What Actually Replaces HEMA in a HEMA-Free Gel?
"HEMA-free" does not mean "acrylate-free". HEMA has been swapped for other reactive acrylate monomers — not removed from the category. The industry moved from small, fast-penetrating molecules to larger, slower ones.
- The five common replacements are HPMA, Di-HEMA TMHDC, IBOMA, IBOA and HDDA.
- All five are reactive acrylates. All five are sensitisers in their uncured form.
- Bigger molecules cross skin more slowly. That is real progress — not zero risk.
Every stand at every trade show now prints "HEMA-free" in confident type. Almost none of them tell you what took its place. So let us name the molecules, in the exact form you will see them on an ingredient label: Hydroxyethyl Methacrylate (HEMA) is most often replaced by Hydroxypropyl Methacrylate (HPMA), Di-HEMA Trimethylhexyl Dicarbamate (Di-HEMA TMHDC), Isobornyl Methacrylate (IBOMA), Isobornyl Acrylate (IBOA) and Hexanediol Diacrylate (HDDA).
Pick up a bottle from your trolley and read the back. You will find at least one of them.
From here on I will use the short forms to keep this readable — but those are the words to look for on the label.
What HEMA actually does in a gel
You cannot understand why removing HEMA is complicated until you understand why it was used so heavily in the first place.
HEMA is a small, reactive monomer that does four jobs at once. It wets the surface of the nail plate so product flows and grips. It thins the formula to a workable viscosity. It takes part in the curing reaction. And it is a highly effective adhesion promoter.
For a formulator that is an extremely convenient molecule. It is also cheap.
Why the thing that makes it good is the thing that makes it risky
HEMA is small and mobile. Small molecules cross skin far more easily than large ones.
If HEMA reaches your skin — through overflow at the cuticle, a smear on a sidewall, a microdrop you never saw, or undercured product being filed off — it can sensitise you.
And once you are sensitised, it is permanent. No recovery. No tolerance built up over time. No desensitising course. Cross-reactivity to other acrylates is common, so the allergy rarely stays confined to the product that caused it.
For a technician doing dozens of sets a week, that is not an inconvenience. That is the end of a career.
The five replacements — what each one is doing
There is no single HEMA replacement. Formulators use a combination, each doing part of what HEMA did on its own.
On your label as: Hydroxypropyl Methacrylate
The closest structural relative to HEMA, and by far the most common substitution. One extra carbon group makes it slightly larger, so it penetrates skin a little more slowly. Still a reactive acrylate monomer. Still classified as a potential sensitiser uncured. A meaningful step — not a removal of risk.
On your label as: Di-HEMA Trimethylhexyl Dicarbamate
A much larger di-functional urethane methacrylate, favoured in rubber bases and builder gels. Its size means it penetrates skin far more slowly than HEMA. Sensitisation cases have still been documented. There is no zero-risk monomer.
On your label as: Isobornyl Methacrylate / Isobornyl Acrylate
Bulky, rigid monomers derived from isoborneol. They contribute hardness and durability, and are common in colour gel polish and hard gels. The larger structure reduces skin penetration. Sensitisation potential uncured remains.
On your label as: Hexanediol Diacrylate
A di-functional acrylate crosslinker that ties the polymer network together for durability and hardness. It carries a relatively higher skin sensitisation potential than the others listed here. Its presence in a formula should not be overlooked.
Notice the pattern
Every single one of those is a reactive acrylate.
The shift has been from small molecules to bigger ones. That genuinely reduces how fast a molecule can cross your skin, and it is worth having. But it is not a move away from acrylate chemistry, and it is not a reason to relax about product touching skin.
The vast majority of HEMA-free products still contain reactive acrylate monomers. That is the honest summary.
A product can print "HEMA-free" on the front and still contain HEMA — legally, and with nothing on the ingredient list to warn you. That is Part 2 of this series.
Common questions
Is HEMA-free gel polish safe for everyone?
No. HEMA-free products still contain reactive acrylate monomers such as HPMA, IBOA, IBOMA or HDDA, all of which can sensitise skin in their uncured form. HEMA-free reduces one specific risk. It does not eliminate acrylate allergy risk.
Is HEMA banned in the EU?
No. Since 3 September 2021, under Regulation (EU) 2020/1682, HEMA and Di-HEMA TMHDC are restricted to nail products for professional use only, and must be labelled "For professional use only" and "Can cause an allergic reaction". Consumer sale was stopped. Professional use was not.
The HEMA-Free series
- Part 1 — What actually replaces HEMA (you are here)
- Part 2 — The HEMA hiding inside "HEMA-free"
- Part 3 — Why so many gels feel identical
- Part 4 — It is not the ingredient, it is the cure
- Part 5 — How to judge a gel system
References
- Commission Regulation (EU) 2020/1682 of 12 November 2020 amending Annex III to Regulation (EC) No 1223/2009 — restricting HEMA and Di-HEMA TMHDC to professional nail products. eur-lex.europa.eu
- Scientific Committee on Consumer Safety (SCCS). Opinion on the safety of cosmetic ingredients HEMA and Di-HEMA Trimethylhexyl Dicarbamate, SCCS/1592/17, final version adopted June 2018. health.ec.europa.eu
Questions about what is on your own labels? Email help@ikoniqnails.com, WhatsApp +49 160 649 7218, or use our contact form.
Written by Robert Giblett, Founder & CEO of IKON.IQ®.
