Ingredient review
PEG-26 Castor Oil
INCI: PEG-26 Castor Oil
PEG-26 Castor Oil is a gentle, water-soluble emulsifier that helps blend oil and water in cleansers and shampoos, but its PEG component raises mild environmental and purity concerns.
In plain English
PEG-26 Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it dissolve in water. In your shampoo or face wash, it helps mix oily ingredients with water so they rinse away cleanly. It's considered gentle and low-risk for irritation, but some people prefer to avoid PEGs due to potential impurities from manufacturing.
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-26 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-26 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-26 Castor Oil is a semi-synthetic compound created by reacting castor oil with ethylene oxide (forming a PEG chain of 26 units). This process makes the naturally oil-soluble castor oil water-soluble, allowing it to act as a surfactant and emulsifier in cosmetic formulas.
How it works
In a product, PEG-26 Castor Oil sits at the interface between oil and water molecules, reducing surface tension so the two can mix into a stable emulsion. During rinsing, it helps lift dirt, oil, and makeup from the skin or hair and carries them away with water.
Pros
Gentle emulsifier
PEG-26 Castor Oil is mild on skin and hair, making it suitable for daily use in cleansers and shampoos without causing irritation or stripping natural oils.
Versatile formula helper
It stabilizes emulsions and improves texture, so your products feel smooth and rinse off cleanly without leaving a greasy residue.
Cons and cautions
Potential impurities
During manufacturing, PEG compounds can form trace amounts of 1,4-dioxane, a possible carcinogen. Reputable brands purify their ingredients to remove these impurities, but it's a concern for some consumers.
Environmental persistence
The PEG chain makes this ingredient less biodegradable than natural alternatives, which can contribute to aquatic pollution over time.
Best for
- People looking for a gentle, non-stripping cleanser or makeup remover
- Those with normal to combination skin who want effective but mild cleansing
Use caution if
- Individuals who prefer to avoid all PEG-derived ingredients due to personal or environmental concerns
Usage tips
Safety summary
PEG-26 Castor Oil is considered safe for cosmetic use at typical concentrations. The main safety concern is the potential presence of 1,4-dioxane, but this is minimized through purification processes. It is generally non-irritating and non-comedogenic.
Research notes
The Cosmetic Ingredient Review (CIR) has evaluated PEG derivatives and found them safe for use in cosmetics when formulated to minimize impurities. Studies show low skin irritation and sensitization potential for PEG-26 Castor Oil specifically.
Common label clues
- Typical concentration
- 1% to 10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions. The EU restricts the level of 1,4-dioxane impurity in cosmetic ingredients, and reputable manufacturers adhere to these limits.
- Common uses
- Cleansers, Shampoos, Body washes, Makeup removers, Conditioners
- Environmental note
- PEG compounds are not readily biodegradable in aquatic environments, which has led to some scrutiny. However, they are used in low concentrations and wastewater treatment can reduce their impact.
Good to know
- PEG-26 Castor Oil is often listed alongside other PEG numbers (e.g., PEG-40, PEG-60) — higher numbers mean more water solubility.
- It is not the same as pure castor oil, which is thick and not water-soluble.
- The Cosmetic Ingredient Review (CIR) panel has deemed many PEG derivatives safe for use in cosmetics when properly formulated.
Common questions
What is PEG-26 Castor Oil in beauty products?
PEG-26 Castor Oil is a modified version of castor oil that has been treated with polyethylene glycol (PEG) to make it dissolve in water. In your shampoo or face wash, it helps mix oily ingredients with water so they rinse away cleanly. It's considered gentle and low-risk for irritation, but some people prefer to avoid PEGs due to potential impurities from manufacturing.
What does PEG-26 Castor Oil do in a beauty product?
In a product, PEG-26 Castor Oil sits at the interface between oil and water molecules, reducing surface tension so the two can mix into a stable emulsion. During rinsing, it helps lift dirt, oil, and makeup from the skin or hair and carries them away with water.
Is PEG-26 Castor Oil safe for most people?
PEG-26 Castor Oil is considered safe for cosmetic use at typical concentrations. The main safety concern is the potential presence of 1,4-dioxane, but this is minimized through purification processes. It is generally non-irritating and non-comedogenic.
Who should be careful with PEG-26 Castor Oil?
Individuals who prefer to avoid all PEG-derived ingredients due to personal or environmental concerns
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.