Ingredient review
Myreth-5 Carboxylic Acid
INCI: MYRETH-5 CARBOXYLIC ACID
A gentle synthetic surfactant that effectively cleanses without the harshness of traditional soaps, making it suitable for sensitive skin.
In plain English
Myreth-5 carboxylic acid is a man-made cleansing ingredient often found in face washes and shampoos. It helps lift dirt and oil from your skin so they can be rinsed away, but it's designed to be much gentler than old-fashioned soaps that can leave your skin feeling tight and dry. Think of it as a mild, hardworking helper that gets your skin clean without overdoing it.
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
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Myreth-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 Myreth-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
Myreth-5 carboxylic acid is a synthetic surfactant derived from myristyl alcohol (a fatty alcohol) and ethylene oxide, then modified with a carboxylic acid group. It belongs to a class of ingredients called ether carboxylic acids, known for their mild cleansing properties.
How it works
In a cosmetic product, myreth-5 carboxylic acid works by reducing the surface tension between water and oil, allowing oily dirt and makeup to be emulsified and rinsed away. Its carboxylic acid group gives it a slightly negative charge, which helps it interact gently with skin proteins, minimizing irritation compared to harsher sulfates.
Pros
Very gentle on skin
Unlike sodium lauryl sulfate, myreth-5 carboxylic acid is designed to clean without stripping your skin's natural moisture barrier, making it ideal for daily use.
Works well in sulfate-free formulas
It provides effective foaming and cleansing without the harshness of sulfates, so you can enjoy a satisfying lather without irritation.
Cons and cautions
Synthetic ingredient
It is manufactured through chemical processes, which may be a drawback if you prefer naturally derived or plant-based ingredients.
Potential for slight dryness at high levels
In some formulations with very high concentrations, it may still cause mild dryness, though this is rare compared to harsher surfactants.
Best for
- People with sensitive or easily irritated skin
- Those looking for a sulfate-free cleanser
- Anyone wanting a gentle daily face wash
Use caution if
- Individuals seeking 100% natural or organic-only ingredients
Usage tips
Safety summary
Myreth-5 carboxylic acid is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for sensitive skin. As with any ingredient, individual reactions are possible, but it is well-tolerated by most people.
Research notes
Research on ether carboxylic acids like myreth-5 carboxylic acid indicates they are mild surfactants with good skin compatibility. While not as extensively studied as some common surfactants, available data from ingredient safety panels and dermatological testing support its safety and gentleness.
Common label clues
- Typical concentration
- Typically 1–10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the EU, US, and many other regions. The Cosmetic Ingredient Review (CIR) panel has reviewed similar ether carboxylic acids and found them safe for use in rinse-off products at typical concentrations.
- Common uses
- Facial cleansers, Body washes, Shampoos, Makeup removers
- Environmental note
- Myreth-5 carboxylic acid is generally considered biodegradable, though its production involves ethylene oxide, which has environmental considerations. Many manufacturers are moving toward greener production methods.
Good to know
- Myreth-5 carboxylic acid is often used in combination with other mild surfactants to create a well-rounded cleansing system.
- It is considered biodegradable and has a good environmental profile compared to some older surfactants.
Common questions
What is Myreth-5 Carboxylic Acid in beauty products?
Myreth-5 carboxylic acid is a man-made cleansing ingredient often found in face washes and shampoos. It helps lift dirt and oil from your skin so they can be rinsed away, but it's designed to be much gentler than old-fashioned soaps that can leave your skin feeling tight and dry. Think of it as a mild, hardworking helper that gets your skin clean without overdoing it.
What does Myreth-5 Carboxylic Acid do in a beauty product?
In a cosmetic product, myreth-5 carboxylic acid works by reducing the surface tension between water and oil, allowing oily dirt and makeup to be emulsified and rinsed away. Its carboxylic acid group gives it a slightly negative charge, which helps it interact gently with skin proteins, minimizing irritation compared to harsher sulfates.
Is Myreth-5 Carboxylic Acid safe for most people?
Myreth-5 carboxylic acid is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for sensitive skin. As with any ingredient, individual reactions are possible, but it is well-tolerated by most people.
Who should be careful with Myreth-5 Carboxylic Acid?
Individuals seeking 100% natural or organic-only ingredients
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.