Ingredient review
Steareth-27
INCI: STEARETH-27
Steareth-27 is a mild, non-irritating emulsifier that helps create stable, creamy textures in skincare and haircare products.
In plain English
Steareth-27 is a gentle ingredient that helps oil and water mix together in your skincare products, so they stay smooth and don't separate. It's a type of emulsifier made from a fatty alcohol (from plants or synthetic sources) and ethylene oxide. Because it has a long chain of ethylene oxide units, it's very mild and unlikely to irritate your skin. You'll find it in lotions, creams, and cleansers where it helps create a nice, even texture and can also help remove dirt and oil 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
Steareth-27 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 Steareth-27.
- 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
Steareth-27 is a semi-synthetic emulsifier and surfactant. It belongs to the 'steareth' family, which are ethoxylated derivatives of stearyl alcohol. The number '27' refers to the average number of ethylene oxide units in the molecule, which makes it water-soluble and very mild on skin.
How it works
In a cosmetic product, Steareth-27 sits at the boundary between oil and water droplets, reducing surface tension so they can mix into a stable emulsion. This prevents your lotion or cream from separating into watery and oily layers. As a surfactant, it also helps lift dirt and excess oil from your skin's surface, allowing them to be rinsed away with water.
Pros
Very gentle on skin
Steareth-27 has a low irritation potential, making it suitable for sensitive skin types and daily use in leave-on products like moisturizers.
Excellent emulsifier
It creates stable, creamy emulsions that keep oil and water mixed, so your product stays consistent and effective from first use to last.
Cons and cautions
Ethoxylation concerns
The manufacturing process can produce trace amounts of 1,4-dioxane, a potential contaminant. However, reputable brands use purification steps to keep levels well within safety limits.
Not fully natural
As a semi-synthetic ingredient, it may not appeal to consumers seeking 100% natural or organic formulations.
Best for
- People with normal to dry skin who want a rich, stable moisturizer
- Anyone looking for a gentle, non-stripping cleanser
Use caution if
- Those with a known sensitivity to ethoxylated ingredients (rare)
Usage tips
Safety summary
Steareth-27 is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential for trace 1,4-dioxane contamination from manufacturing, but regulatory bodies require purification to keep levels extremely low. Skin irritation and allergy are rare.
Research notes
Safety assessments by the Cosmetic Ingredient Review (CIR) and other bodies have evaluated steareth compounds and found them safe for cosmetic use when formulated properly. Research focuses on their mildness and efficacy as emulsifiers, with no significant evidence of health risks at authorized levels.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA), EU (CosIng), and many other regions. The Cosmetic Ingredient Review (CIR) panel has deemed steareth ingredients safe when formulated to minimize 1,4-dioxane contamination.
- Common uses
- Cleansers, Moisturizers, Lotions, Creams, Shampoos
- Environmental note
- Steareth-27 is not readily biodegradable in aquatic environments, which is a consideration for eco-conscious consumers. However, it is used in low concentrations and wastewater treatment can reduce its impact.
Good to know
- Steareth-27 is often used alongside other emulsifiers to fine-tune texture and stability.
- The '27' in its name indicates a high degree of ethoxylation, which makes it more water-soluble and milder than shorter-chain steareths.
Common questions
What is Steareth-27 in beauty products?
Steareth-27 is a gentle ingredient that helps oil and water mix together in your skincare products, so they stay smooth and don't separate. It's a type of emulsifier made from a fatty alcohol (from plants or synthetic sources) and ethylene oxide. Because it has a long chain of ethylene oxide units, it's very mild and unlikely to irritate your skin. You'll find it in lotions, creams, and cleansers where it helps create a nice, even texture and can also help remove dirt and oil when you wash your face.
What does Steareth-27 do in a beauty product?
In a cosmetic product, Steareth-27 sits at the boundary between oil and water droplets, reducing surface tension so they can mix into a stable emulsion. This prevents your lotion or cream from separating into watery and oily layers. As a surfactant, it also helps lift dirt and excess oil from your skin's surface, allowing them to be rinsed away with water.
Is Steareth-27 safe for most people?
Steareth-27 is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential for trace 1,4-dioxane contamination from manufacturing, but regulatory bodies require purification to keep levels extremely low. Skin irritation and allergy are rare.
Who should be careful with Steareth-27?
Those with a known sensitivity to ethoxylated ingredients (rare)
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.