The TPO ban in gel polish: what changed in 2025

On 1 September 2025 the most common curing agent in gel nail polish became a prohibited substance across the European Union. Gels containing TPO could no longer be sold, and salons could no longer use them on clients, with no period to run down stock. Suppliers had reformulated through the summer, and by autumn TPO-free was a standard line on gel packaging.

The ban came from a classification rule, not from evidence that gel manicures had harmed anyone. That distinction explains most of the confusion since: why a substance the EU's own scientific committee once judged safe in nail products is now banned, why the UK chose later dates, and why a bottle in a bathroom cabinet is a different question from a bottle in a salon.

What is TPO and what does it do in gel polish?

TPO is diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, a photoinitiator: a molecule that absorbs UV and visible light and splits into reactive fragments that start the polymerisation of the acrylate monomers and oligomers in a gel polish. Under a 365 to 405 nm lamp it turns a liquid coat into a hard, cross-linked film in seconds. It was widely used because it absorbs across a broad range of wavelengths and yellows very little, which suits pale and clear gels⁴.

On an ingredient list TPO appears as Trimethylbenzoyl Diphenylphosphine Oxide. It has no role in solvent nail polish, which dries by evaporation and contains no monomer to cure. The ban therefore concerns gel polish, builder gels, gel top coats and some adhesives, and nothing in an ordinary bottle of lacquer.

Why did the EU ban TPO?

Under Article 15 of Regulation (EC) No 1223/2009, a substance classified as carcinogenic, mutagenic or toxic to reproduction (CMR) in category 1A or 1B is prohibited in cosmetics unless a narrow exception is granted. TPO was classified as toxic to reproduction category 1B, on the basis of animal data, by Commission Delegated Regulation (EU) 2024/197. Commission Regulation (EU) 2025/877 of 12 May 2025 then added it to Annex II of the cosmetics regulation as entry 1731, applicable from 1 September 2025¹.

The classification, not a new study of manicures, drove the ban. The EU's Scientific Committee on Consumer Safety had earlier found TPO safe in nail products at the concentrations used, and the Commission's guidance notes that those opinions predate the new classification and no longer apply unless updated². Category 1B means the substance is presumed to affect human reproduction based on animal evidence; category 1A would require human evidence.

Caroline Rainsford, director of science at the UK trade body CTPA, put the exposure in context: the amount used in nail products is more than a thousand times below the level at which any effect on fertility could occur⁴. The rule is precautionary by design, and it applies regardless of dose.

When did the ban take effect, and where?

The EU date is 1 September 2025 in all 27 member states, and the regulation also applies in Norway, Iceland and Liechtenstein through the European Economic Area. Switzerland aligned with it. The Commission is explicit that the cosmetics regulation contains no sell-through or use-up provision for CMR substances, so from that date all placing on the market and making available in the course of commercial activity had to stop, even for products already in stock or purchased before the date².

The Great Britain dates come from the Office for Product Safety and Standards' statutory instrument as reported by the trade press, with the two deadlines confirmed by CTPA⁵. The United States has no equivalent rule, and TPO gels remain on sale there⁶.

What should salons and nail technicians do?

In the EU, a salon may not use a TPO-containing gel on a client for payment, because that is making available in the course of commercial activity. Stock bought before 1 September 2025 cannot be used up or sold on. The practical steps are to check every gel, builder, top coat and adhesive in the salon against its ingredient list, withdraw anything listing Trimethylbenzoyl Diphenylphosphine Oxide, dispose of it as chemical waste, and reorder TPO-free versions from suppliers who state the change on the label or safety data sheet.

Two related checks belong in the same audit. Hydroxyethyl methacrylate (HEMA) and di-HEMA trimethylhexyl dicarbamate have been restricted to professional use since Commission Regulation (EU) 2020/1682, so any gel that contains them must carry For professional use only and Can cause an allergic reaction and must not be sold to clients for home use³. And a TPO-free reformulation may cure differently: many need a slightly longer cure or a lamp with the right wavelength, so technicians should follow the new product's instructions, not the old routine.

What should consumers do?

You will need: the bottle or box of any gel product you own, and the ingredient list on it or on the brand's website.

1. Read the ingredient list for Trimethylbenzoyl Diphenylphosphine Oxide. If it is absent, the product is unaffected by the ban.
2. If it is present and the product was bought in the EU after 1 September 2025, the seller was not allowed to sell it. Return it and, if you wish, report the seller to the national authority.
3. If it was bought before the ban, the regulation does not govern your private use. The earlier safety assessments found the amounts far below any level of concern. Using it up, or disposing of it as chemical waste, are both reasonable choices.
4. When buying new gel, look for TPO-free on the label and for an EU responsible person's address, which shows the product is notified and assessed under the regulation.
5. For home gel, also check that the list does not include HEMA or di-HEMA trimethylhexyl dicarbamate, which are restricted to professionals and are the usual cause of gel allergy.

Anyone who develops itching, swelling, blistering or nail lifting after a gel manicure should stop using gel and see a GP or dermatologist. Acrylate allergy, once acquired, is lifelong and can affect future dental and medical treatments that use the same chemistry.

What replaces TPO in gel polish?

Reformulated gels use other photoinitiators. TPO-L, ethyl phenyl(2,4,6-trimethylbenzoyl)phosphinate, is a close relative that is not classified CMR and absorbs in a similar range. BAPO-type initiators, such as phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, are also used. Each behaves a little differently under the lamp, which is why some reformulated gels cure more slowly, need a stronger lamp or shift slightly in tone.

TPO-free has become a standard claim on EU gel products. The Dutch brand LAKKIE, for example, markets its cat-eye gels as HEMA and TPO free⁸, and Essie states that its long-wear lacquers are formulated without TPO⁹. The second claim is true of every solvent polish, since none contains a photoinitiator.

Does the TPO ban affect regular nail polish?

No. Regular nail polish is nitrocellulose dissolved in solvents that evaporate, with plasticisers, resins and pigments. Nothing in it cures under light, so there is no photoinitiator to remove. The ban changed nothing in the formula of any solvent lacquer, and a bottle of ordinary polish bought before or after 1 September 2025 is the same product⁷.

The same is true of the HEMA rule. A lacquer with no methacrylate monomer, such as an India Anaïs crème, needs no lamp and falls outside both gel rules. For readers who want a long-wear manicure without a photoinitiator, an acrylate monomer or a lamp, solvent polish with a good base and top coat remains the option that no reformulation has touched.

“The amount of this ingredient used in nail products is over a thousand times less than the amount which could have any negative effect on fertility.”

Caroline Rainsford, Director of science, CTPA, quoted in Chemistry World

Written and fact-checked by the India Anaïs editorial team. Every number and rule is linked to its source. How the guides are made.