From waste to resource: The untapped value of the separate collection of single-use laboratory plastics to enable recycling

Publisher abstract

In the face of the sustainability crisis, scientific laboratories, as resource-intensive units, must conduct research more sustainably. They are estimated to produce 5.5 million tonnes of plastic waste per year. Clearly, there is a need for greater circularity: Reduce-and-reuse frameworks for laboratory plastics exist to some extent, but none for recycling of disposed single-use articles. Biologically contaminated plastics from life science labs are disinfected by autoclaving after use, transforming them into conventional residual waste that is mostly incinerated, resulting in high CO2 eq. emissions. However, this waste stream consists of high-quality polymers, for which (thermo-)mechanical recycling is technically possible. Therefore, we performed a waste assessment of lab plastics and found in a one-week assessment that the majority of the residual waste consisted of recyclable plastics. However, autoclaving causes these mixed fractions to clump together. Thus, we created a separate collection scheme for the two most abundant plastic types, polystyrene and polypropylene, enabling us to retrieve high-quality monostream polymer fractions for (thermo-)mechanical recycling. This study is the first to present a transferable blueprint with detailed instructions for other institutions on how to implement the separate collection scheme. We obtained user feedback on the feasibility and demonstrated 85% user acceptance. Further, this study provides the first quantitative assessment of emission-saving potential associated with substituting incineration with (thermo-)mechanical recycling for laboratory single-use plastics. For two end-of-life scenarios – an institution-specific scenario at the University of Konstanz (waste incinerated in Weinfelden, Switzerland) and a national average (Germany) scenario – we calculated the average annual emission-saving potentials for the extrapolated amount of arising waste to be up to 10.6 t CO2 eq. and 7.2 t CO2 eq., respectively. Therefore, a separate collection of lab plastic waste offers an easy-to-implement measure to reduce incinerated plastic waste, thereby lowering emissions and increasing the sustainability of laboratory research.