Engineered nanomaterials and the microbiome: Implications for human health

Abstract

The composition of the gut microbiome is highly variable and can be altered by external substances including engineered nanomaterials (ENM). Solid particles are abundantly present in our food including intentionally produced particles in the size-range below 100 nm, which are termed nanoparticles. ENM inter alia includes nanoparticles and their agglomerates which occur as food additives, and contaminants in human food and drinking water. In the past five years, more than thirty studies on the effects of ENM on the microbiome were published. These are summarized and reviewed here. Clearly, ENM can affect the gut microbiome in diverse ways. Many studies are exploratory and do not always show unanimous effects; few studies actually demonstrate a link to adverse effects on the host. Based on these data, future studies can be designed to allow for the assessment of hazards and risks of ENM via microbiome changes. We are discussing studies providing such information and needs for future studies to understand and assess ENM's impact on the gut microbiome and then on human health.