Micro- and nano-plastics, intestinal inflammation, and inflammatory bowel disease: A review of the literature

Plastics, encompassing a wide range of polymeric materials, and their downstream products (micro- and nanoplastics, MNPs) are accumulating in the environment at an alarming rate, and they are linked to adverse human health outcomes. Considering that ingestion is a main source of MNPs exposure, the impact of plastics is particularly relevant towards intestinal inflammation and inflammatory bowel disease (IBD). However, the study of MNPs has been limited by obstacles relating to sample collection, preparation, and microplastics analysis based on optical microscopy and chemical analysis, which we detail in this review alongside potential solutions. We summarize available data on human exposure to MNPs and overall health outcomes, with particular focus on data pertaining to intestinal inflammation, microbiome perturbations, and related outcomes. We include ecologic perspectives, and human, in vitro, and animal model studies. We discuss the way forward in MNPs and IBD research, including knowledge gaps and future research. [Display omitted] •Micro- and nanoplastics (MNPs) pollution is rising globally.•Ingestion is a main source of human MNPs exposure.•MNPs are implicated in intestinal inflammation and microbiome perturbances, and may lead to inflammatory bowel disease.•Challenges in biological sample collection, preparation, and analysis impede study of MNPs.•Future MNP studies will inform disease risk, mitigation strategies, and health policy.