Mycotoxins, the secondary metabolites of fungal species, are the most frequently occurring natural food contaminants in human and animal diets. Risk assessment of
mycotoxins focused as yet on their mutagenic, genotoxic and potential carcinogenic effects. Recently, there is an increasing awareness of the adverse effects of various
mycotoxins on vulnerable structures in the intestines. In particular, an impairment of the barrier function of the epithelial lining cells and the sealing
tight junction proteins has been noted, as this could result in an increased translocation of
luminal antigens and pathogens and an excessive activation of the immune system. The current review aims to provide a summary of the available evidence regarding direct effects of various
mycotoxins on the intestinal epithelial barrier. Available data, based on different cellular and animal studies, show that food-associated exposure to certain
mycotoxins, especially
trichothecenes and
patulin, affects the intestinal barrier integrity and can result in an increased translocation of harmful stressors. It is therefore hypothesized that human exposure to certain
mycotoxins, particularly
deoxynivalenol, as the major
trichothecene, may play an important role in etiology of various chronic intestinal inflammatory diseases, such as
inflammatory bowel disease, and in the prevalence of
food allergies, particularly in children.