Occurrence, Health Risks and Methods of Analysis for Aflatoxins and Ochratoxin A

The most frequent toxigenic fungi in the Europe are Aspergillus, Penicillium and Fusarium species. They produce aflatoxin B1 transformed into aflatoxin M1 found in the milk, as well as Ochratoxins and Zearalenone, Fumonisin B1, T-2 toxin, HT-2 toxin and deoxynivalenol (vomitoxin), which are of increasing concern in human health. These mycotoxins are under continuous survey in the Europe, but the regulatory aspects still need to be set up and/or harmonised at the European level. They are found in foodstuffs and are not destroyed by normal industrial processing or cooking since they are heat-stable. Some of their metabolites are still toxic and may be involved in human diseases. Their toxic effects (liver, kidney and haematopoietic toxicity, immune toxicity, foetal toxicity, teratogenicity, and mainly carcinogenicity) are mostly known in experimental models. Chemical assays are of major importance for the determination of mycotoxins. Generally, all chemical methods for the analysis of mycotoxins include the basic steps of extraction, clean-up, separation, detection, quantification and confirmation of identity. The various approaches that exist for the determination of nephrotoxic mycotoxins, and in particular the ochratoxins are discussed below. This paper gives an overview of chromatographic methods used for the determination of aflatoxin and ochratoxin A (OA) in animal and human tissues and fluids. These methods are needed for monitoring studies of OA occurrence in the food chain and for studies dealing with the OA carry-over. The review includes sampling, sample storage, extraction, spiking procedures, clean-up, detection and determination, and confirmation procedures.