Tejal Somvanshi
Rahul Somvanshi
UK regulators have banned trimethylbenzoyl diphenylphosphine oxide (TPO), a key chemical used in gel nail polishes, from August 15, 2026, following the European Union’s decision to ban the substance a year earlier. The Resident first reported the UK ban taking effect immediately for new product sales. The photoinitiator—the compound responsible for curing gel polish under UV and LED lamps—has been classified as a reproductive toxicant based on animal testing, prompting authorities across Europe to act.
The European Union introduced its ban in September 2025 after classifying TPO as a CMR category 1B substance, a designation indicating presumed harm to human fertility derived from animal studies (CTPA). The UK has adopted comparable reasoning for its domestic prohibition, which takes effect immediately for new product sales but allows a transition period for existing inventory.
Salons across the UK can continue using TPO-containing products already in stock until February 14, 2027, providing six months for businesses to exhaust supplies and transition to alternative formulations. However, retailers and salons cannot purchase additional TPO-containing products from this point forward. The transition period aims to balance regulatory caution with practical business considerations.
The scientific basis for the ban centers on animal studies demonstrating reproductive concerns, though experts acknowledge the actual human risk differs substantially from laboratory findings. Caroline Rainsford, director of science at the Cosmetic, Toiletry and Perfumery Association, noted that while animal testing indicated potential harm, “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” (CTPA). The CTPA noted this significant gap between laboratory observations and real-world exposure has not deterred regulatory action, reflecting a precautionary approach to substances classified in the highest reproductive hazard categories.
Consumers currently using gel nail products should check ingredient lists for TPO’s chemical name—trimethylbenzoyl diphenylphosphine oxide—to identify which products contain the banned substance. Those with concerns about recently purchased items can contact Trading Standards through the Citizens’ Advice Consumer Helpline for suspected illegal products still in circulation after February 14, 2027.
The cosmetics industry has already responded to regulatory pressure. Multiple manufacturers including Manucurist, OPI, Après Nail, Aimeili, and Bio Seaweed Gel have introduced TPO-free gel formulations, indicating that alternatives are commercially viable and increasingly accessible to salons. These alternatives use different photoinitiator compounds to achieve comparable curing times and durability.
The UK ban does not align uniformly with international regulation. American authorities have not banned TPO federally, though the FDA oversees it in cosmetics. This reflects different regulatory philosophies, with European authorities applying stricter precautionary principles to reproductive hazard classifications.
The transition period ending in mid-February 2027 gives UK salons a clear timeline to complete stock rotation. The ban shows how reproductive toxicant classification can trigger rapid regulatory action, even when actual exposure calculations suggest minimal practical risk to users.
