Cyclosiloxanes, including D4, D5, and D6, are a class of organosilicon compounds with unique chemical structures. Widely used across multiple industries, they have also drawn significant attention due to their potential environmental and health risks. This article provides a comprehensive overview of the EU’s recent regulatory developments targeting these substances.

Since January 1, 2025, the grace period related to the Poison Center Notifications (PCN) to the European Union (EU) Poison Centers has come to an end. This means that companies must submit and successfully notify the unified format of notification dossiers before they can place their products on the EU market. After the deadline for industrial mixtures passed on January 1, 2024, the Hungarian appointed body has been conducting reviews of the submitted PCN dossiers. The main focus of the review is to check whether the information in the dossiers complies with the requirements of the CLP Regulation. The content of the PCN notification is mostly derived from the Safety Data Sheet (SDS) of the product, especially the toxicological information, which is the entire content of Section 11 of the SDS. Therefore, to pass the review by the Hungarian appointed body, companies must prepare an SDS that is fully based on the CLP standard when submitting the PCN notification.

Exporting chemicals to EU countries requires the provision of labels and Safety Data Sheets (SDS). Manufacturers, importers, and downstream users in the EU often worry that disclosing all components of a mixture on the label or SDS might lead to the leakage of trade secrets. Therefore, it may be necessary to use alternative chemical names to protect confidentiality and intellectual property rights.

On November 20, 2024, the European Union published Commission Regulation 2024/2865 (REGULATION (EU) 2024/2865 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL) in its Official Journal, amending the EU CLP Regulation (Regulation (EC) No 1272/2008 on classification, labeling, and packaging of substances and mixtures). The amendment regulation takes effect on December 10, 2024, with most provisions becoming mandatory from July 1, 2026 (18 months), and the remaining provisions applicable from January 1, 2027 (24 months).

The European Chemicals Agency (ECHA) has released the Guidance on the Application of the CLP Criteria on its official website on November 13, 2024. Unlike the single document versions released from 2009 to 2024, the new guidance is split into five separate document, covering overview, general principles for classification and labeling, physical hazards, health hazards, environmental hazards and other hazards.

The European Poison Centre (PCN) reminded businesses that the transition period (January-December 2024) is concluding.

On June 24, 2024, the UK's CLP authority, HSE, announced that it has granted legal effect to 88 chemical substances listed in the UK's Mandatory Classification and Labelling (GB MCL) list. This update took effect immediately upon its release and complies with regulations. The updates are based on the 14th and 15th Adaptations to Technical Progress (ATP), which update the CLP Regulation, issued by the European Commission.

Starting from 2023, the amendments to Annex II of REACH regulation on safety data sheets (SDSs) became mandatory. This means that related enterprises must affix a unique formula identifier (UFI) code in section 1.1 of their SDS when exporting mixtures to the EU. Mixtures that meet specific conditions must also complete poison center notification (PCN).

The European Commission has recently published regulation (EU) 2023/464, which amends the Annex to Regulation (EC) No 440/2008, a set of test methods under the Registration, Authorization and Restriction of Chemicals (REACH) regulation. In this amendment, a number of new OECD in vitro test methods are introduced while some old test methods are removed such as Two-Generation Reproduction Toxicity Study (OECD 416) and Unscheduled DNA Synthesis (UDS) Test with Mammalian Liver Cells in vivo (OECD 486), which promotes the application of in vitro test methods in the EU.

On March 31, 2023, the European Commission released the amendments to Annex I to Regulation (EC) No 1272/2008 as regards hazard classes and criteria for the classification, labelling and packaging of substances and mixtures (CLP), introducing several new classification criteria to identify endocrine disrupting chemicals (EDCs) and persistent and mobile substances.