Following model validation criteria, features are included in the finalised, aggregate response upon which a model is also fit, and factor optima are provided. A validated model indicates that each grape marc spirit sample is analysed in an optimal manner, thus providing opportunities for sample classification marker discovery. This work was supported by the project \"Foodomics-GR\" (MIS 5029057), funded by the Operational Programme NSRF 2014-2020 and co-financed by Greece and European Regional Development Fund. The authors thank A. Zotou and Prof. E. Souforelos of Aristotle University of Thessaloniki for providing the grape marc samples. ## References  
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* Kalogeropoulou 1,* Cosma 1 and T. Albanis 1,2
* Laboratory of Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece
* Institute of Environment and Sustainable Development, University Research Center of Ioannina (URCI), 45110 Ioannina, Greece
* Correspondence: aggelkaloge@yahoo.gr  
Emerging pollutants (EPs) are chemical substances widely produced and consumed due to the rapid urbanization of free land, technological growth, and human quality of life [1]. Agricultural and urban areas emit emerging contaminants potentially hazardous to the aquatic environment that may also affect human health, such as Pharmaceutical Active Compounds (PhACs) [2,3]. Sediments play an important role in aquatic ecosystems as habitats for a variety of aquatic organisms, and they are regarded as a primary sink of organic pollutants. Aquacultures around the world are gaining more interest due to their fast growth food production and, as a result, it is essential to investigate the occurrence, distribution, and fate of PhACs in the aquatic ecosystems [4]. Thus, the aim of the present study was to develop a multi-residue analytical method for the determination of traces of 22 multiclass pharmaceuticals in aquaculture sediments. The procedure, based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method, followed by ultrahigh-performance liquid chromatography-high-resolution linear ion trap/Orbitrap (LTQ Orbitrap) mass spectrometry, operated in positive ionization mode. In order to optimize process efficiency, three different methods (original, acidified, and buffered) were tested, using different solvents, extraction salts, sediment amount, and clean-up salts, as well. A matrix-matched calibration approach and isotopically labeled internal standards were employed for quantification and correction of matrix effects. The optimized method was validated in terms of linearity, recovery, precision, limit of detection (LOD) and quantification (LOQ), and matrix effects (ME). Finally, the validated method was successfully applied to real samples.