Ochratoxins are mycotoxins produced by several species of Aspergillus and Penicillium. Ochratoxin A is the most economically important form of ochratoxin; ochratoxins B and C are less toxic and less common. Ochratoxins may be transferred through milk, blood, and meat. Ochtratoxin poisoning is thought to be the cause of a chronic kidney disease in humans known as Balkan endemic nephropathy. Recent studies have provided a link between ochratoxin exposure and human testicular cancer in Europe.Ochratoxin contamination is economically important in cereal grains, grapes, coffee, tree nuts, and figs. Penicillium verrucosum is the leading cause of ochratoxin contamination of cereal grains in temperate climates. Grapes, raisins, and even wines may become contaminated with ochratoxins produced by Aspergillus carbonarius, the principal causal agent of grape black mold [Movie 1]. A number of Aspergillus spp. may cause ochratoxin contamination in green and processed coffee, including A. ochraceus, A. carbonarius, and A. niger. Tree nuts and figs may be infested with A. ochraceus and A. melleus, the leading producers of ochratoxins in these commodities.