The ochratoxins are a group of closely related fungal metabolites produced by various species of Aspergillus ochraceus as well as by Penicillium viridicatum and certain other Penicillium species. Ochratoxin-A is the most toxic of the ochratoxins and is produced in highest yield. Ochratoxin-A causes necrosis of the renal tubular epithelium of the kidney and of periportal liver cells with accompanying enteritis. Ochratoxin has been detected in commercial corn and barley, in feed grains, in dried white beans, mouldy peanuts, green coffee beans and in wine from grapes derived from particular areas. It also has been found in barley and oats associated with swine nephropathy and in tissues of these swine. Recently Maximum Levels (MLs) for Ochratoxin-A have been established in Europe legally. Depending on the products, the MLs vary from 3 to 10 µg/kg (ppb). In the Ochratoxin-A EIA-kit of Euro-Proxima an antiserum is used that cross-reacts with ochratoxin-A (100%) and with ochratoxin-B (9.3%). No cross-reactivity with coumarin and 4-hydroxycoumarin was observed. The limit of detection for Ochratoxin-A is 0.5 µg/kg (ppb).