Ingredient review
Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer
INCI: ACETYLENEDIUREA/FORMALDEHYDE/TOSYLAMIDE CROSSPOLYMER
A synthetic polymer that helps products last longer and feel smooth, but its formaldehyde component raises some safety questions.
In plain English
This ingredient is a plastic-like substance made by linking several chemicals together. In cosmetics, it forms a thin, flexible film on skin, hair, or nails. Think of it like a clear, invisible coating that helps makeup stay put or nail polish resist chipping. It's not absorbed into the skin in any meaningful way.
Quick decision guide
Read the cautions before using
Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer 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 Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer.
- 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 crosslinked polymer created from acetylenediurea, formaldehyde, and tosylamide. It is a synthetic resin designed to form a durable, flexible film on surfaces.
How it works
When applied, the polymer chains spread out and then dry into a continuous film. This film acts as a barrier, locking in color and texture while resisting water, oil, and friction. It also thickens the product slightly, making it easier to apply evenly.
Pros
Long-lasting wear
Creates a durable film that helps nail polish and makeup resist chipping, smudging, and fading throughout the day.
Smooth application
Improves the texture of products, making them glide on evenly and dry to a uniform, glossy finish.
Cons and cautions
Formaldehyde concern
Formaldehyde is used in its production. While residual levels are tightly controlled, it may still be a concern for sensitive individuals.
Not eco-friendly
As a synthetic polymer, it does not break down easily in the environment and may contribute to plastic pollution.
Best for
- People who want long-lasting nail polish or makeup
- Those looking for a smooth, chip-resistant finish
Use caution if
- Individuals with known formaldehyde allergy or sensitivity
- Those seeking fully natural or biodegradable products
Usage tips
Safety summary
Generally considered safe for topical use at typical concentrations. The formaldehyde used in synthesis is chemically bound and present only in trace amounts, but individuals with formaldehyde allergies should exercise caution.
Research notes
Limited peer-reviewed studies specifically on this polymer. Safety assessments rely on general polymer toxicology and formaldehyde exposure limits. Industry data supports its safety as a film former.
Common label clues
- Typical concentration
- Typically 1–10% in nail products; lower in leave-on cosmetics
- Regulatory status
- Approved for use in cosmetics in the US (FDA) and EU (CosIng) with no specific concentration limits, though formaldehyde content is regulated as a contaminant.
- Common uses
- Nail polishes, Long-wear makeup, Hair styling products
- Environmental note
- This polymer is not biodegradable and may persist in water systems. It is not known to bioaccumulate significantly.
Good to know
- This ingredient is most commonly found in nail polish and long-wear lip products.
- Regulatory bodies like the EU CosIng database list it as a film former with no specific restrictions at typical use levels.
Common questions
What is Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer in beauty products?
This ingredient is a plastic-like substance made by linking several chemicals together. In cosmetics, it forms a thin, flexible film on skin, hair, or nails. Think of it like a clear, invisible coating that helps makeup stay put or nail polish resist chipping. It's not absorbed into the skin in any meaningful way.
What does Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer do in a beauty product?
When applied, the polymer chains spread out and then dry into a continuous film. This film acts as a barrier, locking in color and texture while resisting water, oil, and friction. It also thickens the product slightly, making it easier to apply evenly.
Is Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer safe for most people?
Generally considered safe for topical use at typical concentrations. The formaldehyde used in synthesis is chemically bound and present only in trace amounts, but individuals with formaldehyde allergies should exercise caution.
Who should be careful with Acetylenediurea/Formaldehyde/Tosylamide Crosspolymer?
Individuals with known formaldehyde allergy or sensitivity Those seeking fully natural or biodegradable products
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.