Safe and Sustainable by Design, Scoping, and Simplified Assessment of Alternative Flame Retardants for Use in Polymer Insulation Foams followed by Intermediate Assessment Ayse Ay1, Jean Louis Beckmann2, Petra Frank3, Sabine Fuchs2, Valeria Berner4, Jan Geerds4, Paul Barthel4, Benedikt Bitzer4, Tobias Moss5, Roberto Chinchilla5, Herbert Scharnagl6, Leonhard Ritter6, Maximilian Bernard6, Sabrina Zambotti7, Susan Dekkers8, Thomas Hennequin8, Carl-Christoph Höhne4, and Wendel Wohlleben1 1BASF SE, Carl-Bosch-Str. 38, 67056 Ludwigshafen, Germany. 2Hamm-Lippstadt University of Applied Sciences, 59063 Hamm, Germany. 3University of Siegen, 57076 Siegen, Germany. 4Fraunhofer Institute for Chemical Technology ICT, 76327 Pfinztal, Germany. 5Chemische Fabrik Budenheim KG, 55257 Budenheim, Germany. 6Steinbacher Dämmstoffe, 6383 Erpfendorf, Austria. 7GreenChemicals, 20832 Desio, Italy. 8TNO, 3584 CB Utrecht, the Netherlands. Results BASF SE Carl-Bosch-Strasse 38, 67056 Ludwigshafen am Rhein, Germany
[email protected] https://www.basf.com Objectives •Revisit Simplified assessments questionnaire to improve scoring accuracy and better reflect the potential of flame retardant candidates. •Initiate Intermediate assessments for selected alternatives, focusing on mechanistic and exposurerelevant evaluations. So far: •EPR spectroscopy for radical formation. •FRAS assay to assess oxidative damage potential. •Upcoming in-chemico NAMs in Intermediate assessments: Leaching testing in (i) Artificial sweat, (ii) Phagolysosomal Simulant Fluid (PSF) for mimicking intracellular degradation, (iii) Lung Lining Simulant Fluid (LSF) for simulating respiratory exposure. This project received funding from the European Union’s Horizon Europe research and innovation programme under grant agreement n°101177608. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union. Neither the European Union nor the granting authority can be held responsible for them. Introduction & Motivation The European Green Deal emphasizes the need for a Safe and Sustainable by Design (SSbD) strategy in chemical and material innovation. While guidance from JRC, CEFIC, and WBCSD exists, real-world R&D adoption is still lagging. PLANETS steps in to close this gap—applying a tiered SSbD framework to flame retardants, from molecular design to end-of-life. Initial Simplified assessments showed high uncertainty, prompting a shift to Intermediate with deeper, mechanistic evaluations with NAMs to better differentiate the safety and sustainability profiles of novel flame retardant alternatives. Revisit Simplified Assessment Questionnaire: Iteration is central to SSbD. Simplified assessments are revisited as new data and regulatory insights emerge. These findings reinforce the need for iterative evaluation, regulatory alignment, and data transparency in earlystage SSbD screening. In-chemico NAMs Testing Approach: 1. Representative Selection: One compound per molecular class was selected (e.g., Highest halogen content, highest phosphorus-sulfur (P–S) total content). 2. Dose Scanning: Each representative was tested across multiple concentrations using assays. The dose showing clear differentiation in response was identified. 3. Class-Wide Testing: The selected dose was then applied to all compounds within the same molecular class to ensure comparability. CONCLUSION & FUTURE WORK •While Simplified Assessment screening offered broad coverage, scoring uncertainties led to deeper evaluations. In intermediate assessment, in-chemico NAMs testing enabled the (i) assessment of oxidative damage potential (FRAS assay) and (ii) Evaluation of radical generation potential (EPR spectroscopy). •A flexible testing strategy ensured meaningful results even when certain assays were incompatible, supporting the prioritization of safer, high-performing alternatives and informing SSbD substitution guidance. Future work to support the selection of final candidates in intermediate assessment, followed by other dimensions: 1. Perform prospective LCA. 2. Expand intermediate assessment with leaching studies in (i) Artificial sweat, (ii) PSF, and (iii) LSF. 3. Explore in-silico predictive tools for hazard and sustainability. •Develop guidance documents and training modules to support SSbD adoption. Figure 1: Updated Simplified Assessment Questionnaire Heatmap. Figure 2: Heatmap of Intermediate in-chemico NAMs for PS–P–S Copolymers. (4) Due to exceeding CLP regulatory thresholds. (2) Due to presence of flame retardant coatings that are associated with substances under upcoming regulatory scrutiny. Topic PS-P-S copolymer TEMPO DOPO DICUMENE Brominated SBS s-triazine phosphonates Phosphoryl carbamates Phosphonate APP APP + Siloxane APP + Melamine APP + Silane APP + MF Release of hazardous susbtances -10 10 10 10 10 ? ? -10 -10 -10 -10 -10 -10 CLP limit exceeded 10 -10 -10 -10 -10 ? ? 10 10 10 10 10 10 Upcoming regulation relevant substances 10 10 10 10 -10 ? ? 10 10 ?-10 10 -10 HAZARD Improvement Degradation Degradation Degradation Degradation Equal Equal Degradation Improvement Equal Degradation Improvement Degradation Applicability 10 10 10 10 10 10 10 10 10 10 10 10 10 Dust or aerosol generation -10 -10 -10 -10 -10 10 -10 10 -10 -10 -10 -10 -10 Persistent fibers 10 10 10 10 10 010 10 10 10 10 10 10 Multi-component 10 10 10 10 10 10 10 10 10 -10 -10 -10 -10 Vapour release 10 10 10 10 10 -10 10 10 -10 -10 -10 -10 -10 Substantial materail breakdown -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 Skin (in)direct contact -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 -10 Workplace exposure measures 10 10 10 10 10 10 10 10 10 10 10 10 10 Oral consumer exposure 10 10 10 10 10 10 10 10 10 10 10 10 10 EXPOSURE and RELEASE Equal Equal Equal Equal Equal Improvement Improvement Improvement Degradation Degradation Degradation Degradation Degradation Non-sustainable or critical raw material 10 10 10 10 10 ? ? 10 10 10 10 10 10 Climate change & energy ? ? ? 0 0 ???????? Circular economy ? ? ? 0 0 ???????? Resource efficiency ? ? ? 0 0 ???????? Pollution reduction ? ? ? 0 0 ???????? Water protection ? ? ? 0 0 ???????? Biodiversity ? ? ? 0 0 ???????? Health safety ?-10 -10 0 0 ? ? 10 10 ?0?0 ENVIRONMENT #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! #REF! Marketability ?10 10 10 10 10 10 10 10 10 -10 10 -10 Production tonnage -10 10 10 10 10 10 10 10 10 10 10 10 10 Financial market potential ?-10 -10 ?-10 10 10 10 10 10 10 10 10 Expected purchase price 10 10 10 10 10 -10 -10 -10 -10 -10 -10 -10 -10 Capital expenditures and operational costs 10 10 10 10 10 10 10 ?????? Probability of sucess 010 10 10 10 10 010 10 10 10 10 10 ECONOMY Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Human basic rights and needs 010 10 10 10 10 10 10 10 10 10 10 10 New jobs, knowledge and skills 10 10 10 10 10 10 10 10 10 10 10 10 10 Fair competetition and IP rights 10 10 10 10 10 10 10 10 10 10 10 10 10 Zero hunger ?0 0 0 0 ???????? SOCIAL Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement Improvement SSbD Score # Strong negative (C --) to neutral (B) 27 Strong negative (C --) 4 Negative (C -) to Neutral (B) 1 Negative (C -) 2 Neutral (B) 9 Neutral (B) to Strong Positive (A++) 2 References. [1] Andruschko, M., et al., A set of intrinsically flame retardant, halogen-free styrenic copolymers: Synthesis, characterization, processing, and properties, Polymer Degradation and Stability, 2025. [2] Frank, P., et al. (2024). Fire-retardant copolymers and molding compounds (U.S. Patent Application No. US20240084120A1). U.S. Patent and Trademark Office. [1] [1] [2]
