EU bans common gel-nail ingredient TPO over reproductive and cancer concerns

The European Union on Sept. 1, 2025, imposed a ban on trimethylbenzoyl diphenylphosphine oxide, commonly known as TPO, a chemical used in many gel nail polishes after regulators reclassified it as a Category 1B carcinogenic, mutagenic or toxic-to-reproduction (CMR) substance. Under EU chemical safety rules, that reclassification automatically barres the substance from cosmetic products sold in the bloc.

TPO is a photoinitiator that helps gel polishes cure quickly and produces the glossy, hard finish that has made gel manicures popular. The decision to ban the ingredient follows a body of studies, many conducted on animals, that linked TPO exposure to adverse effects on fertility and reproductive health. EU authorities said the evidence was sufficient to justify a precautionary approach under the bloc’s regulatory framework.

Manufacturers, salons and consumers face immediate changes. Products on the market in the European Union that contain TPO must be withdrawn or reformulated, and sellers can no longer place new TPO-containing gel polishes on the EU market. Regulators and industry groups said not all gel formulas include TPO; alternative photoinitiators exist, but reformulation and regulatory compliance will take time and could affect supply and prices.

Gel manicures are widely used because they are cured under ultraviolet or LED lamps and can remain chip-free for weeks. Social-media usage reflects the trend’s popularity: BBC Bitesize has noted millions of posts under #gelnails on Instagram and TikTok. The EU’s move does not amount to a blanket ban on gel manicures themselves, only on products containing the newly classified compound.

The EU’s decision highlights differences in chemical regulation between jurisdictions. The United States has not implemented a similar ban on TPO, and the compound remains in use in some U.S. formulations. EU regulators typically apply a precautionary standard for cosmetics that has led to earlier bans or restrictions on other substances that remain permitted elsewhere.

Industry reactions have varied. Some salons reported immediate uncertainty about inventory and client bookings, while manufacturers said they would accelerate efforts to reformulate products without TPO. Retailers selling directly to consumers in the EU will be required to remove affected formulations from shelves. National authorities within the bloc are responsible for enforcing the ban and overseeing compliance.

Scientific studies cited by regulators primarily involve animal models and laboratory tests; regulators concluded the available evidence warranted classification as a substance that may impair fertility or cause harm to reproduction. The EU’s classification process assesses hazard potential and, in this case, triggered an automatic regulatory response under the bloc’s chemicals legislation.

The ban raises questions for countries outside the EU, including the United Kingdom, where regulatory decisions on cosmetics are made independently. UK authorities have not adopted an identical prohibition as of the EU effective date; any decision there would follow the U.K. regulatory process and available evidence.

Salon operators and consumers seeking to avoid TPO can look for product ingredient lists or consult manufacturers. Some gel polishes already use alternative photoinitiators, and the industry anticipates a shift toward TPO-free formulations in the EU market. Regulators and public-health advocates have emphasized that the move is intended to reduce potential long-term risks associated with repeated exposure.

The EU ban marks a notable example of how regulatory frameworks can rapidly remove a widely used ingredient when it is reclassified under hazard-based criteria. Manufacturers and sellers that serve the European market now face immediate compliance obligations, while researchers, regulators and industry groups continue to evaluate safer alternatives and monitor implications for consumers and businesses.