Microplastics Accumulation in Clearance-Associated Organs: An Overview of Potential Health Implications

The widespread use and improper disposal of plastics have made them ubiquitous contaminants that can potentially adversely affect both the environment and human health. The impact of microplastics (MPs)—plastic particles less than 5 mm in size—has been widely studied in marine and terrestrial environments; however, their potential effects on human health have only recently begun to receive attention. Although once considered inert materials, MPs exposure in laboratory animals is now linked to inflammation, immunological responses, lipid and energy metabolism alterations, mitochondrial damage, and other disorders. Since clearance-associated organs such as the liver, kidneys, spleen, lungs, and the gastrointestinal tract play a critical role in processing, metabolizing, filtering, and excreting toxins and foreign substances, they are particularly vulnerable to MPs exposure and accumulation. The increasing intake of plastics, primarily via ingestion and inhalation, raises concerns regarding their fate and retention in these organs, potentially leading to long-term health impacts. This review provides an overview of recent findings regarding MPs accumulation in clearance-associated organs and possible health impacts, and discusses future outlook and potential strategies for mitigating the health risks associated with nano- and microplastics exposure.