Mycotoxins, toxic fungal secondary metabolites, are one of the main food safety threats worldwide. Co-occurrence of multiple mycotoxins in one crop, as well as effects of climate change, complicate this research field. Moreover, mycotoxins can be modified by fungi, plants, animals and humans, or through food processing which further hinders their analysis and control. Sensitive on-site detection of mycotoxins and their modified forms in various matrices is highly needed. Therefore, both quantitative (ELISA, biosensors) and qualitative (lateral flow dipsticks) systems for (multi)mycotoxin detection are being developed. Examples such as multiplex strip tests and lateral flow devices using quantum dots as labels will be presented. LC-MS/MS methods are mainly used as confirmatory and can be implemented for multi-mycotoxin analysis, including modified forms. Moreover, high resolution mass spectrometry is of great interest as it is an invaluable tool to discover unknown secondary fungal metabolites and identify fungal species; to study degradation products and modified forms of mycotoxins as a result of processing techniques and use of detoxifying enzymes or microbes; and to unravel the human and animal mycotoxin metabolism. Human mycotoxin exposure can be determined both indirectly (based on the combination of chemical analysis of foodstuffs and food consumption data) and directly by the determination of exposure biomarkers and, mycotoxin biotransformation products, in biological fluids, such as urine, blood or faeces. In recent years many efforts have been put in the development of ultra-sensitive multi-mycotoxin LC-MS/MS methods for analysis of mycotoxin exposure biomarkers. However, still many gaps in our understanding of the human mycotoxin metabolism exist. Moreover, mycotoxins are only one group of environmental contaminants humans are exposed to. The exposome concept attempts to measure all non-genetic exposures from conception throughout the life course. The presentation will also highlight the analytical challenges that this will bring.

Aspergillusmycotoxins belong to the most important and toxicologically relevant contaminants in food and feed worldwide. Especially aflatoxin B1 (AFB1) is in the focus of science, risk assessment and management since many years. Although it iswell documented that other mycotoxins formed by Aspergillusspeciesare of similar importance for food safety, these compounds have been rarely investigatedin detail[1]. Thus, the presentation will provide particular insight on the analysis, occurrence and impact of biosynthetic precursors and metabolites of “the mycotoxin” AFB1.Additional to AFB1,its principalbovine metabolite, the monohydroxylated derivative aflatoxin M1 (AFM1), is regulated e.g. in milkin many countries. AFM1 is proven to exert similar, butless potent toxic effects compared to AFB1[1].Besides dairy cattle also other livestock with different metabolic properties might be exposed toAFB1 contaminated feed. Particularly, for edible insects whose utilisation increases constantly, the elucidationof potential transformation products and accumulation of natural contaminants is crucial for (novel) food safetyevaluation. Results from model and in vitro investigations show that for AFB1 the transfer and accumulation in yellow mealworm larvae islimited. However, inter-species comparison reveals the formation of at least one still uncharacterised metabolite in the insects[2].Independent of metabolic specificities during AFB1 transfer in the food chain, further potentially harmful derivatives should be considered as emerging contaminants. Forintermediates of the fungal AFB1 biosynthesis such as sterigmatocystin (STC) and versicolorin A recent studies provide proof for both, a significant toxicity as well as frequent occurrence in food[3]. Recent data on LC-MS/MS method development and quantification in different commodities will be presented and discussed in the presentation. Unlike for AFB1 where only the phase-I metabolite AFM1 is found in milk and milk products, for STC only the parent compound is reported to occur e.g. in cheese[4]. Despite structural similarities, comparable toxicityand common toxin forming fungi for AFB1 and STC, it is not feasible to suggest the occurrence or metabolic transformation of STC based on AFB1 data. By contrast, it becomes obvious that for emerging contaminants it is mandatory to separately elucidate the species-specificmetabolism as well as food technological behaviourby combination of different analytical tools. For “the mycotoxin” AFB1, the more comprehensive evaluationof its emerging companions might add a new chapter to the well-knownstory.

Pyrrolizidine alkaloids are carcinogenic plant toxins, which may enter the food chain via different routes and thus can contaminate various food products such as herbs, tea or honey. They are commonly analysed by LC-MS/MS, whereby their correct identification and quantification is challenging due to several obstacles, including sample inhomogeneity, pronounced matrix effects and low-ppb concentrations. A further challenge is posed by the fact that many pyrrolizidine alkaloids are isomeric to one another, being either structural isomers or stereoisomers. These isomers share some or even all MS/MS transitions; however, the relative intensities of the product ions may vary significantly, complicating quantification and impeding confirmation by MS/MS transition ratios. Thus, chromatographic separation is essential to differentiate between the isomers and allow sound quantification. However, with the ever-growing number of analytes the simultaneous separation of the various isomers becomes more and more challenging. In-depth investigations concerning the chromatographic and mass spectrometric behaviour (separation on different columns and fragmentation patterns, respectively) of more than 40 pyrrolizidine alkaloids were carried out to provide essential input for developing a method allowing the specific qualitative and quantitative analysis of as many pyrrolizidine alkaloid isomers as possible. The majority of studied isomers could finally be chromatographically resolved on a C18 column within less than twenty minutes, with additional lycopsamine isomers being baseline separated on a phenylhexyl column. For the remaining co-eluting isomers it was confirmed that the mass spectrometric behaviours are comparable, thus allowing for a summary assessment without making an error concerning the quantitative results. Finally, data from various food products from the Austrian market will be presented, highlighting which isomers frequently occur in practice and thus fully justify analytical efforts for their specific analysis.

Food contains thousands of different compounds. The largest part of them is unknown. Contaminants of unknown identity can be found among them. These chemicals may originate from raw materials and manufacturing processes along the global production chain to final packaging and storage. Not always characterized and often present as multi-component mixtures, it is difficult to determine the health significance of these chemicals. Standard risk assessment methods are often not readily applicable, and this uncertainty about safety is a concern for policymakers, industry, and the public. A concept is shown for prioritization of chemicals. Two different disciplines (chemistry and biology) are combined to obtain image-based effect profiles [1]. In comparison to reference samples, these visualize in a non-targeted way, for example, genotoxic [2], cytotoxic [3], neurotoxic [4], and hormonal [5] active contaminants in food. Metabolism in terms of digestion and detoxification in the liver can also be simulated on the same surface [7], which is important additional information for risk assessment. For characterization of active zones, a generic 14 D hyphenation was developed that can couple chromatography/detection dimensions as needed [5] and record mass spectra fully automated as sequence directly from the bioautogram [8]. A high density of information is useful for their characterization or identification. Miniaturization to an open-source all-in-one 2LabsToGo system [9] and sustainability of the method are also important keys for more efficiency.