What Is Undeceth-3?
Undeceth-3 is a synthetic ingredient made by linking three small units of ethylene oxide to undecyl alcohol, an 11-carbon fatty alcohol that can come from either petroleum or plant oils. This gives it the full name Polyethylene Glycol (3) Undecyl Ether. Chemists began using similar nonionic surfactants in the 1960s when they were searching for mild cleansing agents that mixed well with water and oils. To produce Undeceth-3, manufacturers run undecyl alcohol through a controlled ethoxylation process, adding exactly three ethylene oxide units to create a clear, water-soluble liquid. Because it can soften skin, lift away dirt and help water blend with oils, you will often find it in facial cleansers, body washes, shampoos, makeup removers, lightweight lotions, sunscreens and anti aging serums.
Undeceth-3’s Cosmetic Benefits/Uses
Formulators like Undeceth-3 because it can play more than one helpful role in a single product.
- Skin conditioning: Leaves a light, soft feel on the surface so skin feels smoother after rinsing or drying
- Emollient: Adds a thin protective layer that helps hold moisture in and reduces rough, dry patches
- Cleansing: Acts as a gentle surfactant that loosens dirt, oil and makeup so they wash away easily
- Emulsifying: Helps water and oil based ingredients stay mixed, keeping creams and lotions stable and uniform
Who Can Use Undeceth-3
Undeceth-3 is generally considered suitable for most skin types, including normal, oily and combination, because it is a mild nonionic surfactant that rinses clean without leaving a heavy residue. People with very dry or highly sensitive skin should still check the full product formula since high levels of any cleanser can sometimes feel stripping if the item is not balanced with other moisturising agents.
The ingredient itself is synthetic and can be made from either plant-derived or petroleum-based sources, not from animals, so it is usually acceptable for vegans and vegetarians. If animal-free sourcing is important to you, verify that the finished product states it is vegan certified.
No published data link topical Undeceth-3 to problems for women who are pregnant or breastfeeding. Current safety reviews have not flagged it as an endocrine disruptor or reproductive toxin, so products containing it are generally viewed as low risk. This is not medical advice and anyone who is pregnant or nursing should show the full ingredient list of any skincare product to a healthcare professional before use.
Undeceth-3 does not increase photosensitivity, so it will not make skin more prone to sunburn. It is also non-comedogenic by itself and has no known interactions with leave-on actives such as vitamin C or retinoids.
Potential Side Effects/Adverse Reactions
Reactions to topical Undeceth-3 vary from person to person. The issues listed below are only potential side effects and are unlikely for most users when the ingredient is used at the levels normally found in cosmetics.
- Transient skin dryness or tightness after rinsing if the overall formula lacks moisturisers
- Mild stinging or redness on very sensitive or compromised skin
- Rare allergic contact dermatitis presenting as itching or rash
- Eye irritation if a cleanser containing Undeceth-3 accidentally gets into the eyes
- Possible trace contamination with 1,4-dioxane if the manufacturer does not properly purify the ingredient, though reputable suppliers keep levels far below safety thresholds
If you notice irritation, redness or any persistent discomfort while using a product containing Undeceth-3 stop using it and seek advice from a medical professional.
Comedogenic Rating
Rating: 0 / 5
Undeceth-3 is a water-soluble nonionic surfactant that rinses clean without leaving an oily film that could block pores. Its molecular structure is designed to lift away sebum rather than sit on the skin, so it is considered non-comedogenic
Because of this, products containing Undeceth-3 are generally suitable for people who are prone to acne or breakouts
Like most cleansing agents its behavior can change when combined with heavy oils or waxes, so the finished formula, not the single ingredient, ultimately determines pore-clogging potential
Summary
Undeceth-3 acts as a skin conditioner, emollient, gentle cleanser and emulsifier. The three ethylene oxide units on its backbone let it mix water with oil while the undecyl chain leaves a light smoothing feel, so it can soften skin, remove dirt and keep creams stable all at once
It pops up most often in face washes, micellar waters and lightweight lotions. It is not as famous as ingredients like glycerin or hyaluronic acid yet formulators value it for its multitasking nature and mildness
Current safety data show low irritation risk, no evidence of sensitization and negligible contamination when the raw material is properly purified. Even so it is wise to patch test any new product containing Undeceth-3 to be sure your skin agrees with the full blend