Existing material selection methods seem to offer limited support for addressing substance safety in practice, as the focus remains on intrinsic material properties and less on exposure risk. This hinders Safe and Sustainable by Design (SSbD) efforts that can prevent use and accumulation of substances of concern (SoCs) across product lifecycles in a circular economy. This study reviews 29 sustainable material selection methods to evaluate how they do support substance safety. Results show that substance safety is generally embedded within the broader sustainability realm without explicit risk or lifecycle-based assessment. Of the four steps that can be distinguished in material selection, most methods support the steps ‘Establishing a set of candidates’ and ‘Comparing candidates’ but the steps ‘Formulating selection criteria’ and ‘Choosing suitable candidates’ are often unsupported, leaving critical substance safety trade-offs unaddressed. The importance of mindsets such as systemic thinking and iterative reflection is recognized but underrepresented. The findings highlight the need to adapt existing methods with better guidance and risk integration to advance SSbD in material selection.

Consumers often replace electronic products prematurely due to performance issues (Van den Berge et al., 2021). Repair is a promising strategy to extend product lifetime by correcting faults to restore functionality (Pamminger et al., 2017) or realigning the product performance with users’ functional expectations via upgrades (Godfrey et al., 2022). However, repair activities declined over the past decades with 60% consumers disregarding repair when products malfunction (Magnier & Mugge, 2022). Recent consumer studies have revealed the barriers to repair. Consumers often struggle to diagnose product failures (Ackermann et al., 2018; Pozo Arcos et al., 2021), causing uncertainty about repair paths. Previous negative repair experiences further demotivate repair (Sonego et al., 2022), making consumers doubt its value (Svensson-Hoglund et al., 2022). The uncertainty about the availability of spare parts, clear repair instructions, and trustworthy repair services increase concerns about repair (Jaeger-Erben et al., 2021; Sonego et al., 2022). These lead to a lack of consumers’ trust, acceptance and adoption of repair practices. […]

Product service systems (PSSs) are revenue models where customers pay the company for the service the product provides, not (only) for the physical product itself.
Designing the revenue model along with the product can align economic incentives with environmental impacts, so the company has an incentive to design products for longer lives.
Both the company and the customer can benefit financially from longer‑lived products billed as services.
Not all product service systems are sustainable environmentally or socially, but if properly designed, they can greatly enable the circular economy.

The Cradle to Cradle (C2C) concept takes natural systems as a source of inspiration, striving toward a positive vision where human society and industry regard waste as “food” for new cycles of use, and are powered entirely by renewable energy. Cradle to Cradle is not about efficiency but about effectiveness—waste need not be minimized if it is food for other cycles, providing positive regenerative impacts. However, this is difficult to achieve in practice. The Circular Economy concept elaborates on the Cradle to Cradle model, prioritizing longer product lifetime and recovering whole products over material recovery through recycling.
The Circular Economy also combines ecological thinking with economic thinking, making a business argument for sustainability.
Both concepts have been very influential in shaping the way we think about design for sustainability.

The validity and reliability of four prevalent reparability scoring systems has been investigated by comparing scores of ten smart phones and six vacuum cleaners versus empirically measured repair times, as well as comparing hypothetical ideal and problematic scenarios. Ease of disassembly methods was also assessed for five smart TVs, four washing machines and six vacuum cleaners. The scoring systems studied were the French Reparability Index (FRI), Joint Research Centre Scoring System (RSS/JRC), iFixit, and ONR19202. Overall scores of products across scoring systems were relatively well correlated, indicating a fair amount of overall reliability. However, the variability in scores for the best and worst case of the same product was often larger than the differences between products. Validity was good for products that are easily repairable, but scorecards often failed to score low when repair is infeasible or too expensive. Repair scores greatly depend on disassembly; since some scorecards count numbers of disassembly steps and other scorecards use proxy times, these two methods were compared against empirical disassembly times for five vacuum cleaners, five televisions, and four washing machines. The proxy time method was found to be highly accurate for all three product categories; the steps method was less so. It indicated the relative ease of disassembly well for washing machines, but not for televisions or vacuum cleaners. Finally, this study proposes improvements to scoring methods, including a limiting factor approach and the development of clearer protocols, to ensure the scoring systems are robust, reliable, and can effectively guide sustainable product design.

Devulcanization has the potential to help meet circular economy goals by recovering end-of-life rubber. However, the adoption of devulcanized rubber by manufacturers remains low at the industry level. Devulcanization value chains are complex and involve multiple stakeholders, including waste collectors, sorters, recyclers, compounders, manufacturers and regulatory bodies. This study investigated the barriers compounders and manufacturers face when incorporating devulcanized rubber into new compounds and identified primary underlying causes. The research was conducted through in-depth interviews with compounders and manufacturers of tires and general rubber goods, focusing on the technical, market, institutional, and cultural factors related to incorporating recycled materials, specifically devulcanized rubber. From the results, we identified a number of barriers faced by the industry. A key barrier was the heterogeneity of devulcanized rubber, which made it more difficult to add to new rubber compounds with consistent quality. Other barriers included a lack of standardization and coordination, along with misaligned regulations that hamper the market adoption of devulcanized rubber. This implies that increasing the uptake of devulcanized rubber at the industry level will not be achieved through technological advancements alone or isolated market interventions; instead, it requires comprehensive, systemic solutions.

Wind turbine blades, though key to green energy, pose recycling challenges due to their material composition. This study explored reshaping thermoplastic composite blades—an emerging, more recyclable design—into useful applications without altering the material composition. First, key characteristics like material structure and thickness were defined after which sample material was produced. Reshaping experiments were conducted for both single and double curved geometries with different reshaping methods and parameters. The promising results were translated into a demonstrator re-use application, a lamppost, showcasing reshaping as an alternative to shredding in circular blade strategies.