What Gastroenterologists Should Know About Microplastics and Nanoplastics.

Global production and widespread use of plastics are increasing dramatically. With current limited recycling and recovery options, microplastics and nanoplastics (MNPs) persist in the natural environment. Due to their ubiquity, human exposure to MNPs is inevitable. In addition to their inherent toxic effects, MNPs can adsorb harmful contaminants and act as vectors for microorganisms, compounding toxicological effects. After entering the body, bioaccumulation occurs in several tissues and organs, including the liver and the gastrointestinal (GI) tract. Proposed clinical effects of MNP absorption include endocrine disruption, alteration of the GI microbiome, and promotion of chronic inflammatory conditions. MNPs can also influence energy metabolism, activate inflammatory pathways, and increase oxidative stress leading to apoptosis. The GI tract is a major site of bioaccumulation for the MNPs in animals and humans. In this editorial, the current understanding of how MNPs are processed is discussed. Discussion on MNP effects on internal microflora, and their proposed role in developing inflammatory bowel diseases, MNP toxicokinetics, and their significance in health and disease are also reviewed. There is a need to understand the impact of MNP exposure on gut health and gut microbiota and identify current research gaps.