Ingredient review
Ceteareth-33
INCI: Ceteareth-33
Ceteareth-33 is a synthetic emulsifier that helps mix oil and water, but it can be mildly irritating for sensitive skin.
In plain English
Ceteareth-33 is a man-made ingredient that helps oil and water blend together in products like cleansers and lotions. It also helps remove dirt and oil from your skin. While it's effective, it can sometimes cause mild irritation, especially if you have sensitive or reactive skin.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Main practical flags: irritation is moderate; clogging risk is low.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- moderate
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Ceteareth-33 can be useful, but watch for some irritation potential.
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 Ceteareth-33.
- 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
moderateCan bother some users, especially with frequent use, damaged skin, or strong companion ingredients.
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
Ceteareth-33 is a synthetic surfactant and emulsifier derived from cetearyl alcohol and ethylene oxide. It belongs to the ceteareth family of ingredients, which are commonly used in cosmetics to stabilize mixtures and improve cleansing.
How it works
In a cosmetic product, Ceteareth-33 reduces the surface tension between oil and water, allowing them to mix into a stable emulsion. This helps cleansers remove sebum and makeup, and helps lotions feel smooth and uniform. It also has mild foaming properties.
Pros
Effective emulsifier
Ceteareth-33 reliably blends oil and water, giving lotions and cleansers a stable, pleasant texture.
Good cleansing power
It helps remove excess oil, makeup, and impurities from the skin, making it useful in daily cleansers.
Cons and cautions
Potential irritation
As a synthetic surfactant, it can strip the skin's natural moisture barrier and cause mild irritation, especially with frequent use on sensitive skin.
Not natural
It is made through chemical processing, which may be a drawback for those seeking natural or minimal-ingredient routines.
Best for
- People with normal to oily skin looking for effective cleansers
- Those who use well-formulated commercial products without irritation
Use caution if
- Individuals with very sensitive, eczema-prone, or damaged skin who may react to surfactants
Usage tips
Safety summary
Ceteareth-33 is generally safe for most people in rinse-off products, but it can cause mild irritation in sensitive individuals. It is not considered a major allergen or comedogenic.
Research notes
Studies show that ceteareth-type surfactants are effective emulsifiers with low acute toxicity. Irritation potential is dose-dependent and higher in leave-on applications. Regulatory panels (e.g., CIR) have deemed them safe within recommended concentrations.
Common label clues
- Typical concentration
- 1–5% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions, with concentration limits in some leave-on products.
- Common uses
- Cleansers, Shampoos, Body washes, Lotions
- Environmental note
- As a synthetic ethoxylated ingredient, its production involves ethylene oxide, which has environmental and safety considerations. However, it is biodegradable under standard conditions.
Good to know
- Ceteareth-33 is often found in combination with other mild surfactants to reduce irritation.
- It is considered safe in typical concentrations by major regulatory bodies, but individual sensitivity varies.
Common questions
What is Ceteareth-33 in beauty products?
Ceteareth-33 is a man-made ingredient that helps oil and water blend together in products like cleansers and lotions. It also helps remove dirt and oil from your skin. While it's effective, it can sometimes cause mild irritation, especially if you have sensitive or reactive skin.
What does Ceteareth-33 do in a beauty product?
In a cosmetic product, Ceteareth-33 reduces the surface tension between oil and water, allowing them to mix into a stable emulsion. This helps cleansers remove sebum and makeup, and helps lotions feel smooth and uniform. It also has mild foaming properties.
Is Ceteareth-33 safe for most people?
Ceteareth-33 is generally safe for most people in rinse-off products, but it can cause mild irritation in sensitive individuals. It is not considered a major allergen or comedogenic.
Who should be careful with Ceteareth-33?
Individuals with very sensitive, eczema-prone, or damaged skin who may react to surfactants
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.