Ingredient review
Myreth-5
INCI: MYRETH-5
Myreth-5 is a gentle synthetic cleanser that helps products foam and rinse cleanly, but it may not suit those avoiding ethoxylated ingredients.
In plain English
Myreth-5 is a man-made ingredient that helps cleansers and shampoos mix oil and water so they can wash away dirt and oil without stripping your skin. It's considered milder than some traditional sulfates, but it's made through a process called ethoxylation, which some people prefer to avoid due to trace impurity concerns.
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 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.
- 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 is a polyethylene glycol (PEG) ether of myristyl alcohol, a fatty alcohol derived from coconut or palm oil. It belongs to the alkyl ether sulfate family and is produced by reacting myristyl alcohol with 5 moles of ethylene oxide.
How it works
In a cosmetic product, Myreth-5 acts as a surfactant and emulsifier. Its water-loving and oil-loving ends allow it to surround dirt and oil particles, lift them from the skin or hair, and rinse them away with water. It also helps stabilize mixtures of oil and water in creams and lotions.
Pros
Mild on skin
Myreth-5 is less irritating than many traditional sulfates like sodium lauryl sulfate, making it a good choice for daily cleansing.
Good foam quality
It produces a rich, creamy lather that feels pleasant and helps distribute the product evenly over skin or hair.
Cons and cautions
Ethoxylation concerns
As a PEG compound, Myreth-5 may contain trace amounts of 1,4-dioxane, a potential carcinogen. Reputable manufacturers purify it to low levels, but it's a consideration for sensitive consumers.
Not natural
Myreth-5 is fully synthetic, which may not align with clean-beauty or natural-product preferences.
Best for
- People with normal to combination skin looking for a mild cleanser
- Those who want a sulfate-free alternative in shampoos and body washes
Use caution if
- Individuals who strictly avoid PEG compounds or ethoxylated ingredients due to personal preference or sensitivity
Usage tips
Safety summary
Myreth-5 is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential for trace 1,4-dioxane contamination, which is regulated and minimized by quality manufacturers. It has low irritation and comedogenic potential.
Research notes
PEG alkyl ethers like Myreth-5 have been reviewed by the Cosmetic Ingredient Review (CIR) panel and deemed safe for cosmetic use. Studies indicate low acute toxicity and skin irritation. Research on 1,4-dioxane contamination focuses on manufacturing purity rather than the ingredient itself.
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 US, EU, and many other regions. The Cosmetic Ingredient Review (CIR) panel has reviewed PEG alkyl ethers and found them safe as used, with the caveat that manufacturers should minimize 1,4-dioxane content.
- Common uses
- Cleansers, Shampoos, Body washes, Conditioners
- Environmental note
- Myreth-5 is derived from palm or coconut oil, which may raise sustainability concerns depending on sourcing. Look for brands that use certified sustainable palm oil.
Good to know
- Myreth-5 is often listed as 'Myreth-5' or 'PEG-5 Myristyl Ether' on ingredient labels.
- The number '5' indicates the average number of ethylene oxide units, which affects its solubility and mildness.
Common questions
What is Myreth-5 in beauty products?
Myreth-5 is a man-made ingredient that helps cleansers and shampoos mix oil and water so they can wash away dirt and oil without stripping your skin. It's considered milder than some traditional sulfates, but it's made through a process called ethoxylation, which some people prefer to avoid due to trace impurity concerns.
What does Myreth-5 do in a beauty product?
In a cosmetic product, Myreth-5 acts as a surfactant and emulsifier. Its water-loving and oil-loving ends allow it to surround dirt and oil particles, lift them from the skin or hair, and rinse them away with water. It also helps stabilize mixtures of oil and water in creams and lotions.
Is Myreth-5 safe for most people?
Myreth-5 is considered safe for use in cosmetics at typical concentrations. The main safety consideration is the potential for trace 1,4-dioxane contamination, which is regulated and minimized by quality manufacturers. It has low irritation and comedogenic potential.
Who should be careful with Myreth-5?
Individuals who strictly avoid PEG compounds or ethoxylated ingredients due to personal preference or sensitivity
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.