Mycotoxins are low molecular weight, secondary metabolites of fungal (mold) compounds which are increasingly recognized as a global health threat given their role in precipitating both acute and chronic adverse health outcomes. Common fungi sources of mycotoxins include species such as Fusarium, Aspergillus, Penicillium, Alternaria, and Claviceps. To date nearly 400 potentially toxic mycotoxins produced by more than 100 fungi species have been identified, although research has focused on the most toxigenic in the public health, veterinary, and agricultural realms. Exposure to mycotoxins may occur through a variety of routes such as inhalation, ingestion, and dermal contact from airborne mold spores, food contamination, and water-damaged building environments. Susceptibility to mycotoxins is influenced by a patient’s age, sex, presence of other underlying diseases and/or exposures, nutritional status, and length of exposure. While mycotoxin toxicity may present as an acute state marked by rapid onset with potential life-threatening illness, most of the negative health impacts observed in the developed (Western) world are due to chronic, low-dose exposures. These long-term exposures have been associated with a variety of systemic effects (mycotoxicoses) in both humans and animals – and most commonly manifest as nephrotoxicity, hepatotoxicity, immunosuppression, carcinogenicity, and teratogenicity.