Ingredient review

Ceteareth-29

INCI: Ceteareth-29

Ceteareth-29 is a gentle, synthetic emulsifier that helps mix water and oil in creams and lotions, with a low risk of irritation.

beautyskincareemulsifier

In plain English

Ceteareth-29 is a man-made ingredient that acts like a bridge between water and oil in your skincare products. Without it, many creams and lotions would separate into watery and oily layers. It helps create a smooth, stable texture so your moisturizer or cleanser feels consistent every time you use it. It is part of a family of ingredients called ethoxylated alcohols, which are processed to be mild on skin.

Review score

Safety, usefulness, and evidence

4.0Good
4.0/ 5

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
How reviews are scored

Quick decision guide

Useful, but context matters

Ceteareth-29 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.

  1. Step 1Start with the score, then check the irritation and clogging risk before judging Ceteareth-29.
  2. Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
  3. 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

low

Less likely to sting, burn, or bother most users, though sensitive skin can still react.

Clogging risk

low

Less likely to feel heavy or contribute to clogged pores for most skin types.

Evidence level

moderate

There is useful support, but formula details and claim strength still matter.

What it is

Ceteareth-29 is a synthetic emulsifier derived from cetearyl alcohol (a fatty alcohol from plant or petroleum sources) that has been reacted with ethylene oxide. It belongs to the ceteareth family, where the number (29) indicates the average length of the polyethylene glycol chain.

How it works

In a cosmetic product, ceteareth-29 reduces the surface tension between water and oil droplets, allowing them to mix into a stable emulsion. This prevents separation and gives the product a uniform, creamy texture. It also helps other ingredients spread evenly on the skin.

Pros

Gentle on skin

Ceteareth-29 has a low irritation risk, making it suitable for sensitive skin types when used in properly formulated products.

Improves product stability

It prevents oil and water from separating, so your moisturizer or lotion stays smooth and effective throughout its shelf life.

Cons and cautions

Potential trace impurities

The manufacturing process can leave very small amounts of 1,4-dioxane, a possible carcinogen, though reputable brands keep levels well below safety limits.

Environmental persistence

As a synthetic ethoxylate, it may not break down quickly in the environment, which is a concern for eco-conscious consumers.

Best for

  • Anyone using creams, lotions, or cleansers that need a stable texture
  • People with normal to dry skin looking for gentle emulsifiers

Use caution if

  • Those with a known allergy to ethoxylated ingredients (rare)

Usage tips

Look for products from brands that test for 1,4-dioxane purity to ensure safety
Use as part of a complete formulation; it is not sold as a standalone skincare ingredient

Safety summary

Ceteareth-29 is considered safe for use in cosmetics at typical concentrations. The main concern is trace 1,4-dioxane from manufacturing, but regulatory limits keep exposure very low. It has low skin irritation and comedogenic potential.

Research notes

Safety assessments by the Cosmetic Ingredient Review (CIR) panel have found ceteareth compounds safe for cosmetic use when formulated properly. Studies focus on irritation and impurity levels rather than direct skin benefits.

Common label clues

Typical concentration
Typically 0.5% to 5% of the formula
Regulatory status
Approved for use in cosmetics in the US (FDA) and EU (CosIng) with no concentration restrictions, though manufacturers must limit 1,4-dioxane impurities to safe levels.
Common uses
Cleansers, Moisturizers, Lotions, Creams
Environmental note
Ceteareth-29 is not readily biodegradable, so it may accumulate in water systems. Some brands are moving toward more eco-friendly alternatives.

Good to know

  • The number '29' in ceteareth-29 refers to the average number of ethylene oxide units, which affects its water solubility and mildness.
  • It is often used alongside other emulsifiers to create a balanced formula.

Common questions

What is Ceteareth-29 in beauty products?

Ceteareth-29 is a man-made ingredient that acts like a bridge between water and oil in your skincare products. Without it, many creams and lotions would separate into watery and oily layers. It helps create a smooth, stable texture so your moisturizer or cleanser feels consistent every time you use it. It is part of a family of ingredients called ethoxylated alcohols, which are processed to be mild on skin.

What does Ceteareth-29 do in a beauty product?

In a cosmetic product, ceteareth-29 reduces the surface tension between water and oil droplets, allowing them to mix into a stable emulsion. This prevents separation and gives the product a uniform, creamy texture. It also helps other ingredients spread evenly on the skin.

Is Ceteareth-29 safe for most people?

Ceteareth-29 is considered safe for use in cosmetics at typical concentrations. The main concern is trace 1,4-dioxane from manufacturing, but regulatory limits keep exposure very low. It has low skin irritation and comedogenic potential.

Who should be careful with Ceteareth-29?

Those with a known allergy to ethoxylated ingredients (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.