Ingredient review
PEG-25 Castor Oil
INCI: PEG-25 Castor Oil
A gentle, water-soluble emulsifier derived from castor oil that helps blend oil and water in cleansers and shampoos.
In plain English
PEG-25 Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it water-soluble. In simple terms, it helps mix oil and water together so that cleansers can effectively remove dirt, makeup, and excess oil without leaving a greasy residue. It's commonly found in gentle cleansers and shampoos.
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-25 Castor Oil 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-25 Castor Oil.
- 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-25 Castor Oil is a semi-synthetic ingredient created by reacting castor oil with 25 units of ethylene oxide (PEG). This process makes the naturally oil-soluble castor oil water-soluble, allowing it to act as a surfactant and emulsifier in cosmetic formulations.
How it works
In a cosmetic product, PEG-25 Castor Oil reduces the surface tension between oil and water, allowing them to mix into a stable emulsion. This helps cleansers and shampoos lift and rinse away dirt, oil, and makeup. It also helps other ingredients spread evenly on the skin or hair.
Pros
Effective emulsifier
Helps cleansers and shampoos mix oil and water, making them more effective at removing dirt and makeup without leaving a greasy film.
Gentle on skin
Generally considered low-irritation and suitable for sensitive skin when used in properly formulated products.
Cons and cautions
Potential impurities
Poorly refined versions may contain trace amounts of ethylene oxide or 1,4-dioxane, which are potential irritants. Reputable brands use high-quality, purified sources.
Not for PEG-free routines
If you avoid PEG compounds for personal reasons, this ingredient is not suitable.
Best for
- People with normal to oily skin looking for a gentle cleanser
- Those who prefer water-soluble makeup removers
Use caution if
- Individuals with known sensitivity to PEG compounds or ethylene oxide derivatives
Usage tips
Safety summary
PEG-25 Castor Oil is considered safe for use in cosmetics at typical concentrations. The main concern is the potential presence of impurities like 1,4-dioxane in poorly refined versions, but reputable manufacturers use purification steps to minimize this risk. It is generally non-irritating and non-comedogenic.
Research notes
The Cosmetic Ingredient Review (CIR) panel has reviewed PEG castor oils and concluded they are safe for use in cosmetics. Studies show low skin irritation and sensitization potential. No significant health risks have been identified when used as intended.
Common label clues
- Typical concentration
- 1–10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database. The Cosmetic Ingredient Review (CIR) panel has deemed PEG castor oils safe as used in cosmetics.
- Common uses
- Cleansers, Shampoos, Conditioners, Facial washes, Makeup removers
- Environmental note
- PEG compounds are generally biodegradable, but their production involves ethylene oxide, which is derived from fossil fuels. Some environmental groups raise concerns about potential byproducts.
Good to know
- PEG-25 Castor Oil is different from plain castor oil—it's water-soluble and less likely to clog pores
- The number '25' refers to the average number of ethylene oxide units added, which affects water solubility and mildness
Common questions
What is PEG-25 Castor Oil in beauty products?
PEG-25 Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it water-soluble. In simple terms, it helps mix oil and water together so that cleansers can effectively remove dirt, makeup, and excess oil without leaving a greasy residue. It's commonly found in gentle cleansers and shampoos.
What does PEG-25 Castor Oil do in a beauty product?
In a cosmetic product, PEG-25 Castor Oil reduces the surface tension between oil and water, allowing them to mix into a stable emulsion. This helps cleansers and shampoos lift and rinse away dirt, oil, and makeup. It also helps other ingredients spread evenly on the skin or hair.
Is PEG-25 Castor Oil safe for most people?
PEG-25 Castor Oil is considered safe for use in cosmetics at typical concentrations. The main concern is the potential presence of impurities like 1,4-dioxane in poorly refined versions, but reputable manufacturers use purification steps to minimize this risk. It is generally non-irritating and non-comedogenic.
Who should be careful with PEG-25 Castor Oil?
Individuals with known sensitivity to PEG compounds or ethylene oxide derivatives
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.