Ingredient review
Sodium Dilaureth-4 Phosphate
INCI: Sodium Dilaureth-4 Phosphate
A gentle synthetic surfactant that helps cleanse without stripping the skin's natural moisture barrier.
In plain English
Sodium Dilaureth-4 Phosphate is a synthetic ingredient that helps water mix with oil and dirt so they can be rinsed away. It is considered a mild cleanser, meaning it is less likely to leave your skin feeling tight or dry compared to harsher soaps. You'll find it in many face washes and shampoos where it helps create a gentle lather and leaves skin feeling soft.
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
Sodium Dilaureth-4 Phosphate 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 Sodium Dilaureth-4 Phosphate.
- 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 phosphate ester surfactant derived from lauryl alcohol and ethylene oxide, neutralized with sodium. It is a synthetic compound designed to be a gentle cleansing and emulsifying agent.
How it works
It reduces the surface tension between water and oil, allowing oils and impurities on the skin or hair to be lifted away and rinsed off. Its mild nature means it cleanses without overly disrupting the skin's natural lipid barrier.
Pros
Mild on skin
Unlike harsher sulfates, this surfactant cleanses effectively without stripping the skin's natural oils, making it suitable for daily use.
Good for sensitive formulas
Its low irritation profile makes it a popular choice for gentle facial cleansers and baby products.
Cons and cautions
Synthetic production
It is made through chemical synthesis, which may be a turn-off for consumers seeking naturally derived or minimal-ingredient products.
Potential trace impurities
As an ethoxylated ingredient, it may contain trace levels of 1,4-dioxane if not properly purified, though reputable manufacturers ensure low levels.
Best for
- People with normal to combination skin looking for a mild daily cleanser
- Those who prefer synthetic but gentle surfactants over sulfate-based cleansers
Use caution if
- Individuals with known sensitivity to ethoxylated ingredients
Usage tips
Safety summary
Sodium Dilaureth-4 Phosphate is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any ethoxylated ingredient, quality control is important to minimize trace impurities.
Research notes
Research on phosphate ester surfactants indicates they are mild and effective cleansers. The Cosmetic Ingredient Review has assessed similar ingredients and found them safe for cosmetic use. No significant safety concerns have been raised in peer-reviewed literature.
Common label clues
- Typical concentration
- 1-10% in rinse-off products
- Regulatory status
- Approved for use in cosmetics in the US, EU, and other major markets. The Cosmetic Ingredient Review (CIR) panel has reviewed similar phosphate esters and found them safe as used.
- Common uses
- Cleansers, Shampoos, Body washes, Facial washes
- Environmental note
- This ingredient is generally considered biodegradable, but its synthetic origin and ethoxylation process mean it has a higher environmental footprint than some naturally derived alternatives.
Good to know
- Sodium Dilaureth-4 Phosphate is often used in combination with other surfactants to improve foam quality and mildness.
- It is considered biodegradable and is commonly used in formulations that aim for a 'sulfate-free' label.
Common questions
What is Sodium Dilaureth-4 Phosphate in beauty products?
Sodium Dilaureth-4 Phosphate is a synthetic ingredient that helps water mix with oil and dirt so they can be rinsed away. It is considered a mild cleanser, meaning it is less likely to leave your skin feeling tight or dry compared to harsher soaps. You'll find it in many face washes and shampoos where it helps create a gentle lather and leaves skin feeling soft.
What does Sodium Dilaureth-4 Phosphate do in a beauty product?
It reduces the surface tension between water and oil, allowing oils and impurities on the skin or hair to be lifted away and rinsed off. Its mild nature means it cleanses without overly disrupting the skin's natural lipid barrier.
Is Sodium Dilaureth-4 Phosphate safe for most people?
Sodium Dilaureth-4 Phosphate is considered safe for use in cosmetics at typical concentrations. It has low irritation and comedogenic potential, making it suitable for most skin types. As with any ethoxylated ingredient, quality control is important to minimize trace impurities.
Who should be careful with Sodium Dilaureth-4 Phosphate?
Individuals with known sensitivity to ethoxylated 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.