Ingredient review
PEG-40 Sorbitan Perisostearate
INCI: PEG-40 SORBITAN PERISOSTEARATE
A reliable synthetic emulsifier that helps blend oil and water, generally well-tolerated but may not suit those avoiding ethoxylated ingredients.
In plain English
PEG-40 Sorbitan Perisostearate is a man-made ingredient that helps oil and water stay mixed together in products like lotions and cleansers. The 'PEG' part means it has been processed with ethylene oxide to make it water-friendly, while the 'sorbitan perisostearate' part is derived from a sugar alcohol and a fatty acid, giving it oil-loving properties. This dual nature allows it to create stable, smooth emulsions that don't separate on the shelf.
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-40 Sorbitan Perisostearate 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-40 Sorbitan Perisostearate.
- 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 synthetic emulsifier created by reacting sorbitan (a sugar alcohol) with perisostearic acid (a branched fatty acid) and then adding 40 units of ethylene oxide (PEG-40). It belongs to the PEG surfactant family and is used to stabilize oil-in-water emulsions.
How it works
In a formula, PEG-40 Sorbitan Perisostearate positions itself at the boundary between oil and water droplets. Its water-loving (hydrophilic) PEG chain extends into water, while its oil-loving (lipophilic) sorbitan perisostearate tail embeds in oil. This reduces surface tension and prevents the two phases from separating, giving the product a uniform texture and feel.
Pros
Effective emulsifier
Creates stable, smooth mixtures of oil and water, preventing separation and ensuring a consistent product texture.
Low irritation potential
Generally well-tolerated by most skin types, with low reported irritation and comedogenic ratings.
Cons and cautions
Ethoxylation concerns
The manufacturing process can produce trace amounts of 1,4-dioxane, a potential carcinogen, though reputable brands purify to safe levels.
Not eco-friendly
Synthetic and not readily biodegradable; may also be derived from palm oil, raising sustainability questions.
Best for
- People using conventional moisturizers and cleansers
- Those looking for reliable, cost-effective emulsifiers in stable formulas
Use caution if
- Individuals who prefer to avoid ethoxylated ingredients or PEG compounds
- Those with very sensitive or reactive skin (though irritation is rare)
Usage tips
Safety summary
PEG-40 Sorbitan Perisostearate is considered safe for use in cosmetics at typical concentrations. The main concern is trace 1,4-dioxane from ethoxylation, but reputable manufacturers purify to levels below safety thresholds. Irritation and allergy are rare.
Research notes
The Cosmetic Ingredient Review (CIR) panel has reviewed PEG compounds and found them safe for cosmetic use when formulated to minimize impurities. No specific studies on PEG-40 Sorbitan Perisostearate were found, but it is structurally similar to other PEG sorbitan esters that are well-tolerated.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics by the FDA (as part of generally recognized safe ingredients) and by the European Commission under the CosIng database. The Cosmetic Ingredient Review (CIR) panel has reviewed PEG compounds and found them safe when formulated to minimize impurities.
- Common uses
- Moisturizers, Cleansers, Sunscreens, Makeup removers
- Environmental note
- Synthetic and not readily biodegradable. May be derived from palm oil, so look for sustainably sourced versions if environmental impact is a concern.
Good to know
- PEG-40 Sorbitan Perisostearate is often used in combination with other emulsifiers to fine-tune texture.
- The number '40' refers to the average number of ethylene oxide units, which affects its water solubility.
- It is considered safe by major regulatory bodies when used in cosmetic concentrations.
Common questions
What is PEG-40 Sorbitan Perisostearate in beauty products?
PEG-40 Sorbitan Perisostearate is a man-made ingredient that helps oil and water stay mixed together in products like lotions and cleansers. The 'PEG' part means it has been processed with ethylene oxide to make it water-friendly, while the 'sorbitan perisostearate' part is derived from a sugar alcohol and a fatty acid, giving it oil-loving properties. This dual nature allows it to create stable, smooth emulsions that don't separate on the shelf.
What does PEG-40 Sorbitan Perisostearate do in a beauty product?
In a formula, PEG-40 Sorbitan Perisostearate positions itself at the boundary between oil and water droplets. Its water-loving (hydrophilic) PEG chain extends into water, while its oil-loving (lipophilic) sorbitan perisostearate tail embeds in oil. This reduces surface tension and prevents the two phases from separating, giving the product a uniform texture and feel.
Is PEG-40 Sorbitan Perisostearate safe for most people?
PEG-40 Sorbitan Perisostearate is considered safe for use in cosmetics at typical concentrations. The main concern is trace 1,4-dioxane from ethoxylation, but reputable manufacturers purify to levels below safety thresholds. Irritation and allergy are rare.
Who should be careful with PEG-40 Sorbitan Perisostearate?
Individuals who prefer to avoid ethoxylated ingredients or PEG compounds Those with very sensitive or reactive skin (though irritation is 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.