Detection of trace levels of trichothecene mycotoxins in environmental residues and foodstuffs using gas chromatography with mass spectrometric or electron-capture detection.

Methods are described for the simultaneous detection of a wide range of trichothecenes, including the most polar ones and some macrocyclics, using either gas chromatography-mass spectrometry with selected ion monitoring, or gas chromatography with electron-capture detection. Trichothecenes were extracted directly from the various matrices, or from Clin Elut columns, and cleaned up on Florisil Sep-Pak cartridges. Macrocyclics and neosolaniol were detected after hydrolysis to verrucarol and T-2 tetraol respectively. For optimum sensitivity (0.5-10 ng per sample) over the range, trichothecenes were detected, both before and after hydrolysis of ester groups, as their heptafluorobutyrate derivatives using a quadrupole mass spectrometer and negative ion chemical ionisation. The use of a magnetic sector instrument with electron-impact ionisation gave comparable sensitivity for most trichothecenes, but was less useful for the simultaneous detection of verrucarol in the presence of other trichothecenes. The methods were used to detect the presence of scirpentriol, nivalenol and 15-monoacetoxyscirpendiol in sorghum from Thailand. Trichothecenes in less complex matrices could be detected, after hydrolysis, using gas chromatography with electron-capture detection.