Exposure of polystyrene microplastics induces oxidative stress and physiological defects in Drosophila melanogaster

Background: Microplastics are emerging contaminants in aquatic and terrestrial environments. Here, we used the fruit fly (Drosophila melanogaster) as model organism to study the adverse effects of polystyrene microplastics (PS-MPs). Methods: The computational study of styrene-protein interactome revealed enrichment of oxidative stress related pathways. Therefore, we tested the in-silico data by analysing the toxicity of PS-MPs via dietary exposures to 5g/l and 10 g/l doses on Drosophila melanogaster. Results: At both of these doses there was significant increase in oxidative stress as revealed by lipid peroxidase assay. Furthermore, PS-MPs significantly reduced climbing ability of adult flies and distribution pattern of pupal positioning during development. Conclusion: Overall, dietary exposures of PS-MPs caused toxicity in the fruit flies. This study establishes a baseline understanding of the impacts of PS-MPs to the fruit fly and motivates the need for further work focusing on naturally weathered plastic debris.