Multi-mycotoxin stable isotope dilution LC-MS/MS method for Fusarium toxins in cereals

A multi-mycotoxin stable isotope dilution LC-MS/MS method was developed for 14 Fusarium toxins including modified mycotoxins in cereals (deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, HT2-toxin, T2-toxin, enniatin B, enniatin B1, enniatin A1, enniatin A, beauvericin, fusarenone X, nivalenol, deoxynivalenol-3-glucoside, and zearalenone). The chromatographic separation of the toxins with particular focus on deoxynivalenol and deoxynivalenol-3-glucoside was achieved using a C₁₈-hydrosphere column. An expedient sample preparation method was developed that uses solid-phase extraction for the purification of trichothecenes combined with zearalenone, enniatins, and beauvericin and provides excellent validation data. Linearity, intra-day precision, inter-day precision, and recoveries were =0.9982, 1-6 %, 5-12 %, and 79-117 %, respectively. Method accuracy was verified by analyzing certified reference materials for deoxynivalenol, HT2-toxin, and T2-toxin with deviations below 7 %. The results of this method found barley malt samples from 2012, 2013, and 2014 frequently contaminated with high concentrations of enniatin B, deoxynivalenol, and its modified mycotoxin deoxynivalenol-3-glucoside. Samples from 2012 were especially contaminated. Fusarenone X was not detected in any of the analyzed samples.