John Lee's Biography

The contamination of food with natural toxins is one of the most severe problems in food safety. Plant toxins, like the pyrrolizidine alkaloids (PAs), are produced by many plant species of the families Asteraceae, Boraginaceae, and Fabaceae.  PA containing plants occur worldwide in nearly every habitat, and food contamination typically occurs when weeds are inadvertently mixed with crops during harvesting. On the field or during transport and storage, food products are also susceptible to contaminations with mycotoxins. Mycotoxins are toxic secondary metabolites of fungi and they are a severe problem for grain production causing major financial damages each year. There is a growing interest in methods for the accurate quantitation of regulated and emerging toxins and for the screening of many toxins to identify contaminations in unlikely matrices and to grow the knowledge about the occurrence of emerging toxins. In this presentation we will show fast and accurate quantitation methods for regulated mycotoxins and the most important pyrrolizidine alkaloids using UHPLC/MS/MS. Both methods were successfully validated for a couple of food matrices and results obtained for reference materials and samples from local markets will be shown.

In addition we will present the use of a newly available accurate mass database and spectral library containing entries for more than 450 mycotoxins and related metabolites with accurate mass spectra for more than 300 compounds including both polarities and all major adduct species. Samples were analyzed by UHPLC/QTOF/MS using target MS/MS as well as All Ions MS/MS acquisition. This work demonstrates the value of both acquisition modes combined with an efficient data analysis workflow, and the new Mycotoxins and related Metabolites Personal Compound Database and Library (PCDL) for the screening and verification of mycotoxins in complex matrices.