Nanoplastic exposure affects the intestinal microbiota of adult Drosophila flies

Micro- and nanoplastics (MNPLs) are emerging environmental pollutants that have garnered significant attention over the past few decades due to their detrimental effects on human health through various exposure pathways. This study investigates the impact of MNPLs on gut microbiota, utilizing Drosophila melanogaster as a model organism. Drosophila was selected for its microbiota's similarities to humans and its established role as an accessible and well-characterized model system. To analyze microbiota, full-length 16S rRNA gene sequencing was performed using the Nanopore sequencing platform, enabling comprehensive profiling of the microbial populations present in the samples. As models of MNPLs, two commercial polystyrene nanoplastics (PS-NPLs, 61.20 and 415.22 nm) and one lab-made polylactic acid nanoplastic (PLA-NPLs, 463.90 nm) were selected. As a positive control, zinc oxide nanoparticles (ZnO-NPs) were used. The observed findings revealed that exposure to MNPLs induced notable alterations in gut microbiota, including a reduction in bacterial abundance and shifts in species composition. These results suggest that MNPLs exposure can lead to microbial dysbiosis and potential gut health disruptions through its interaction, either with the gut epithelial barrier or directly with the resident microorganisms.