Ingredient review
Laureth-13 Carboxylic Acid
INCI: Laureth-13 Carboxylic Acid
A gentle, low-irritation surfactant that helps cleansers foam and remove dirt without stripping the skin.
In plain English
Laureth-13 carboxylic acid is a mild cleansing ingredient often used in facial washes and body cleansers. It helps water and oil mix so that dirt and makeup can be rinsed away easily. Unlike harsher soaps, it is designed to clean without leaving skin feeling tight or dry.
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
Laureth-13 Carboxylic Acid 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 Laureth-13 Carboxylic Acid.
- 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 lauric acid (from coconut or palm oil) with ethylene oxide, then modifying it to form a carboxylic acid group. It belongs to the class of alkyl ether carboxylic acids, known for their gentle cleansing properties.
How it works
In a cleanser, laureth-13 carboxylic acid lowers the surface tension between water and oil, allowing oily impurities to be lifted from the skin and suspended in water so they can be rinsed away. Its mildness comes from its large, water-loving head that reduces interaction with skin proteins, minimizing irritation.
Pros
Gentle on skin
Its large molecular structure makes it less likely to penetrate the skin barrier, reducing the risk of irritation and dryness compared to harsher surfactants like sodium lauryl sulfate.
Effective cleanser
It efficiently removes excess oil, dirt, and light makeup without leaving a residue, making it a reliable choice for daily facial cleansers.
Cons and cautions
Potential for slight dryness
In high concentrations or in leave-on products, it may still cause mild tightness for very dry or compromised skin, though this is uncommon.
Synthetic origin
As an ethoxylated ingredient, its production involves ethylene oxide, which raises environmental and processing concerns, though the final ingredient is considered safe for use.
Best for
- People with normal to combination skin looking for a gentle daily cleanser
- Those who prefer sulfate-free or low-irritation cleansing products
Use caution if
- Individuals with known allergies to ethoxylated ingredients (rare)
Usage tips
Safety summary
Laureth-13 carboxylic acid is considered safe for cosmetic use at typical concentrations. It has low acute toxicity and is not a significant skin sensitizer. Mild irritation is possible only in high concentrations or in individuals with very sensitive skin.
Research notes
Research on alkyl ether carboxylic acids shows they are milder than traditional anionic surfactants like SLS. Studies indicate they cause less protein denaturation and lower skin barrier disruption, making them suitable for sensitive skin formulations.
Common label clues
- Typical concentration
- 1–10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics in the EU, US, and other major markets. The Cosmetic Ingredient Review (CIR) panel has evaluated alkyl ether carboxylic acids as safe when formulated to be non-irritating.
- Common uses
- Facial cleansers, Body washes, Shampoos, Makeup removers
- Environmental note
- Ethoxylated surfactants can have variable biodegradability. Some studies indicate that longer-chain ethoxylates may persist longer in aquatic environments, but modern formulations often use biodegradable variants.
Good to know
- Laureth-13 carboxylic acid is often used in 'sulfate-free' cleansers as a primary or secondary surfactant.
- It is not a soap; it is a synthetic detergent that works well in hard water without forming scum.
Common questions
What is Laureth-13 Carboxylic Acid in beauty products?
Laureth-13 carboxylic acid is a mild cleansing ingredient often used in facial washes and body cleansers. It helps water and oil mix so that dirt and makeup can be rinsed away easily. Unlike harsher soaps, it is designed to clean without leaving skin feeling tight or dry.
What does Laureth-13 Carboxylic Acid do in a beauty product?
In a cleanser, laureth-13 carboxylic acid lowers the surface tension between water and oil, allowing oily impurities to be lifted from the skin and suspended in water so they can be rinsed away. Its mildness comes from its large, water-loving head that reduces interaction with skin proteins, minimizing irritation.
Is Laureth-13 Carboxylic Acid safe for most people?
Laureth-13 carboxylic acid is considered safe for cosmetic use at typical concentrations. It has low acute toxicity and is not a significant skin sensitizer. Mild irritation is possible only in high concentrations or in individuals with very sensitive skin.
Who should be careful with Laureth-13 Carboxylic Acid?
Individuals with known allergies 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.