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. (c) 2007 Elsevier Ltd. All rights reserved.