TPO, HEMA… These intimidating abbreviations were at the heart of debates about gel polish for years, before the substances were banned or strictly regulated in Europe. What risks do they pose, and how can you spot them to make sure your polish is TPO-free and HEMA-free? Here’s a practical guide to choosing your polish safely.
In short: which brand is TPO-free and HEMA-free?
- TPO, used as a photoinitiator in gel polish formulas, has been banned in the European Union since 1 September 2025 because of its toxic effects on reproduction.
- Methacrylate monomers (HEMA and Di-HEMA TMHDC) were long used as film-forming agents in gel polishes. Recognised as contact allergens, their use has been strictly limited to professionals since 2021.
- Before buying a new polish or booking a salon manicure, check the INCI list and look for the names of substances to avoid.
- Green Flash™ is a TPO-free and HEMA-free polish, using copolymers and TPO-L instead for a healthy manicure that doesn’t compromise on performance.
TPO and HEMA: two substances not to confuse
They’re often mentioned together, but these two substances play very different roles in gel polish formulas and have different regulatory statuses.
TPO: a CMR-classified photoinitiator banned in the EU
TPO (full name: Trimethylbenzoyl Diphenylphosphine Oxide) is a photoinitiator. What does that mean? It’s the ingredient that reacts to light from a UV or LED lamp and triggers the curing of the polish. Without a photoinitiator, there’s no curing: the gel polish stays liquid, and there’s no beautiful hard, glossy layer over the nail!
Under scrutiny by European health authorities for around a decade because of suspected reproductive toxicity, TPO was permitted in products at a maximum concentration of 5%. Since 1 September 2025 and the entry into force of European Regulation (EU) 2025/877, known as “Omnibus VII”, it has been banned in cosmetic products in the EU. Polish formulas containing it can no longer be:
- placed on the market ;
- made available, including to professionals;
- used in salons.
To understand this change, read our more detailed article on why TPO is banned in Europe.
HEMA: allergenic monomers that need careful handling
HEMA (hydroxyethyl methacrylate) and its relative Di-HEMA TMHDC are methacrylate monomers. These tiny, highly reactive molecules bond together under the lamp to form the familiar “gel” layer of a gel manicure.
These monomers are effective, but they can penetrate the skin, especially when polish gets on the cuticles or isn’t cured properly. This risk has also been identified in other sectors where HEMA is used and handled with appropriate protection, such as dentistry, plastics manufacturing and printing.
Since September 2021, European Regulation (EU) 2020/1682 has strictly regulated their use:
- Nail products containing them can no longer be sold to the general public.
- Their use is restricted to professionals.
- Their labels must carry two warnings: “For professional use only” and “Can cause an allergic reaction”.
👉 Key takeaway: polishes containing TPO are banned for everyone, while polishes containing HEMA are restricted to professionals under certain conditions of use (protective equipment, ventilation, etc.).
Why avoid TPO and HEMA?
Banned or regulated, yes… but not entirely gone from our drawers (or resale platforms). Here’s why it pays to stay vigilant:
TPO is classified as a category 1B CMR substance. In other words, its toxicity to human reproduction and embryonic development has been established, as confirmed by several toxicological studies and the Scientific Committee on Consumer Safety’s 2025 safety assessment.
☝ While TPO no longer has a place in any cosmetics sold in Europe, a bottle bought before September 2025 or outside the EU may contain it. So it’s worth checking your polishes! If an old bottle of gel polish lists “Trimethylbenzoyl Diphenylphosphine Oxide” among its ingredients, it’s best to dispose of it at a collection point rather than put it in the bin.
As for HEMA, these are contact allergens with a cumulative effect. Skin becomes sensitised with repeated applications, especially when polish gets on the cuticles or doesn’t cure properly (an unsuitable lamp or too little exposure time). And once an allergy develops, it’s hard to get rid of. There’s also the issue of removal. Monomer-based formulas are generally removed with acetone, along with buffing or filing, which weakens the nail plate.
👉 So if you’re getting a salon manicure and want a monomer-free polish, don’t hesitate to ask your nail technician about the ingredients in the products they use. A good professional should make a habit of checking their products’ INCI lists.
☝ Take care : a “HEMA-free” polish isn’t necessarily monomer-free. Some formulas simply replace HEMA with other methacrylates from the same family that are still permitted. That’s why it helps to know how to read a label. More on that below.
And if you want to know what steps to take every day, our guide to the least harmful nail polish is the perfect companion to this article.
How can you tell if a polish contains TPO or HEMA?
The good news: you don’t need a chemistry degree to tell them apart! Just read the INCI list.
Read the INCI list
The INCI list is the official list of ingredients in a product, required on all cosmetics sold in Europe. You’ll find it on the packaging, in the leaflet or on the online product page (much easier to read than the tiny lettering on a 15ml bottle, we’ll admit). Ingredients are listed in descending order of concentration, and each substance has a unique international name. That’s the name to look for, not the abbreviation!
💡 Good to know: If the label says “For professional use only” and “Can cause an allergic reaction”, that’s a sign the product very likely contains HEMA or Di-HEMA TMHDC.
The names to look for to avoid HEMA and TPO
Here are the molecule names to look for on INCI lists to make sure you’re buying a TPO-free and HEMA-free polish:
| 🧪 Name to look for | ⚖️ Status | ⚠️ Health risks | 🔀 Alternative | |
|---|---|---|---|---|
| TPO | Trimethylbenzoyl Diphenylphosphine Oxide | Banned in the EU since 1 September 2025 | Toxic to reproduction, classified as CMR-1B | TPO-L (Ethyl Trimethylbenzoyl Phenylphosphinate) |
| HEMA | HEMA (Hydroxyethyl Methacrylate) | Sale to the general public prohibited Restricted to professional use since 2021 |
Allergic dermatitis, breathing difficulties, asthma | Copolymers (Bis-HEMA Poly(1,4-Butanediol)-9/IPDI Copolymer) |
| Di-HEMA TMHDC | Di-HEMA Trimethylhexyl Dicarbamate | Sale to the general public prohibited Restricted to professional use since 2021 |
Allergic dermatitis, breathing difficulties, asthma | Copolymers (Bis-HEMA Poly(1,4-Butanediol)-9/IPDI Copolymer) |
Safe alternatives (TPO-L, copolymers)
Gel polish needs a photoinitiator and components that can cure under a lamp to form the solid, glossy layer you expect. The good news? Both of the problematic components we’ve just covered have safe alternatives:
- TPO-L (Ethyl Trimethylbenzoyl Phenylphosphinate): a safe, stable photoinitiator that is not classified as a CMR substance or endocrine disruptor and enables the polish to cure under an LED lamp.
- Copolymers (Bis-HEMA Poly(1,4-Butanediol)-9/IPDI Copolymer): chains of molecules that are larger than monomers and non-volatile. They have the same film-forming properties under an LED lamp but do not cross the skin barrier or cause allergic reactions.
Green Flash™, the TPO-free and HEMA-free polish
At Manucurist, we didn’t wait for regulations to sort through our ingredients (and we’re proud of it!). Since its creation, the brand has been committed to more responsible beauty, with formulas that are safe for your nails.
A pioneering brand, always ahead of the regulations
Launched in 2019 after more than a year of research, Green Flash™ gel polish was designed without HEMA or Di-HEMA TMHDC from the start, two years before the 2021 European regulation removed them from sale to the general public. The same goes for TPO: our lab ruled it out during the development of Green Flash™, long before its 2025 ban, choosing TPO-L instead. Behind every bottle is real research and development to:
- identify every potentially problematic ingredient and replace it with a safe alternative.
- replace petrochemical-derived components with ingredients derived from plant-based raw materials such as cassava, cotton, sugar cane, corn or wheat.
To discover what makes our formulas unique, dive into our article What makes Green Flash™ different? or our guide to the best bio-based gel polish.
A manicure without compromise
And the results? With Green Flash™, you get:
- A formula with up to 84% naturally derived ingredients, vegan and made in France.
- More than 120 nail polish shades, from everyday nudes to the boldest colours.
- A 3-step routine in one complete kit with Base Coat, colour, Top Coat and an LED lamp.
- Wear time of up to 12 days with Green Flash™ Top Coat or 21 days with Xtrem Flash™ Top Coat.
- No filing or acetone needed for removal in 1 to 2 minutes per hand with Green Flash™ Gentle Remover (allow 10 minutes for an Xtrem Flash™ manicure).
💡 Did you know? Because copolymers form a less dense network than conventional monomers, Green Flash™ removes gently, without scraping or filing the nail plate. Your natural nails stay beautiful, so you can enjoy a few days of perfect bare nails between manicures.
You’ve got it: to find a TPO-free and HEMA-free polish, the INCI list is your best guide. Look for the right names, avoid monomers and choose a brand that stayed ahead of the regulations rather than scrambling to catch up. With Green Flash™, you get the wear and shine of gel polish without compromising on care for your nails! Now you can read a label like a nail pro… over to you 💅✨!
