The , authored by the Sustainable Materials Innovation Hub at The University of ԰������, explores the consequences of terminology choices on end-of-life solutions for plastic waste. While recycling has long been touted as a solution for plastic sustainability - it comes in many forms, and can sometimes serve as a smokescreen for genuine discussions around sustainability.

The researchers, Seiztinger, Lahive, and Shaver, find directional terms - such as ‘upcycling’ and ‘downcycling’ - to be poorly defined as value propositions, and that their use can skew perceptions of the benefits, potentially posing barrier to circularity.

‘Downcycling’, for instance, implies the production of a less favourable or ‘less good’ material as the end product of the recycling process, while ‘upcycling’ has positive connotations. However, despite what these terms suggest, a ‘downcycled’ stream may produce a high value product, while an ‘upcycled’ path may have a greater negative environmental impact than alternative routes.

Using these terms assigns disproportionate value to certain end-of-life plastic solution strategies, and can be used by supporters or detractors of different recycling technologies to obscure genuine evaluation of their environmental impact.

The study, published in the journal , suggests that plastic waste solutions consistently fail to live up to their marketed messaging, and that clearer communication of the true value of the product from a recycling process is essential to drive investment in proper plastic waste management. Corresponding author, Professor of Polymer Science at The University of ԰������, said: “The confused terminology surrounding the fate of waste plastic often lacks a consideration of value and unintended consequences. As these terms are now being used to promote technologies outside of a sustainable system, we felt it important to argue for clarity and caution when presuming quality from this directional terminology.”

The researchers argue that no single solution offers a quick fix, and that it is wrong for the terminology to suggest otherwise. They call for greater clarity over how we value end-products. They suggest a ‘spiral system’ of reuse, in which plastic materials are treated as complex mixtures that, like crude oil, can be chemically deconstructed at the end of their life and transformed to become a huge range of longer-lasting products over their lifetime.

For example, a yoghurt pot could be reconstituted into car parts, and then after that into a park bench. Ultimately, after many years of service, it could be chemically deconstructed, and turned back into a yoghurt pot. As the polypropylene in such simple packaging is already used in cars, hard shell suitcases, garden furniture, appliances, and plumbing, a cross-sector approach to reuse of plastic waste could generate more value than an approach focused solely on single-use packaging.

By moving away from direction-loaded terminology, researchers suggest that plastic waste solutions can be judged on the measurable environmental and economic value of the end-products, rather than an assumed or subjective value based on language, that is not always supported by full life-cycle assessment or economic analysis.

Dr Claire Seitzinger added: “Building a circular plastics economy means looking at the whole system, not isolated solutions pitched against each other. Policy, industry, innovation and collaboration across sectors are essential for a sustainable future. The next time you eat a yoghurt, where do you want the pot to end up? Should it become another yoghurt pot? A park bench? A car? What is best? And what should you, the packaging producer, or the government do to make that to happen?”

Paper details:

Journal: Cambridge Prisms: Plastics 

Full title: Up, down and back again: Value judgements in polymer recycling

DOI: https://doi.org/10.1017/plc.2026.10041.pr1