The EU's new hazard classes for chemical substances reached their final transition deadline on Nov. 1, 2026 for substances already on the market and in the supply chain before May 1, 2025. The classes were introduced by Commission Delegated Regulation (EU) 2023/707 and cover endocrine disruption for human health and the environment, PBT, vPvB, PMT and vPvM.
Substances first placed on the EU market from May 1, 2025 have been subject to the new rules since that date. From Nov. 1, 2026, substances placed on the market earlier must also be classified and labelled in line with the new hazard classes.
The deadline also affects REACH registration dossiers. ECHA has made the new hazard classes available in IUCLID and has said it will be mandatory to indicate whether a substance is classified under any of them. Where a substance does not meet the criteria, the reasons for that conclusion should be recorded in the dossier.
ECHA's validation rules indicate that the default IUCLID entry of "hazard class not assessed" will not be accepted after the transition period. Registrants should check that their CLP classification, safety data sheets and REACH registration dossiers are aligned.
