Impact of microplastics and nanoplastics on human Health: Emerging evidence and future directions

Plastics are extensively used across industries, leading to microplastic (MPL) and nanoplastic (NPL) contamination in ecosystems. Exposure to these particles occurs primarily through ingestion, inhalation, and dermal contact, raising significant human health concerns. This review critically evaluates recent advancements in understanding the human health impacts of MPLs/NPLs, focusing on their routes of exposure including ingestion, inhalation, and dermal contact, and the mechanisms of cellular uptake and toxicity. While MPL/NPL pollution is a well-recognised environmental hazard, the conclusive evidence linking their exposure to specific health outcomes in humans remains limited. We discuss methodological gaps in assessing their toxicological impacts, particularly in vitro models, and the need for more sophisticated in vivo studies to simulate real-life exposures. Future research directions, including the exploration of the corona formation on MPL/NPL particles and its influence on cellular interactions, are outlined to bridge existing knowledge gaps.