ΠΡΟΣΔΙΟΡΙΣΜΟΣ ΥΠΟΛΕΙΜΜΑΤΩΝ ΦΥΤΟΦΑΡΜΑΚΩΝ ΣΕ ΕΔΑΦΙΚΑ ΔΕΙΓΜΑΤΑ ΜΕ ΤΗΝ ΤΕΧΝΙΚΗ QuEChERS ΣΕ ΣΥΝΔΥΑΣΜΟ ΜΕ ΥΓΡΗ ΧΡΩΜΑΤΟΓΡΑΦΙΑ ΜΕ ΦΑΣΜΑΤΟΜΕΤΡΙΑΣ ΜΑΖΑΣ

Στην παρούσα εργασία πραγματοποιήθηκε η ανάπτυξη και η επικύρωση αναλυτικής μεθόδου για τον προσδιορισμό υπολειμμάτων φυτοφαρμάκων (ζιζανιοκτόνα, εντομοκτόνα, μυκητοκτόνα, >50 δραστικές ουσίες) σε εδαφικά δείγματα. Η μέθοδος βασίστηκε στην εφαρμογή της τεχνικής QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) σε συνδυασμό με Υγρή Χρωματογραφία Φασματομετρίας Μάζας (LC-MS). Για τη βελτιστοποίηση της μεθόδου μελετήθηκαν διάφορες παράμετροι που επηρεάζουν την «τεχνική» QuEChERS, τόσο στο στάδιο της εκχύλισης/κατανομής, όσο και στο στάδιο καθαρισμού του υποστρώματος (clean-up). Στην κατεύθυνση αυτή συγκρίθηκαν διαφορετικοί διαλύτες εκχύλισης, ποσότητες και συνδυασμοί αλάτων, καθώς και διαφορετικά προσροφητικά υλικά (C18, GCB, PSA, Florisil) για τον καθαρισμό του δείγματος. Πραγματοποιήθηκε η επικύρωση της μεθόδου σύμφωνα με τις οδηγίες της SANTE/11813/2017 με έλεγχο της γραμμικότητας, των ορίων ανίχνευσης (LODs) και ποσοτικοποίησης (LOQs), της ορθότητας μέσω του υπολογισμού των ποσοστιαίων ανακτήσεων και της πιστότητας της μεθόδου μέσω του υπολογισμού της επαναληψιμότητας (%RSDr) και της αναπαραγωγιμότητας (%RSDWR). Υπό βέλτιστες συνθήκες, τα LODs και LOQs κυμάνθηκαν σε σχετικά ικανοποιητικά επίπεδα (LOQ< 10 μg/Kg), με την επαναληψιμότητα (%RSDr) και την αναπαραγωγιμότητα (%RSDWR) της δοκιμής να είναι <20%, σχεδόν για όλες τις ενώσεις. Οι μέσες ανακτήσεις των φυτοφαρμάκων κυμάνθηκαν από 60 έως 120% για τις περισσότερες από τις μελετώμενες ενώσεις.This study reports an analytical method for the determination of residues of pesticides using liquid chromatography mass spectrometry (LC-MS). A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) methodology was used to extract the analytes and determine different groups of pesticides in soil samples by LC-MS. Optimization of the method was performed by studding parameters affecting QuEChERS in both extraction/partitioning and clean up steps. Different extraction solvents, amounts and combinations of salts as well as clean-up sorbents (C18, GCB, PSA, Florisil) were investigated and compared. Finally, the optimized method was validated by evaluating the linearity, accuracy, precision (repeatability, reproducibility), method detection and quantification limits (LODs, LOQs) according το SANTE/11813/2017 guidelines

Three years of wastewater surveillance for new psychoactive substances from 16 countries

The proliferation of new psychoactive substances (NPS) over recent years has made their surveillance complex. The analysis of raw municipal influent wastewater can allow a broader insight into community consumption patterns of NPS. This study examines data from an international wastewater surveillance program that collected and analysed influent wastewater samples from up to 47 sites in 16 countries between 2019 and 2022. Influent wastewater samples were collected over the New Year period and analysed using validated liquid chromatography - mass spectrometry methods. Over the three years, a total of 18 NPS were found in at least one site. Synthetic cathinones were the most found class followed by phenethylamines and designer benzodiazepines. Furthermore, two ketamine analogues, one plant based NPS (mitragynine) and methiopropamine were also quantified across the three years. This work demonstrates that NPS are used across different continents and countries with the use of some more evident in particular regions. For example, mitragynine has highest mass loads in sites in the United States, while eutylone and 3-methylmethcathinone increased considerably in New Zealand and in several European countries, respectively. Moreover, 2F-deschloroketamine, an analogue of ketamine, has emerged more recently and could be quantified in several sites, including one in China, where it is considered as one of the drugs of most concern. Finally, some NPS were detected in specific regions during the initial sampling campaigns and spread to additional sites by the third campaign. Hence, wastewater surveillance can provide an insight into temporal and spatial trends of NPS use

Three years of wastewater surveillance for new psychoactive substances from 16 countries

The proliferation of new psychoactive substances (NPS) over recent years has made their surveillance complex. The analysis of raw municipal influent wastewater can allow a broader insight into community consumption patterns of NPS. This study examines data from an international wastewater surveillance program that collected and analysed influent wastewater samples from up to 47 sites in 16 countries between 2019 and 2022. Influent wastewater samples were collected over the New Year period and analysed using validated liquid chromatog-raphy - mass spectrometry methods. Over the three years, a total of 18 NPS were found in at least one site. Synthetic cathinones were the most found class followed by phenethylamines and designer benzodiazepines. Furthermore, two ketamine analogues, one plant based NPS (mitragynine) and methiopropamine were also quantified across the three years. This work demonstrates that NPS are used across different continents and countries with the use of some more evident in particular regions. For example, mitragynine has highest mass loads in sites in the United States, while eutylone and 3-methylmethcathinone increased considerably in New Zealand and in several European countries, respectively. Moreover, 2F-deschloroketamine, an analogue of ke-tamine, has emerged more recently and could be quantified in several sites, including one in China, where it is considered as one of the drugs of most concern. Finally, some NPS were detected in specific regions during the initial sampling campaigns and spread to additional sites by the third campaign. Hence, wastewater surveillance can provide an insight into temporal and spatial trends of NPS use