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The method of determination of ochratoxin A in some spices: coriander, cloves, ginger, paprika, black pepper was described. Depending on kind of matrix, extraction with metanol/water (80/20) or with solution of 1% NaHCO3 and several variants of clean-up on IAC columns were investigated. The most useful extraction solvent appeared water solution of 1% NaHCO3. In case of cloves only, none of the methods of extraction and clean-up variants was appropriate. The mean recovery of the method, dependent on kind of sample, was 61-82% and RSD% 1.4 and 7.8. The estimated LOD and LOQ were 0.02 and 0.06 microg/kg, respectively. In samples of spice used for method preparation, ochratoxin A was detected on the level 3.4-4.6 microg/kg.

Ochratoxin A from wheat and rye grain was extracted with acetonitrile:water (60:40). After clean-up of extracts using immunoaffinity columns (IAC), ochratoxin was determined by high-performance liquid chromatography using C18 column and fluorometric detection at 330 nm excitation and 460 nm emission. The mean recovery of ochratoxin A at fortification levels 0.1-100 microg/kg, was 74-89%. The limits of detection (LOD) and quantification (LOQ) were 0.015 and 0.025 microg/kg, respectively. The positive results were confirmed by reaction with BF3 complex in methanol.

The studies to determine the level of filamentous fungi and mycotoxins were carried out in samples of grain and grain dust during threshing of cereals by a combine harvester. High concentration of fungi was noted in grain and grain dust samples, it ranged from 5.0 to 520.0 cfu/g.10(3) and from 275.0 to 2825.0 cfu/g.10(3), respectively Allergizing and toxigenic fungi of Alternaria, Geotrichum, Cladosporium, Penicillium, Aspergillus and Fusarium species were observed in the study samples of grain and grain dust. In the samples of wheat grain, mycotoxins were also noted: moniliformin (MON), deoxynivalenol (DON) and ochratoxin A (OTA); their concentrations ranged from 0.025 to 0.088 microgram/g; 0.015-0.068 microgram/g; and from 0.0004 to 0.0008 microgram/g, respectively. The level of mycotoxins in the grain dust samples was within the range of 0.025-0.149 microgram/g-MON; 0.015-0.215 microgram/g-DON; 0.015-0.360 microgram/g-NIV; and 0.0004-0.0012 microgram/g-OTA. A significant correlation was observed between the occurrence of fungi of Fusarium species and the concentration of pathologic mycotoxins. The results confirm a considerable occupational risk among farmers engaged in grain threshing due to inhalation of pathogenic species of filamentous fungi and mycotoxins.

A trial was undertaken for determination of the average daily amount of ochratoxin A consumed with contaminated food by adults in Poland. Contamination of food with ochratoxin A was estimated to be 0.448 ng/g, and the mean level of this metabolite in human serum was 0.27 ng/cm3. These values showed a considerable similarity when they were analysed by simplified conversion factors of Mortensen et al.