What’s new?
On 25 June 2025, the European Chemicals Agency (ECHA) published the 33rd update to the REACH Candidate List of Substances of Very High Concern (SVHC), adding three new substances and bringing the total number of entries to 250.
Two of the newly added substances are siloxanes commonly used in cosmetic formulations: 1,1,1,3,5,5,5-heptamethyl-3-[(trimethylsilyl)oxy]trisiloxane (also known as Methyltrimethicone) (CAS 17928-28-8) and Decamethyltetrasiloxane (CAS 141-62-8).
Both substances were proposed by Norway for inclusion based on their very persistent and very bioaccumulative (vPvB) properties under REACH Article 57(d). These linear siloxanes are characterised by their excellent lubricity, low surface tension, good spreadability, and stability, making them valuable ingredients in cosmetic formulations. However, their unique structure results in high environmental persistence and bioaccumulation, making them resistant to degradation and prone to accumulating in organisms.
What now?
Both ingredients are expected to be either banned or strictly restricted to impurity levels in the future.
References
European Chemicals Agency. ECHA adds three hazardous chemicals to the Candidate List. 25 June 2025.