On 17 September 2025 2024, ECHA (European Chemicals Agency) made public Norway’s proposal for harmonised classification and labelling (CLH) for Trimethyl Pentanyl Diisobutyrate, a plasticiser, as a reprotoxic substance and endocrine disruptor.
1-isopropyl-2,2-dimethyltrimethylene diisobutyrate (CAS No.6846-50-0, EC No.229-934-9, INCI: Trimethyl Pentanyl Diisobutyrate) is an ingredient listed in the Cosing, with the function: Plastisiser.
The substance is not currently regulated by European Cosmetics Regulation 1223/2009, nor is it listed in Annex VI of European CLP Regulation 1272/2008.
Norway proposes the following classification.
• Repr. 2, H361d - Suspected of damaging the unborn child.
• ED HH 1, EUH380 - May cause endocrine disruption in humans.
If the process is completed and this classification becomes effective, this substance could be listed as a CMR and an endocrine disruptor, and its use could be banned in cosmetic products in Europe, unless the ban is waived following an opinion from the SCCS.
Sources
• ECHA Weekly - New intentions and proposal to harmonise classification and labelling, ECHA, 17 September 2025
• Registry of CLH intentions until outcome - 1-isopropyl-2,2-dimethyltrimethylene diisobutyrate, ECHA, 17 September 2025
