Ingredient review
Sulfated Castor Oil
INCI: Sulfated Castor Oil
A mild, plant-derived surfactant that cleans without stripping, but may feel heavy on oily skin types.
In plain English
Sulfated castor oil is castor oil that has been chemically treated to make it water-soluble and soap-like. It helps cleanse the skin and hair by lifting dirt and oil, but it's much gentler than many synthetic detergents. Historically known as Turkey Red Oil, it was one of the first synthetic surfactants used in personal care.
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
Sulfated 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 Sulfated 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
A semi-synthetic surfactant made by reacting castor oil with sulfuric acid, creating a mild cleansing agent that is both water- and oil-soluble.
How it works
It reduces the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Because it is derived from a fatty oil, it also leaves a light moisturizing film on the skin.
Pros
Very gentle cleanser
Sulfated castor oil cleanses without stripping the skin's natural moisture barrier, making it ideal for dry or sensitive skin.
Plant-derived and biodegradable
Made from renewable castor oil, it is considered more environmentally friendly than many petroleum-based surfactants.
Cons and cautions
Low foam
It produces minimal lather compared to sodium lauryl sulfate, which may be less satisfying for users who prefer a foamy wash.
Potential residue on oily skin
Because it retains some fatty character, it can leave a slight film that might feel heavy for those with very oily skin.
Best for
- People with dry or sensitive skin looking for a mild cleanser
- Those who prefer plant-derived ingredients over harsh sulfates
Use caution if
- Individuals with very oily or acne-prone skin who may find it too emollient
Usage tips
Safety summary
Sulfated castor oil is considered safe for topical use with low irritation potential. It is not a strong detergent and is well-tolerated by most skin types.
Research notes
Limited modern clinical studies, but historical use and cosmetic ingredient safety reviews support its safety as a mild surfactant. It is listed in the CosIng database and accepted by the FDA as a safe cosmetic ingredient.
Common label clues
- Typical concentration
- 1–10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. No specific restrictions beyond general cosmetic safety requirements.
- Common uses
- Cleansers, Bath oils, Shampoos, Bar soaps
- Environmental note
- Castor oil is a renewable plant resource, and sulfated castor oil is biodegradable, making it a relatively eco-friendly surfactant choice.
Good to know
- Sulfated castor oil is also known as Turkey Red Oil, a name from its historical use in textile dyeing.
- It is not the same as 'sulfated' in the sense of sulfate detergents like SLS; it is much milder.
Common questions
What is Sulfated Castor Oil in beauty products?
Sulfated castor oil is castor oil that has been chemically treated to make it water-soluble and soap-like. It helps cleanse the skin and hair by lifting dirt and oil, but it's much gentler than many synthetic detergents. Historically known as Turkey Red Oil, it was one of the first synthetic surfactants used in personal care.
What does Sulfated Castor Oil do in a beauty product?
It reduces the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Because it is derived from a fatty oil, it also leaves a light moisturizing film on the skin.
Is Sulfated Castor Oil safe for most people?
Sulfated castor oil is considered safe for topical use with low irritation potential. It is not a strong detergent and is well-tolerated by most skin types.
Who should be careful with Sulfated Castor Oil?
Individuals with very oily or acne-prone skin who may find it too emollient
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.