Figure 15: Mass fractions (ng/mg) of monomer (styrene) and PS oligomers in the frass from PS. biodegradation by _Tenebrio molitor_ larvae. 10.3. Elemental Metabolomics for Honey Authentication S. A. Drivelos 1, G. Danezis 1, M. Halagarda 2, S. Popek 2 and C. A. Georgiou 1,*  
1 Chemistry Laboratory, Department of Food Science and Human Nutrition, Agricultural University of Athens, 75 Iera Odos, 118 55 Athens, Greece  
2 Department of Food Product Quality, Cracow University of Economics, ul. Sienkiewicza 5, 30-033 Krakow, Poland  
* Correspondence: cag@aua.gr  
Elemental metabolomics concerns food safety and quality. Utilization of elemental profile promotes authenticity and leads to useful markers such as rare earth elements. Elemental profiles have proved reliable indicators for geographical origin determination in many cases and furter they could provide information on genetic origin. Processing methods are also related to elemental fingerprints. Omics technologies harness the impressive power of high-resolution mass spectrometry (HRMS) [1]. Although REEs and precious metals have great potential for determination of geographical origin, they have not been studied extensively. Increased interest in rare earths as authentication markers will grow stronger in the near future. Trace and rare earth elements of 93 honeys of different botanical type, origin, and production method have been studied through ICP-MS. Information obtained using rare earths and trace elements were utilized via chemometric evaluation for the classification of honey samples. Discriminant Analysis (DA) was successful for botanical type and geographical origin classification while Cluster Analysis (CA) was successful only for botanical type. Through Probabilistic Neural Network (PNN) analysis, 85.3% were correctly classified by the network according to their geographical origin and 73.3% according to production method, organic or non-organic. A Partial Least Squares (PLS) model was constructed, giving a prediction accuracy of more than 95%. This study shows that an elemental profile could discriminate honey according geographical and botanic origin. This is an exploratory study pointing out the value of a large-scale sampling study. To explain the incapability of elemental profile to discriminate honey production method, a study on the elemental content of floral nectars and their changes along pesticides use is required [2]. ## References  
* (1) Danezis, G.P. ; Georgiou, C.A. Food quality, traceability and Foodomics. In _Comprehensive Foodomics_; Cozzolino, D., Cifuentes, A., Eds. ; Elsevier: Amsterdam, The Netherlands, 2021; pp. 244-257. * (2) Drivelos, S.A.; Danezis, G.P. ; Halagarda, M.; Popek, S.; Georgiou, C.A. Geographical origin and botanical type honey authentication through elemental metabolomics via chemometrics. _Food Chem._**2021**, _338_, 127936. * (3)_4. Advanced and Comprehensive Screening Methodologies for the Monitoring of Intentionally and Non-Intentionally Added Substances in Food Contact Materials C. Kanakaki *, E. Mermingi and N. Thomaidis Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 157 71 Athens, Greece
* (4) Correspondence: ckanakaki@chem.uoa.gr  
Packaging has become an indispensable element in the food manufacturing process, as it protects the food from, e.g., light and microbial contaminations, improving the self-life and stability of products during storage. However, it has been found to represent a source of contamination itself through the migration of substances from the packaging into food. The identification of these substances is an issue that deserves great attention to assure food quality and consumer safety. Aiming the comprehensive screening of intentionally and non-intentionally added substances (IAS and NIAS) in food contact materials (FCMs), GC-MS/MS, and GC-APCI-QTOFMS methods were developed, for the target screening of volatile migrants.