Oral exposure to PLA microplastics induces time-dependent nanotoxicity via the gut-liver axis.

With the increasing prevalence of microplastic pollution in the environment, concerns over its potential health risks have intensified. In this study, metabolomics and microbiomics approaches were utilized to conduct multi-organ and multi-omics studies. We investigated the time-dependent nanotoxicity of polylactic acid microplastics (PLA MPs) and explored their impact on systemic metabolism as well as gut microbiota. Short-term exposure to PLA MPs induced inflammation and altered gut microbiota composition, followed by metabolic disturbances in the liver and jejunum. However, prolonged exposure triggered adaptive changes in microbiota and metabolism, gradually restoring a new homeostasis specifically formed in response to sustained external stress. This research emphasizes the adaptability of the organism and highlights the critical need for further exploration into the long-term health risks of microplastic exposure, even with biodegradable plastics.