Simultaneous determination of type A, B and D trichothecenes and their occurrence in cereals and cereal products

Abstract

A sensitive LC–MS/MS method for the simultaneous determination of type A, B and D trichothecenes in cereals is presented. The limits of detection ranged between 0.1 and 0.7 µg kg⁻¹ for all analytes. The method was applied to 289 representatively drawn samples of wheat, rye and oat products. Ninety-four percent of the wheat samples (n = 130), 95% of the rye samples (n = 61) and 100% of the oat samples (n = 98) were contaminated with the type A trichothecenes T-2 and HT-2 toxin. Median levels of T-2/HT-2 (sum of the toxins) were 0.91, 0.53 and 8.2 µg kg⁻¹, respectively. Highest levels were found in wheat bran (24 µg kg⁻¹), rye kernels (3.1 µg kg⁻¹) and oat flakes (85 µg kg⁻¹). All wheat and rye samples and 75% of the oat samples were contaminated with the type B trichothecene deoxynivalenol. Median levels of this toxin were 23, 15 and 0.53 µg kg⁻¹, respectively. Highest levels were found in wheat bran (1160 µg kg⁻¹), rye kernels (288 µg kg⁻¹) and oat flakes (55 µg kg⁻¹). The type B trichothecene nivalenol was detected in 67% of the wheat samples, in 3% of the rye samples and in 24% of the oat samples with highest levels in wheat bran (96 µg kg⁻¹), rye kernels (1.8 µg kg⁻¹) and in oat flakes (17 µg kg⁻¹), respectively. Levels of other type A and B trichothecenes played a minor role, although the rates of contamination were often high. Neither macrocyclic type D trichothecenes (satratoxin G and H, verrucarin A, roridin A) nor diacetylverrucarol and verrucarol (type A trichothecenes), were detected in any of the samples.

Keywords:

• chromatography
• LC/MS
• trichothecenes
• cereals and grain
• T-2 toxin
• satratoxin G

Acknowledgements

The authors wish to thank the Bavarian State Ministry of the Environment, Public Health and Consumer Protection as well as the H. Wilhelm Schaumann Foundation for the financial support. Also thanks to the teams of the mycotoxin laboratories for their unhesitant help and labour in grinding, homogenization and preparation of the samples and to Stefan Asam and Michael Rychlik for conducting comparison measurements.