HIDDEN IN THE HEIGHTS: NON-TARGET SCREENING OF CECs IN MOUNTAIN SNOW AND WATER

This work is part of the IN2AQUAS project financed within the EU Horizon program and focused on securing water quality from remote areas to the tropical belt. The work is therefore focused on the identification of contaminants of emerging concern (CECs) through untargeted approaches based on UHPLC coupled to high resolution mass spectrometry (HRMS). Two comprehensive sampling campaigns have been carried out, targeting snow and water in the Monte Bianco area (Valle d’Aosta, Italy) and around Courmayeur (Valle d’Aosta, Italy) to investigate the presence of CECs. The collected samples underwent different pre-treatment procedures to verify the best protocol for non-targeted analysis of water samples able to provide the widest possible range of detected analytes. Lyophilization and solid-phase extraction (SPE) were exploited; SPE was applied with three different cartridges for the extraction, namely —HLB, WAX, and MAX—to capture a wide range of contaminants. The processed samples were then analyzed using ultra-high-performance liquid chromatography coupled with mass spectrometry (uHPLC-MS) equipped with an Orbitrap detector (Exploris 120, Thermo Scientific). For the identification and quantification of the analytes, Compound Discoverer (Thermo Scientific) and MZmine 3.0 were applied. Our findings reveal the presence of various CECs, highlighting the impact of anthropogenic activities even in remote and seemingly untouched environments. These findings underscore the importance of continuous monitoring and advanced analytical approaches to detect and address the spread of contaminants even in high-altitude regions