Determination of T-2 and HT-2 toxins in oats, barley, rye and cereal-based products by fluorescence polarization immunoassay

European intake estimates indicate that the presence of T-2 and HT-2 toxins in cereals can be of concern for human health. Oats, barley and rye have been shown to be frequently contaminated by T-2 and HT-2 toxins, with high incidence and levels of contamination. Furthermore cereal-based products have also been shown to be contaminated. Therefore, the European Commission has recommended to collect more monitoring data on the presence of T-2 and HT-2 toxins in cereals and cereal-based products in order to assess changes and trends in human and animal exposure to these mycotoxins. The development of rapid, sensitive and reliable methods for monitoring T-2 and HT-2 toxins in cereals and cereal-based products has high priority in order to protect consumer health from the risk of exposure to these toxins. Fluorescence Polarization (FP) immunoassay is a homogeneous technique that is getting attention as screening tool in food safety control due to its simplicity, rapidity, cheapness and reliability. Fluorescence polarization immunoassays have been optimized for rapid quantification of T-2 and HT-2 toxins in oats, barley, rye and cereal-based products. Samples were extracted with 90% methanol and the extract was filtered and diluted with sodium chloride solution prior to the FP immunoassay. Overall mean recoveries from spiked oats, rye, barley, pasta, oat flakes and oats crispbread ranged from 101% to 107% with relative standard deviations lower than 6%. Limits of detection (LODs) of the FP immunoassay were 70 µg/kg for oats, 40 µg/kg for oat flakes and barley, 25 µg/kg for pasta and 20 µg/kg for rye and oats crispbread. Good correlations (r > 0.953) were observed between T-2 and HT-2 toxins contents in naturally and artificially contaminated barley, oats, oat flakes and pasta samples determined by both FP immunoassay and UHPLC with immunoaffinity column clean-up. These results, combined with rapidity (less than 10 min) and simplicity of the assay, show that the optimized assay is suitable for high-throughput screening as well as for reliable quantitative determination of T-2 and HT-2 toxins in oats, barley, rye and cereal-based products.