The global rise in single-use plastic products and waste has raised concerns about microplastic and nanoplastic pollution in the environment. Microplastics are particles less than 5 mm in diameter, while nanoplastics are even smaller. Both pose potential risks to human health. Emerging research suggests that nanoplastics accumulate in carotid artery plaques, which may increase the risk of cardiovascular events, such as heart attacks and strokes. However, the pathways by which nanoplastics enter the human bloodstream remain poorly understood.
In our study, we investigated how nanoplastics enter mammalian cells and circulate in the body using both ex vivo cellular models and in vivo mouse models. Our results indicate that nanoplastics can enter the bloodstream of mice through oral ingestion. At the cellular level, gut epithelial cell lines efficiently internalize nanoplastics via receptor-mediated endocytosis. Using mass spectrometry, we identified potential receptors that interact with nanoplastics. Moving forward, our research will focus on characterizing these receptors and understanding the pathways that nanoplastics use to enter human gut epithelial cells.