PET microplastics affect human gut microbiota communities during simulated gastrointestinal digestion, first evidence of plausible polymer biodegradation during human digestion

Alba Tamargo,Jose F Fernández,Miguel A Bañares,Julián J Reinosa,M Victoria Moreno-Arribas,Raquel Portela,Natalia Molinero,Victor Alcolea-Rodriguez

doi:10.1038/s41598-021-04489-w

Abstract

Microplastics (MPs) are a widely recognized global problem due to their prevalence in natural environments and the food chain. However, the impact of microplastics on human microbiota and their possible biotransformation in the gastrointestinal tract have not been well reported. To evaluate the potential risks of microplastics at the digestive level, completely passing a single dose of polyethylene terephthalate (PET) through the gastrointestinal tract was simulated by combining a harmonized static model and the dynamic gastrointestinal simgi model, which recreates the different regions of the digestive tract in physiological conditions. PET MPs started several biotransformations in the gastrointestinal tract and, at the colon, appeared to be structurally different from the original particles. We report that the feeding with microplastics alters human microbial colonic community composition and hypothesize that some members of the colonic microbiota could adhere to MPs surface promoting the formation of biofilms. The work presented here indicates that microplastics are indeed capable of digestive-level health effects. Considering this evidence and the increasing exposure to microplastics in consumer foods and beverages, the impact of plastics on the functionality of the gut microbiome and their potential biodegradation through digestion and intestinal bacteria merits critical investigation.

Highlights

Microplastics (MPs) are a widely recognized global problem due to their prevalence in natural environments and the food chain
Our study demonstrates that microplastic feeding affects both composition and diversity of colonic microbial communities
The studies on this field have been focused on the effect of MPs on the gut microbial communities of soil animals or mice[14,15,36,37], and to our knowledge, this is the first report about the modifications and potential effects of microplastics on human colonic microbiota

Summary

Introduction

Microplastics (MPs) are a widely recognized global problem due to their prevalence in natural environments and the food chain. The primary health effects of food-ingested plastic particles are triggered from the digestive system, causing direct damage at local level, as irritation or intestinal dysbiosis, and at systemic level[4] In this regard, Fackelmann and Sommer reviewed the link between MP-induced gut dysbiosis and host health and suggested that MPs could impact gut microbiome and that chronic exposition could lead to gut dysbiosis in several s pecies[13]. Dynamic models are more complex but closer to the physiological reality of the gastrointestinal t ract[17,18] One of these dynamic simulators is the simgi® system, a computer-controlled gastrointestinal in vitro model designed to reproduce the colonic microbiota responsible for metabolic bioconversions in the large intestine that has been employed to study the effect of different foods[19,20,21,22,23,24,25]. Dynamic simulators like simgi® have been shown to be useful to evaluate the effects on intestinal microbiota of Active Pharmaceutical Ingredients (API)[26], heavy metals[27,28] and food-use nanomaterials[29,30]

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Results

Conclusion