Ingredient review
Laureth-5 Carboxylic Acid
INCI: LAURETH-5 CARBOXYLIC ACID
A gentle, low-irritation surfactant that helps cleanse without stripping the skin's natural moisture barrier.
In plain English
Laureth-5 Carboxylic Acid is a mild cleansing ingredient often used in soaps and shampoos. It helps lift dirt and oil from the skin and hair while being less harsh than traditional sulfates. Think of it as a gentle cleaner that doesn't leave your 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-5 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-5 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 lauryl alcohol (from coconut or palm oil) with ethylene oxide and then adding a carboxylic acid group. It belongs to the ether carboxylic acid family, known for mildness and good foaming properties.
How it works
In a cosmetic product, Laureth-5 Carboxylic Acid works by reducing the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Its carboxylic acid group gives it a slightly negative charge, which helps it interact gently with the skin's surface without disrupting the natural lipid barrier.
Pros
Gentle on skin
Laureth-5 Carboxylic Acid is much less irritating than common sulfates, making it suitable for sensitive or dry skin types.
Effective cleaner
It removes dirt, oil, and makeup without stripping the skin's natural moisture barrier, leaving skin feeling comfortable.
Cons and cautions
Potential contaminant concern
As an ethoxylated ingredient, it may contain trace amounts of 1,4-dioxane, a possible carcinogen, if not properly purified. Reputable manufacturers ensure low levels.
Sustainability issues
Often derived from palm oil, which can be linked to deforestation. Look for certified sustainable sources if this matters to you.
Best for
- People with dry or sensitive skin looking for a gentle cleanser
- Anyone wanting to avoid harsh sulfates like sodium lauryl sulfate (SLS)
Use caution if
- Those with known allergies to ethoxylated ingredients (rare)
Usage tips
Safety summary
Laureth-5 Carboxylic Acid is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential presence of 1,4-dioxane, but reputable manufacturers keep levels well below regulatory limits. Overall, it is a low-irritation, well-tolerated ingredient.
Research notes
Studies on ether carboxylic acids show they are milder than traditional anionic surfactants like SLS. Research indicates they cause less protein denaturation and lipid barrier disruption, making them suitable for sensitive skin. However, specific studies on Laureth-5 Carboxylic Acid are limited.
Common label clues
- Typical concentration
- Typically 1–10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. The Cosmetic Ingredient Review (CIR) panel has reviewed similar ethoxylated surfactants and found them safe when formulated properly.
- Common uses
- Facial cleansers, Body washes, Shampoos, Micellar waters
- Environmental note
- Derived from lauryl alcohol, which can come from coconut or palm oil. Palm oil sourcing may have environmental impacts; look for RSPO-certified or coconut-derived versions.
Good to know
- Laureth-5 Carboxylic Acid is often listed as 'Laureth-5 Carboxylate' on ingredient labels.
- It is considered a 'secondary surfactant' and is rarely used alone; it works best in combination with other cleansing agents.
Common questions
What is Laureth-5 Carboxylic Acid in beauty products?
Laureth-5 Carboxylic Acid is a mild cleansing ingredient often used in soaps and shampoos. It helps lift dirt and oil from the skin and hair while being less harsh than traditional sulfates. Think of it as a gentle cleaner that doesn't leave your skin feeling tight or dry.
What does Laureth-5 Carboxylic Acid do in a beauty product?
In a cosmetic product, Laureth-5 Carboxylic Acid works by reducing the surface tension between water and oil, allowing dirt and sebum to be rinsed away. Its carboxylic acid group gives it a slightly negative charge, which helps it interact gently with the skin's surface without disrupting the natural lipid barrier.
Is Laureth-5 Carboxylic Acid safe for most people?
Laureth-5 Carboxylic Acid is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential presence of 1,4-dioxane, but reputable manufacturers keep levels well below regulatory limits. Overall, it is a low-irritation, well-tolerated ingredient.
Who should be careful with Laureth-5 Carboxylic Acid?
Those 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.