Propylidynetrimethanol (CAS No.77-99-6, EC No.201-074-9, INCI: Trimethylolpropane) is an ingredient listed in Cosing, with the functions: Humectant, Solvent.
The substance is currently not regulated under European Cosmetics Regulation 1223/2009, nor is it listed in Annex VI to the European CLP Regulation 1272/2008.

Norway intends to propose classifying the substance as follows.
• Repr. 1B, H360D - May damage the unborn child.

If the process is completed, Trimethylolpropane could be listed as a reprotoxic substance (and therefore CMR), and its use could be compromised in cosmetic products in Europe, unless exempted from the ban after consultation with the SCCS.

Source
• ECHA Weekly - Classification, Labelling and Packaging - New intentions and proposal to harmonise classification and labelling, ECHA, 24 June 2026
• Registry of CLH intentions until outcome - Propylidynetrimethanol, ECHA, 23 june 2026