEG-20 Hydrogenated Castor Oil Triisostearate safe for most people?
Generally recognized as safe for cosmetic use at typical concentrations. The main concern is potential 1,4-dioxane contamination, which is minimized through purification. No significant irritation or comedogenicity has been reported.
Who should be careful with PEG-20 Hydrogenated Castor Oil Triisostearate?
Individuals with known sensitivity to PEG compounds (rare) Those seeking fully natural or biodegradable formulas
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.