Ingredient review
Trideceth-20
INCI: Trideceth-20
A gentle, water-soluble surfactant that helps cleanse without stripping the skin’s natural moisture barrier.
In plain English
Trideceth-20 is a mild cleansing ingredient that helps water and oil mix together so dirt and makeup can be rinsed away easily. It is often used in gentle cleansers and shampoos because it cleans without leaving skin feeling 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
Trideceth-20 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 Trideceth-20.
- 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
Trideceth-20 is a semi-synthetic surfactant made by reacting tridecyl alcohol (a fatty alcohol from natural sources) with about 20 units of ethylene oxide. This process makes it water-soluble and gentle on skin.
How it works
It reduces the surface tension between water and oil, allowing them to blend. This helps lift dirt, sebum, and makeup from the skin so they can be washed away with water. Its mild nature means it doesn’t strip the skin’s protective oils.
Pros
Very gentle on skin
Unlike stronger sulfates, Trideceth-20 cleans without stripping natural oils, making it suitable for daily use on sensitive or dry skin.
Versatile in formulations
It works well in both rinse-off and leave-on products, helping to blend oils and water for a smooth, stable texture.
Cons and cautions
Semi-synthetic origin
It is made using ethylene oxide, a process that raises environmental and purity concerns, though the final ingredient is considered safe in approved concentrations.
Not natural
If you prefer plant-based or naturally derived ingredients, Trideceth-20 may not align with that preference.
Best for
- People with normal to dry skin who want a gentle cleanser
- Those with sensitive skin who react to harsher sulfates
Use caution if
- Individuals seeking 100% natural or organic skincare
- Those with known sensitivity to PEG compounds (rare)
Usage tips
Safety summary
Trideceth-20 is considered safe for cosmetic use at typical concentrations. It has low irritation and comedogenic potential. As with all PEG compounds, purity is important to avoid contamination with 1,4-dioxane, but reputable manufacturers ensure this is minimized.
Research notes
The Cosmetic Ingredient Review (CIR) panel reviewed PEG alkyl ethers and found them safe for use in cosmetics. No significant human or animal studies indicate toxicity at typical exposure levels.
Common label clues
- Typical concentration
- 1–10% in rinse-off products; lower in leave-on formulations
- Regulatory status
- Approved for use in cosmetics by the FDA and EU CosIng database. The Cosmetic Ingredient Review (CIR) panel has deemed it safe in current usage concentrations.
- Common uses
- Cleansers, Shampoos, Body washes, Makeup removers
- Environmental note
- While the ingredient itself is biodegradable, the manufacturing process involves ethylene oxide, which requires careful handling to minimize environmental impact.
Good to know
- Trideceth-20 is often used in baby shampoos because of its mildness.
- It is considered biodegradable under standard wastewater treatment conditions.
Common questions
What is Trideceth-20 in beauty products?
Trideceth-20 is a mild cleansing ingredient that helps water and oil mix together so dirt and makeup can be rinsed away easily. It is often used in gentle cleansers and shampoos because it cleans without leaving skin feeling tight or dry.
What does Trideceth-20 do in a beauty product?
It reduces the surface tension between water and oil, allowing them to blend. This helps lift dirt, sebum, and makeup from the skin so they can be washed away with water. Its mild nature means it doesn’t strip the skin’s protective oils.
Is Trideceth-20 safe for most people?
Trideceth-20 is considered safe for cosmetic use at typical concentrations. It has low irritation and comedogenic potential. As with all PEG compounds, purity is important to avoid contamination with 1,4-dioxane, but reputable manufacturers ensure this is minimized.
Who should be careful with Trideceth-20?
Individuals seeking 100% natural or organic skincare Those with known sensitivity to PEG compounds (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.