Study of the photoinduced transformations of maprotiline in river water using liquid chromatography high-resolution mass spectrometry

Nuno Goncalves (1) , Zsuzsanna Varga (2) , Stéphane Bouchonnet (2) , Valeria Dulio (3) , Nikiforos Alygizakis (4) , Federica Dal Bello (1) , Claudio Medana (1) , Paola Calza (1)

1 UNITO - Università degli studi di Torino = University of Turin
2 LCM - Laboratoire de chimie moléculaire
3 INERIS - Institut National de l'Environnement Industriel et des Risques
4 NKUA - National and Kapodistrian University of Athens

Maprotiline was identified as a compound of potential interest further to a suspect screening test carried out for a list of more than 40,000 substances based on specific occurrence, hazard and risk indicators. Despite the high frequency of appearance of this drug in wastewater treatment stations, his environmental fate is still unknown. Herein, we investigated for the first time the maprotiline degradation pathways in river water spiked with the drug at a concentration close to those detected in natural waters. Preliminary photocatalytic experiments in ultrapure water produced 32 transformation products (TPs) resulted mainly from the multiple hydroxylation/oxidation in different positions of the drug molecule. From the river water experiments, 12 TPs were formed by photolysis matching with those observed in ultrapure water experiments, and 2 were also formed resulted from biotic degradation. Employing HPLC-HRMS, we were able to elucidate the chemical structures of TPs and assess the overall degradation mechanism. Preliminary bioassays suggested lower toxicity of TPs relatively to the parent compound.

Mots clés: CONTAMINANTS OF EMERGING CONCERN; MAPROTILINE; STRUCTURAL ELUCIDATION; DEGRADATION PATHWAY; ENVIRONMENTAL FATE; HRMS

Domaines: Autre; Sciences de l'environnement

Nuno Goncalves, Zsuzsanna Varga, Stéphane Bouchonnet, Valeria Dulio, Nikiforos Alygizakis, et al.. Study of the photoinduced transformations of maprotiline in river water using liquid chromatography high-resolution mass spectrometry. Science of the Total Environment, 2020, 755 (Part 2), pp.143556. ⟨10.1016/j.scitotenv.2020.143556⟩. ⟨ineris-03318335⟩