MYCOTOXINS IN INGREDIENTS OF ANIMAL FEEDING STUFFS - II - DETERMINATION OF MYCOTOXINS IN MAIZE AND MAIZE PRODUCTS

Analytical methods have been developed for the reliable detection and estimation of 22 mycotoxins in maize gluten and other maize products u sed in the animal feed industry. The mycotoxins are aflatoxins B-1, B- 2, G(1) and G(2), ochratoxins A and B, citrinin, cyclopiazonic acid, z earalenone, sterigmatocystin, deoxynivalenol, nivalenol together with seven related trichothecene mycotoxins, fumonisins B-1 and B-2 and mon iliformin. For most of the mycotoxins, recoveries obtained were 60% ol greater and reproducibility data br ere better than +/-40%. rn genera l, the analysis of maize gluten proved more difficult than for other m aize products. In total 40 samples of maize gluten, and 27 samples of other maize products were examined. Aflatoxins were not found above th e reporting limit (1-5 mu g/kg) in any sample while ochratoxin A was d etected in only two samples of maize gluten at 2 mu g/kg. No sterigmat ocystin or cyclopiazonic acid were detected although the limits of det ection for these toxins were poor. Twenty percent of maize gluten samp les contained zearalenone at up to 500 mu g/kg while all other maize p roducts also contained this mycotoxin. Highest levels occurred in scre enings and meal while the lowest amounts were in flaked maize and germ . Many samples contained a multi-toxin mixture of trichothecenes, fumo nisins and moniliformin. The most highly contaminated samples of maize screenings and maize meal contained a mixture of zearalenone, deoxyni valenol, nivalenol, fumonisin B-1 and B-2, moniliformin, each in mg/kg amounts and lower amounts of other trichothecenes such as 15-acetoxy deoxynivalenol, HT-2 toxin and T-2 toxin. Fumonisins occured in all ex cept two gluten samples and occured up to a level of 32 mg/kg in maize screenings, 13 mg/kg in maize and 8 mg/kg in maize germ.