European Union bans key ingredient in gel nail polish | What to know

The European Union has banned a key ingredient found in many gel nail polishes, effective Monday, Sept. 1.

The ingredient, trimethylbenzoyl diphenylphosphine oxide (TPO), helps gel and hybrid polishes harden under UV light.

While it had previously been restricted to professional use only, regulators say it is now prohibited in all settings, according to the Health Products Regulatory Authority (HPRA).

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TPO remains allowed in the United States and the ban is expected to go in to effect in the U.K. in 2026.

European regulators cited animal studies suggesting a potential safety concern.

However, it is not clear that gel nail polish poses a threat to human health given current exposure levels.

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Still, European regulators often take a more aggressive approach to regulation, more often banning substances that pose even a theoretical risk to human health rather than waiting for human studies.

Beginning Sept. 1, distributors throughout the European Union may no longer supply products containing TPO, and salon owners are urged to take action.

HPRA advises salons to review ingredient lists, stop using products with TPO, dispose of them properly and confirm with suppliers that future stock is TPO-free. Salons are also encouraged to source products from reputable distributors who closely track regulatory changes.

For consumers, experts recommend asking salons about the products being used. Since polishes with TPO were originally intended for professional use only, they should no longer be available after Sept. 1.

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Gel polish is popular because it is long-lasting and less prone to chipping.

U.S. agencies including the Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC) advise consumers to always read product labels, apply polish in well-ventilated areas and follow directions for safe use.