TPO added to European Union list of prohibited ingredients

On 12 May 2025, the EU Commission published legislation, known as the 7^th CMR Omnibus Regulation, to add 22 new substances to the list of ingredients prohibited for use in cosmetics.  

The list includes Trimethylbenzoyl diphenylphosphine oxide (TPO). TPO is used in some UV gels and hybrid nail polishes helping product to harden and cure under UV light. It was previously permitted for professional use only but now will be prohibited in all settings.  

The 7th CMR Omnibus Regulation will take effect on 1 September 2025. From that date, products containing affected ingredients must no longer be sold or made available on the market.  

EU list of restricted and prohibited ingredients

The European Commission maintains the list of substances that are restricted or prohibited in cosmetic products. This list is contained in Annex II- Annex VI of the EU Cosmetics Regulation. Ingredients are added to the list when scientific assessments show they pose a potential risk to consumer health.  

Manufacturers, distributors and suppliers are responsible for staying up to date with Annex II-VI and ensuring their products remain compliant.  

It is also recommended to closely monitor the list of other ingredients currently under review by the Scientific Committee on Consumer Safety (SCCS), as these may be added to the Cosmetic Products Regulation in Annex II-Annex VI in future depending on the outcome of their safety assessments.  

Background to the inclusion of TPO in Annex II   

The Classification, Labelling and Packaging (CLP) Regulations in the EU aim to ensure a high level of protection of human health and the environment by identifying the hazardous properties of substances and mixtures.

Under the EU CLP Regulation (Regulation (EC) No 1272/2008), substances deemed carcinogenic, mutagenic, or reprotoxic (CMR) are classified into three categories based on the strength of evidence for their hazardous effects:

• CMR1A: substances for which there is clear evidence that they are carcinogenic, mutagenic or toxic to reproduction.
• CMR1B: substances for which these effects are possible but for which there is a need for further research for confirmation of the effects.
• CMR2: substances suspected of having carcinogenic, mutagenic or reprotoxic effects. The risk assessment requires further studies.

Under the CLP, TPO is now classified as belonging to the CMR Category 1B, resulting in its inclusion in Annex II of the European Cosmetics Regulation, prohibiting its use in cosmetic products.   

See the timeline below for an outline of the steps involved in classifying TPO as a CMR and the relevant legislative steps leading to the prohibition on it use in cosmetic products.

Actions for distributors and salon owners  

• After 1 September, distributors should not supply any products containing TPO.  

• Salon owners should: 

• Check the ingredient list of any UV-cured nail polishes or gels for TPO (INCI: Trimethylbenzoyl Diphenylphosphine Oxide).  
• Stop using products containing TPO after 1 September and dispose of them.   
• Confirm with your supplier that future stock will not contain TPO.
• Use reputable suppliers who stay up to date with regulatory requirements and can alert you to upcoming changes to cosmetics ingredients.

• Consumers concerned about TPO should speak with their salon owners about the products they use. Nail polishes containing TPO were intended for professional salon use only, and after 1 September products containing TPO should no longer be used. 

Timeline

The timeline below outlines the steps involved in classifying TPO as a CMR and the relevant legislative steps leading to the prohibition on it use in cosmetic products, which will come into force on 1 September 2025.