Ochratoxin A from a toxicological perspective

Ochratoxin A (OTA) is a widespread mycotoxin which is produced mainly by th e mould fungi Aspergillus ochraceus and Penicillum verrucosum during the st orage of cereals, cereal products and other plant-derived products such as herbs, spices, grapes, etc. By carry over from mouldy fodder, ochratoxin A is also found in pork meat, offal and sausages containing pork blood. When ingested as a food contaminant, OTA is very persistent in human beings with a blood half-life of 35 days after a single oral dosage due to unfavourabl e elimination toxicokinetics. This renders the toxin among the most frequen t mycotoxin contaminants in human blood in the EU, the US, Canada, and else where, where it has been investigated. OTA is neither stored nor deposited in the body, but heterogeneous body distribution may impose serious damage to the kidneys. The toxin was classified a 2B cancer compound, being possib ly carcinogenic for humans. It was among the strongest carcinogenic compoun ds in rats and mice. As the toxicological profile also includes teratogenes is, nephrotoxicity, and immunotoxicity, legislation authorities are current ly discussing maximal residue levels (MRL) for OTA in various foodstuffs. I n the present article arguments are presented which suggest an acceptable d aily intake (ADI) of 1.5 ng OTA/kg body weight and a much lower MRL than 5 mu g OTA/kg cereals and cereal products as has been postulated by the EU co mmission.