Ingredient review
Perfluorononylethyl Carboxydecyl PEG-8 Dimethicone
INCI: PERFLUORONONYLETHYL CARBOXYDECYL PEG-8 DIMETHICONE
A specialized silicone-fluorocarbon hybrid that helps products spread smoothly and resist water, but its environmental persistence raises concerns.
In plain English
This ingredient is a man-made molecule that combines silicone and fluorocarbon parts. In skincare, it helps other ingredients spread evenly on the skin and forms a light, water-resistant film. Think of it as a helper that makes your makeup last longer or your sunscreen stay on better when you sweat. However, because it contains fluorocarbon (a type of PFAS), it does not break down easily in the environment, which is a growing concern for many consumers.
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 PEG-8 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 PEG-8 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 molecule that joins a perfluorinated chain (fluorocarbon) with a silicone (dimethicone) backbone, modified with PEG (polyethylene glycol) groups to make it water-dispersible.
How it works
It lowers the surface tension between oil and water phases in a formula, helping ingredients mix and spread. Once applied, it dries down into a flexible, water-resistant film that can lock in other ingredients or improve wear time.
Pros
Excellent spreadability
Helps creams and lotions glide on smoothly without a sticky or greasy feel.
Water-resistant film
Forms a light barrier that helps makeup and sunscreen stay put longer, even in humid conditions.
Cons and cautions
Environmental concerns
As a fluorinated compound, it is part of the PFAS family and does not readily break down in nature, raising eco-toxicity questions.
Limited natural alternatives
If you prefer plant-based or biodegradable ingredients, this synthetic hybrid won't fit your routine.
Best for
- People who want long-wearing makeup or water-resistant sunscreen
- Those with normal to oily skin looking for a non-greasy finish
Use caution if
- Consumers avoiding PFAS or synthetic ingredients for environmental reasons
- Those with very sensitive or reactive skin (though irritation risk is low)
Usage tips
Safety summary
Generally recognized as safe for topical use at typical concentrations, with low irritation and comedogenic potential. However, its classification as a PFAS raises environmental and potential long-term health concerns that are still under study.
Research notes
Limited peer-reviewed studies specifically on this ingredient. Broader research on PFAS indicates environmental persistence and potential bioaccumulation, but dermal absorption of large-molecule fluorosilicones is considered low.
Common label clues
- Typical concentration
- 0.5% to 5%
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng), but regulatory scrutiny of PFAS is increasing globally. Some regions are considering restrictions.
- Common uses
- Cleansers, Makeup removers, Water-resistant sunscreens, Long-wear foundations
- Environmental note
- Fluorinated silicones like this one are highly persistent in the environment and may accumulate in water and soil. They are not biodegradable.
Good to know
- This ingredient is often found in 'long-wear' or 'waterproof' labeled cosmetics.
- It is considered a PFAS (per- and polyfluoroalkyl substance) due to its fluorocarbon tail.
Common questions
What is Perfluorononylethyl Carboxydecyl PEG-8 Dimethicone in beauty products?
This ingredient is a man-made molecule that combines silicone and fluorocarbon parts. In skincare, it helps other ingredients spread evenly on the skin and forms a light, water-resistant film. Think of it as a helper that makes your makeup last longer or your sunscreen stay on better when you sweat. However, because it contains fluorocarbon (a type of PFAS), it does not break down easily in the environment, which is a growing concern for many consumers.
What does Perfluorononylethyl Carboxydecyl PEG-8 Dimethicone do in a beauty product?
It lowers the surface tension between oil and water phases in a formula, helping ingredients mix and spread. Once applied, it dries down into a flexible, water-resistant film that can lock in other ingredients or improve wear time.
Is Perfluorononylethyl Carboxydecyl PEG-8 Dimethicone safe for most people?
Generally recognized as safe for topical use at typical concentrations, with low irritation and comedogenic potential. However, its classification as a PFAS raises environmental and potential long-term health concerns that are still under study.
Who should be careful with Perfluorononylethyl Carboxydecyl PEG-8 Dimethicone?
Consumers avoiding PFAS or synthetic ingredients for environmental reasons Those with very sensitive or reactive skin (though irritation risk is low)
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.