Molecular model of ochratoxin A, a toxin produced by Aspergillus ochraceus, A. carbonarius and Penicillium verrucosum. It is one of the most abundant food-contaminating mycotoxins. It is also a frequent contaminant of water-damaged houses and of heating ducts. Humans may be exposed to it through consumption of contaminated foods, particularly grain and pork, coffee, wine grapes, and dried grapes. Molecular formula: C20 H18 Cl N O6; Molar mass: 403.81 g/mol; Carbon: gray; Hydrogen: light cyan; Chlorine: yellow; Nitrogen: blue; Oxygen: red.