Muriel Mercier-Bonin is INRAE research director and deputy director of the Toxalim unit in Toulouse. She began her research activities at the Toulouse Biotechnology Institute at INSA Toulouse, studying the mechanisms of interaction between micro-organisms and surfaces. She then joined the MICALIS unit in Jouy-en-Josas to study the structural and functional role of mucus, a key player in intestinal homeostasis. For several years, as part of Toxalim's Neuro-Gastroenterology and Nutrition team, she has led a research theme on the interrelationships between food contaminants, microbiota, mucus and the host in the digestive tract, under physiological and pathophysiological conditions. Since 2018, it has focused on the impact of micro- and nano-plastics on human health, with a focus on the intestinal ecosystem.