Industry Webinar Explores the Proposed Expansion of the EU Harmonised Classification of Styrene

The webinar followed confirmation that the Dutch National Institute for Public Health and the Environment (RIVM) is preparing a proposal to amend the existing EU harmonised classification of styrene. In addition to the current harmonised classification, RIVM has indicated that it intends to submit a proposal to classify styrene as Carcinogen Category 1B and Germ Cell Mutagen Category 2, together with Specific Target Organ Toxicity, Repeated Exposure Category 1 (lungs).

Hosted by Crowell & Moring LLP, the webinar brought together experts in toxicology, regulatory affairs, law and industry to review the scientific evidence underpinning the proposed classifications, explain the EU harmonised classification and labelling process and discuss the potential regulatory, economic and societal implications for manufacturers and downstream users of styrene and styrene-based products.

The discussion also placed styrene in the wider context of Europe’s industrial resilience and strategic autonomy. Styrene was among the strategic building-block molecules identified by eight EU Member States in their 2025 call for a Critical Chemicals Act. Its downstream value chains underpin a broad range of strategically important applications, including renewable energy, energy efficiency, food packaging, cold-chain logistics, transportation, and marine infrastructure.

Speakers represented organisations from across the styrenics and composites sectors, including Plastics Europe, the Cefic UP/VE Sector Group, CompositesNL, the European Boating Industry (EBI), the American Composites Manufacturers Association (ACMA), and independent scientific and legal experts. The programme also considered lessons from previous harmonised classification cases, including titanium dioxide, together with perspectives from both Europe and the United States.

A balanced discussion

Throughout the 90-minute webinar, speakers stressed that any future regulatory decision should be founded on robust scientific evidence and a transparent evaluation of all available data. The programme brought together scientific, legal and industry perspectives on both the proposed classifications and the wider regulatory process.

Presentations reviewed the scientific evidence relevant to the anticipated proposal, including toxicological and epidemiological studies, differing interpretations between scientific bodies, and the relevance of mode-of-action data. Speakers outlined why, in their view, the available scientific evidence does not support the classifications proposed by RIVM. They also explained the legal framework governing the CLH process, the role of ECHA's Committee for Risk Assessment (RAC), and the opportunities available for stakeholder engagement once the dossier is submitted. The practical implications of any future classification were also explored, including potential impacts on occupational risk management, downstream legislation, customer requirements, product stewardship, and future investment decisions.

The legal presentation emphasised that the CLP framework requires a weight-of-evidence approach that considers all relevant available information collectively, including positive and negative findings, human and animal data, and evidence concerning the mechanism or mode of action. Speakers expressed concern as to whether the preliminary reasoning communicated to date reflects the full body of evidence available for styrene. As the dossier has not yet been published, these concerns will ultimately need to be assessed against the final submission and examined through ECHA’s conformity check, public consultation and RAC evaluation.

The essential role of UP/VE resins

A dedicated session highlighted the essential role of styrene-based unsaturated polyester and vinyl ester resins in enabling durable composite materials used in drinking water infrastructure, renewable energy, transportation, marine applications, construction and corrosion-resistant industrial equipment. Speakers noted that these applications support Europe’s objectives for resilient infrastructure, decarbonisation and industrial competitiveness through long service life, lightweighting and reduced maintenance requirements.

Looking beyond hazard classification

A recurring theme throughout the webinar was that hazard classification is only one element of chemical risk management. Several speakers emphasised the important distinction between hazard, the intrinsic properties of a substance, and risk, which depends on exposure and the effectiveness of risk management measures during manufacture and use. Speakers also noted that, while harmonised classification is a hazard-based scientific process, broader socio-economic considerations become highly relevant when assessing the downstream regulatory and risk-management measures that may follow. The discussion therefore emphasised the importance of taking into account the wider societal, environmental, and economic consequences of regulatory decisions, particularly where substances play a critical role in industrial applications and where technically feasible alternatives remain limited for many of the styrene applications discussed.

The webinar concluded with an overview of opportunities for stakeholder engagement once the proposal is submitted.

Regulatory update and next steps

Following the webinar, RIVM confirmed that submission of the CLH dossier had been postponed from the previously anticipated spring 2026 timetable to August–September 2026. Although the reasons for the revised timetable have not been publicly detailed, the delay has provided stakeholders with additional time to prepare relevant scientific and technical evidence.

Once submitted and accepted following ECHA’s conformity check, the dossier will be opened for public consultation. Stakeholder comments and supporting evidence submitted during the consultation will be considered by RAC as part of its scientific assessment and the development of its opinion. The webinar demonstrated the value of early engagement and preparation ahead of this formal process.

A recording of the webinar is available at:

https://vimeo.com/1188179882/31df864f70?fl=tl&fe=ec

To receive future updates on regulatory developments relating to styrene, please contact:

information@styrenealliance.com