TPO, the photoinitiator used in most UV- and LED-cured gel nail systems, cannot be placed on the Great Britain market in newly supplied cosmetic products from August 15, 2026, under Statutory Instrument 2026/23.

The same instrument already banned the UV filter 4-MBC (3-(4′-methylbenzylidene)-camphor, INCI: Enzacamene) from newly placed cosmetics on July 15, 2026, and lowered the trigger for the "releases formaldehyde" warning on Annex V preservatives from 0.05% to 0.001% of formaldehyde released by the finished product.

For brands, manufacturers and Responsible Persons, this is a labelling and formulation reset. For nail technicians, training academies and the broader salon channel, it is a stock audit that cannot wait until late summer.

What changed on July 15, 2026?

SI 2026/23, in force in England, Scotland and Wales, delivered two amendments on July 15.

4-MBC is now prohibited. The Government's explanatory memorandum cites "a potential risk to human health" as the basis for the ban. Products lawfully placed on the GB market before July 15, 2026 may continue to be supplied until the end of January 14, 2027.

The formaldehyde warning threshold dropped by a factor of 50. Finished products containing Annex V preservatives must now carry the wording "releases formaldehyde" when the released formaldehyde exceeds 0.001%, down from 0.05%. SI 2026/23 also swaps "contain" for "release" in the wording, reflecting the actual exposure pathway.

The Cosmetic, Toiletry and Perfumery Association (CTPA) treats January 15, 2027 as the corresponding off-shelf date for July-affected stock.

What changes on August 15, 2026?

A second tranche lands mid-August, also under SI 2026/23 and the companion SI 2026/109.

Sixteen CMR substances move to Annex II. The CTPA says Trimethylbenzoyl Diphenylphosphine Oxide (TPO) is the only one of the 16 with an INCI name known to appear in cosmetic products, putting the photoinitiator squarely at the centre of the regulatory change.

TPO cannot be placed on the GB market in newly manufactured or imported cosmetic products from August 15, 2026. Stock lawfully placed on the market before that date may continue to be supplied until the end of February 14, 2027, with February 15, 2027 as the corresponding off-shelf date.

SI 2026/109 caps Hexyl Salicylate product by product. The fragrance material, INCI Hexyl Salicylate (Hexyl 2-hydroxybenzoate), moves to Annex III rather than a ban. Limits drawn from Schedule 2 of the instrument include:

• Adult and child fragrances (over three): 2%
• Rinse-off skin and hair products: 0.5%
• Nail products: 0.5%
• Leave-on skincare, face makeup, lip products, deodorants, leave-on hair products: 0.3%
• Toothpaste and mouthwash: 0.001%
• Products for children under three: generally 0.1%, varying by category

Products containing Hexyl Salicylate above their category ceiling, lawfully placed on the GB market before August 15, 2026, may continue to be supplied until the end of February 14, 2027.

What should formulators and procurement teams do?

Nail-system buyers should identify every UV- and LED-cured product in the cabinet: gel polish, builder gel, base coat, top coat, sculpting gel and bonding products. Read the INCI list for Trimethylbenzoyl Diphenylphosphine Oxide. Not every gel in every brand contains it, so written supplier confirmation matters more than blanket assumptions.

For Hexyl Salicylate, label presence is not the same as non-compliance. The supplier or Responsible Person holds the concentration data, not the salon.

In both cases, the document trail is the safeguard: invoices, batch numbers, order confirmations and written supplier responses will underpin any Trading Standards query after the off-shelf dates pass.

On continued professional use, the CTPA has aligned with Trading Standards on an interpretation that lets salons keep using legally acquired professional stock past the supply deadline, although no further purchase is possible once the off-shelf date arrives. That is industry guidance, not statutory text.

How should salons talk to clients about TPO?

The British Association of Beauty Therapy & Cosmetology (BABTAC) has urged the trade to handle the change calmly. Chief executive Lesley Blair MBE said:

"It is always important that any concerns around product ingredients are taken seriously, particularly in an ever-evolving nail industry. However, it's equally important to put the TPO ban into context."

She added: "This is why we continue to encourage consumers to visit appropriately trained professionals who understand safe product application, curing and hygiene standards."

Counter scripts should make three points: the ban follows TPO's classification under separate chemicals legislation rather than a new safety incident, legally sold products have passed a cosmetic safety assessment, and reformulated ranges are coming through.

Does the August 15 regime extend to Northern Ireland?

No. SI 2026/23 and SI 2026/109 are GB instruments. Northern Ireland continues to follow the EU Cosmetics Regulation under the Windsor Framework, with its own deadlines and concentration tables. Operators running both jurisdictions need to check each SKU against the rules of its destination market.

The next data points to watch are whether reformulated gel systems reach UK distributors ahead of the August 15 placement deadline, and whether the GB and EU Hexyl Salicylate schedules converge on a single set of category ceilings or continue to diverge.