Mycotoxins produced by Fusarium genus in maize: determination by screening and confirmatory methods based on liquid chromatography tandem mass spectrometry

A confirmatory method for fusariotoxin analysis in maize meal, based on liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS), was developed, and compared with a previously published screening method, based on the same technique. By eluting selectively from a Carbograph-4 clean-up cartridge trichothecenes, fumonisins and macrocyclic lactones, and optimizing LC–MS/MS conditions for every chemical class, a sensitive and reliable determination was performed. Method quantification limits for confirmatory and screening methods were in the range 0.001–0.019 mg/kg and 0.003–0.125 mg/kg, respectively.Maize samples collected from four different hybrids grown in five experimental field trials were analyzed with both screening and confirmatory procedures. In most of the samples, fumonisin B1–3 were revealed with a concentration above 2 mg/kg. Zearalenone was found at a higher level than 0.5 mg/kg in three samples, and nine samples were found positive for this toxin only with the confirmation method, being contaminated at levels below 0.008 mg/kg. Among trichothecenes B only deoxynivalenol was found twice at a concentration over 1 mg/kg, whereas fusarenon X was never revealed. Trichothecenes A were present at a concentration lower than 0.015 mg/kg.