Microplastics in our diet: a focus on intestinal health

Because plastics exhibit various functional properties, they play a pivotal role in our daily life. However, their massive use has led to a sharp increase in plastic pollution worldwide, generating after degradation massive amounts of small-sized microplastics. Their presence in the environment but also in food products and packaging has revealed a potential threat to human health. In this review, a special emphasis is given on the human gastrointestinal tract, as a portal of entry but also first barrier for microplastics. First, we summarize the charac-teristics of ingested forms (origin, occurrence, size, shape, polymer type, surface properties) and give the current state of knowledge on human oral exposure to microplastics. Then, we highlight the physicochemical transformations of microplastics during digestion. Afterwards, we detail their potential impact on gut homeostasis disruption, via the three protagonists, epi-thelium/mucus/gut microbiota, considering in vitro and in vivo studies in rodents. Finally, this review underlines future directions about microplastics in the field of human intestinal health. Particular emphasis is given to the unmet need of developing robust in vitro gut models to adequately simulate human digestive physiology for better health risk assessment related to microplastics. (c) 2022 Societe francaise de nutrition. Published by Elsevier Masson SAS. All rights reserved.