Multiuse Polystyrene Plates for Phasing Out Single-Use Plastics: Chemical Performances and Environmental Impact Assessment Through a Life Cycle Approach

European governments are addressing plastic pollution by implementing the Directive EU 2019/904 that bans single-use items like cutlery, plates, straws, and beverage stirrers. One strategy proposed by several industries to continue their production is the conversion of single-use items into multiuse items. Herein, the focus is on the production of polystyrene reusable plates and the suitability of this product for microwave and dishwasher use is assessed: in proper conditions, the structure is preserved without cuts or visible deformations, and the chemical stability is guaranteed. To get a full picture of the benefits and impacts of this new product, a life cycle assessment methodology is applied to compare the performances of one reusable plate with 20 single-use plates. Results indicate that proper use is crucial: a reusable plate disposed after one use is more impactful than a single-use plate. In contrast, the reuse of plates for 20 times allows to reduce carbon footprint and acidification potential. Eutrophication and ozone layer depletion, on the other hand, increase due to the washing phase. The solutions that can mitigate these issues and enhance the sustainability of the reusable plates include the improvement of the detergent compositions and the use of electricity from renewable sources.