What Is Triceteareth-4 Phosphate?
Triceteareth-4 Phosphate is a lab-made ingredient created by attaching about four units of ethylene oxide to long-chain fatty alcohols that come from coconut or palm oil, then adding a small amount of phosphate. This mix of oil-loving and water-loving parts lets it sit at the border between oil and water, which is why chemists call it a surfactant. Similar polyethylene glycol surfactants have been used in soaps and creams since the 1960s, and the phosphate version gained traction in the late 1980s when brands looked for milder, more versatile cleansers.
Manufacturers start with cetyl and stearyl alcohol, add ethylene oxide in a controlled reaction, then treat the result with phosphoric acid to lock in the phosphate group. The finished material is usually a clear to pale yellow liquid or soft paste that blends quickly in water or oils.
You will most often spot Triceteareth-4 Phosphate in face washes, micellar waters, makeup removers, liquid foundations, moisturizers, sheet masks, leave-on hair conditioners and wet wipes where a gentle cleanse or stable oil-in-water mix is needed.
Triceteareth-4 Phosphate’s Cosmetic Benefits/Uses
The ingredient earns its place on an ingredient list because it can perform more than one job at once.
- Cleansing: Its surfactant nature lifts away dirt, excess oil and makeup without leaving skin tight or squeaky. This makes formulas feel mild yet effective, boosting the user’s perception of a gentle cleanse.
- Emulsifying: It holds oil and water phases together so creams, lotions and liquid makeup stay smooth and uniform from the factory to the bathroom shelf. A stable emulsion spreads evenly, delivers actives consistently and resists separating in hot or cold weather.
This surfactant–emulsifier is generally considered suitable for all skin types including dry, oily, combination and sensitive skin because it is mild and typically used at low percentages. Those with very reactive or compromised barriers should still keep an eye on how their skin feels, as any new ingredient can occasionally trigger irritation.
Triceteareth-4 Phosphate is synthesized from plant-derived fatty alcohols and petroleum-sourced ethylene oxide, with no animal by-products involved, so products that use it are normally vegan and vegetarian friendly. Always confirm with the brand if animal testing or secondary animal ingredients appear elsewhere in the formula.
Current safety data reveal no specific risks for pregnant or breastfeeding women when this ingredient is applied topically in rinse-off or leave-on products. This is not medical advice and anyone who is pregnant or nursing should show the full product list to their healthcare provider for personalized guidance.
The molecule does not absorb UV light or make skin more sensitive to the sun, so it is not linked to photosensitivity. It is also fragrance-free, gluten-free and unlikely to interfere with actives like retinoids or vitamin C.
Potential Side Effects/Adverse Reactions
Side effects from topical Triceteareth-4 Phosphate can vary by individual. The points below outline potential reactions, although most people will not experience them when the ingredient is used correctly in a finished cosmetic.
- Mild skin irritation such as redness, stinging or tightness, particularly on already inflamed or broken skin
- Contact dermatitis in rare cases for those with an existing sensitivity to polyethylene glycol derivatives or phosphate esters
- Eye irritation if a high-foaming cleanser containing the ingredient gets into the eyes
If any of these reactions occur discontinue use and consult a qualified healthcare professional.
Comedogenic Rating
Rating: 1/5
Triceteareth-4 Phosphate is highly water soluble and used at low levels, so it rinses clean without leaving a heavy film that could clog pores. Its ethoxylated structure reduces the oily nature of the original fatty alcohols, making it far less likely to trap sebum or dead skin inside follicles. For these reasons it earns a low score of 1.
Given the low rating this ingredient is generally suitable for people who are prone to acne or frequent breakouts.
No comedogenic testing specific to this molecule has been published, but data on similar PEG surfactants support its low-risk profile.
Summary
Triceteareth-4 Phosphate is a multitasking surfactant that lifts away dirt and makeup while also acting as an emulsifier that keeps oil and water blended in creams, lotions and liquid cosmetics. It does this by positioning its water loving phosphate end in the aqueous phase and its fatty tail in the oil phase, lowering surface tension so the two stay mixed and the formula cleanses gently.
It is not the hottest buzzword on ingredient lists but formulators like it for its versatility and mildness, so you will notice it scattered across face washes, micellar waters, lightweight lotions and even some hair products.
Current research shows it is safe for topical use with only rare reports of irritation. As with any new skincare ingredient it is still wise to carry out a quick patch test before fully incorporating a product into your routine.