Ingredient review
Potassium Trideceth-15 Carboxylate
INCI: POTASSIUM TRIDECETH-15 CARBOXYLATE
A gentle, effective surfactant that cleanses without over-drying, making it a good choice for sensitive or dry skin.
In plain English
Potassium Trideceth-15 Carboxylate is a mild soap-like ingredient that helps water mix with oil and dirt so they can be rinsed away. It is made from fatty acids (from natural oils) and ethylene oxide, a process that creates a very gentle cleanser. Unlike harsher soaps, it cleans without stripping your skin's natural moisture barrier, leaving it feeling soft rather than tight or dry.
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
- semi synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Potassium Trideceth-15 Carboxylate 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 Potassium Trideceth-15 Carboxylate.
- 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 semi-synthetic surfactant (cleansing agent) belonging to the carboxylate family. It is created by reacting a fatty alcohol (trideceth) with ethylene oxide and then converting it to a potassium salt. This structure gives it excellent water solubility and mildness.
How it works
It works by reducing the surface tension between water and oil, allowing oily dirt, sebum, and makeup to be lifted from the skin and suspended in water so they can be rinsed away. Its large molecular structure makes it less penetrating and less irritating than smaller surfactants.
Pros
Very gentle on skin
Its large molecular structure means it doesn't penetrate deeply, reducing irritation and making it ideal for sensitive or compromised skin barriers.
Leaves skin feeling soft
Unlike many sulfates, it doesn't strip natural oils, so your skin feels hydrated and comfortable after washing, not tight or dry.
Cons and cautions
Limited heavy-duty cleansing
It may struggle to fully remove heavy waterproof makeup or long-wear sunscreen without a double-cleansing step.
Potential eye sting at high levels
In high concentrations (above 10%), it can cause mild eye irritation, so it's best used in rinse-off products.
Best for
- People with dry or sensitive skin who find traditional cleansers too harsh
- Anyone looking for a gentle, non-stripping daily cleanser
Use caution if
- Those with known allergies to ethylene oxide derivatives (rare)
Usage tips
Safety summary
Potassium Trideceth-15 Carboxylate is considered safe for use in cosmetics at typical concentrations. It has low skin irritation and sensitization potential, though eye contact should be avoided in high concentrations. No significant safety concerns have been reported in regulatory reviews.
Research notes
Studies on similar carboxylate surfactants show they are mild and well-tolerated. While specific research on this exact ingredient is limited, its chemical class is well-documented as safe and effective for gentle cleansing. The Cosmetic Ingredient Review (CIR) panel has reviewed related alkoxylated carboxylates and found them safe as used.
Common label clues
- Typical concentration
- 1–10% in rinse-off products; lower in leave-on formulas
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database. No concentration restrictions for rinse-off products.
- Common uses
- Facial cleansers, Body washes, Shampoos, Makeup removers
- Environmental note
- Biodegradable and generally considered low in aquatic toxicity, making it a preferred choice in green formulations.
Good to know
- It is often listed near the middle or end of ingredient lists, indicating moderate concentration.
- It is biodegradable and considered more environmentally friendly than some traditional surfactants.
Common questions
What is Potassium Trideceth-15 Carboxylate in beauty products?
Potassium Trideceth-15 Carboxylate is a mild soap-like ingredient that helps water mix with oil and dirt so they can be rinsed away. It is made from fatty acids (from natural oils) and ethylene oxide, a process that creates a very gentle cleanser. Unlike harsher soaps, it cleans without stripping your skin's natural moisture barrier, leaving it feeling soft rather than tight or dry.
What does Potassium Trideceth-15 Carboxylate do in a beauty product?
It works by reducing the surface tension between water and oil, allowing oily dirt, sebum, and makeup to be lifted from the skin and suspended in water so they can be rinsed away. Its large molecular structure makes it less penetrating and less irritating than smaller surfactants.
Is Potassium Trideceth-15 Carboxylate safe for most people?
Potassium Trideceth-15 Carboxylate is considered safe for use in cosmetics at typical concentrations. It has low skin irritation and sensitization potential, though eye contact should be avoided in high concentrations. No significant safety concerns have been reported in regulatory reviews.
Who should be careful with Potassium Trideceth-15 Carboxylate?
Those with known allergies to ethylene oxide derivatives (rare)
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.