Ingredient review
Perfluorononylethyl Carboxydecyl Behenyl Dimethicone
INCI: PERFLUORONONYLETHYL CARBOXYDECYL BEHENYL DIMETHICONE
A high-performance synthetic ingredient that helps makeup and sunscreen stay put, but its environmental persistence raises concerns.
In plain English
This is a man-made molecule that combines silicone and fluorocarbon parts. It spreads easily on skin, feels silky, and forms a water-resistant film. Think of it as a super-slick coating that helps makeup last longer and keeps sunscreen from washing off. However, because it contains fluorinated components, it may not break down easily in the environment.
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
Perfluorononylethyl Carboxydecyl Behenyl Dimethicone 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 Perfluorononylethyl Carboxydecyl Behenyl Dimethicone.
- 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 synthetic hybrid polymer that combines a silicone backbone (dimethicone) with a fluorinated side chain (perfluorononylethyl) and a long-chain fatty group (behenyl). It is designed to create a durable, water-repellent film on the skin.
How it works
When applied, the ingredient spreads into a thin, even layer. The fluorinated part repels water and oil, while the silicone part gives a smooth, non-greasy feel. This film helps lock in other ingredients and prevents them from smudging or washing away.
Pros
Excellent water resistance
Forms a durable film that helps sunscreen and makeup stay effective even when you sweat or get wet.
Smooth, silky feel
Spreads easily and leaves a non-greasy, velvety finish that many people find pleasant on the skin.
Cons and cautions
Environmental persistence
The fluorocarbon part is not easily biodegradable, which raises concerns about accumulation in water and soil.
Limited skin safety data
While generally considered low-irritation, there is not a lot of independent research on how much of this ingredient absorbs through skin over time.
Best for
- People who want long-wearing, waterproof makeup or sunscreen
- Those with oily skin who prefer a matte, silky finish
Use caution if
- Individuals concerned about environmental persistence of fluorinated chemicals
Usage tips
Safety summary
Generally considered safe for topical use at typical concentrations. Low irritation and comedogenic risk. The main concern is environmental persistence rather than direct skin toxicity.
Research notes
Limited peer-reviewed studies specifically on this ingredient. Most safety data comes from broader silicone and fluorocarbon research. Industry sources support its low irritation profile.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US, EU, and many other regions. However, some fluorinated compounds are under review for environmental impact.
- Common uses
- Long-wear foundations, Waterproof sunscreens, Eye makeup, Lip products
- Environmental note
- Fluorinated silicones like this one are not readily biodegradable and may contribute to persistent environmental pollutants. Eco-conscious consumers may prefer alternatives.
Good to know
- This ingredient is often found in 'transfer-proof' or '24-hour wear' makeup formulas.
- It is not water-soluble, so you may need an oil-based cleanser to remove it fully.
Common questions
What is Perfluorononylethyl Carboxydecyl Behenyl Dimethicone in beauty products?
This is a man-made molecule that combines silicone and fluorocarbon parts. It spreads easily on skin, feels silky, and forms a water-resistant film. Think of it as a super-slick coating that helps makeup last longer and keeps sunscreen from washing off. However, because it contains fluorinated components, it may not break down easily in the environment.
What does Perfluorononylethyl Carboxydecyl Behenyl Dimethicone do in a beauty product?
When applied, the ingredient spreads into a thin, even layer. The fluorinated part repels water and oil, while the silicone part gives a smooth, non-greasy feel. This film helps lock in other ingredients and prevents them from smudging or washing away.
Is Perfluorononylethyl Carboxydecyl Behenyl Dimethicone safe for most people?
Generally considered safe for topical use at typical concentrations. Low irritation and comedogenic risk. The main concern is environmental persistence rather than direct skin toxicity.
Who should be careful with Perfluorononylethyl Carboxydecyl Behenyl Dimethicone?
Individuals concerned about environmental persistence of fluorinated chemicals
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.