Ochratoxin A is a nephrotoxic fungal metabolite (mycotoxin) occurring in foodstuffs. The compound is causally associated with mycotoxic porcine nephropathy, a disease comparable with a human kidney disease, Balkan endemic nephropathy. A preliminary survey of homeproduced foodstuffs in areas of Yugoslavia revealed that contamination with ochratoxin A is more frequent in an area where Balkan endemic nephropathy is prevalent (endemic area) than in an area where this disease is absent. This indicates higher exposure to foodborn ochratoxin A in the endemic area. Thus further evidence is provided supporting the hypothesis that ochratoxin A is a disease determinant of Balkan endemic nephropathy.