Assessing degradation and biofilm formation on disposable food containers of various materials in a lake environment

Microplastic particles are persistent micropollutants that pose a danger to ecosystems and their biodiversity, both through their direct toxic action and by creating a distinct ecological niche that can host a different assortment of microorganisms. In this regard, the presented study explores the changes that occurs during the exposition to the surface waters of Lake Maggiore (Italy) of different commercially available food containers, including conventional materials like polypropylene (PP) and polyethylene terephthalate (PET), as well as innovative biodegradable materials like Mater-Bi, and natural materials such as wood and cellulose. Already after 43 days of environmental exposure, spectral changes, as revealed by FT-IR spectroscopy in PET and Mater-Bi, along with alterations in thermal properties of all human-made materials, indicated the occurrence of a degradation process. Despite similar bacterial richness, the biofilms on PET, PP, and Mater-Bi differed significantly from those on both natural materials and the planktonic community. The communities on human-made materials showed a higher proportion of potential pathogens, with PET and PP exhibiting increased abundances of antibiotic resistance genes. Overall, these findings stress the need for dedicated strategies to curb the spread of human-made polymers in freshwaters, including innovative materials that, due to their biodegradable properties, might be perceived as less hazardous for the environment. Also see: https://micro2024.sciencesconf.org/558919/document