Post-acquisition data processing for the screening of transformation products of different organic contaminants. Two-year monitoring of river water using LC-ESI-QTOF-MS and GCxGC-EI-TOF-MS

Abstract

This study describes a comprehensive strategy for detecting and elucidating the chemical structures of expected and unexpected transformation products (TPs) from chemicals found in river water and effluent wastewater samples, using liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight mass spectrometer (LC-ESI-QTOF-MS), with post-acquisition data processing and an automated search using an in-house database. The efficacy of the mass defect filtering (MDF) approach to screen metabolites from common biotransformation pathways was tested, and it was shown to be sufficiently sensitive and applicable for detecting metabolites in environmental samples. Four omeprazole metabolites and two venlafaxine metabolites were identified in river water samples. This paper reports the analytical results obtained during 2 years of monitoring, carried out at eight sampling points along the Henares River (Spain). Multiresidue monitoring, for targeted analysis, includes a group of 122 chemicals, amongst which are pharmaceuticals, personal care products, pesticides and PAHs. For this purpose, two analytical methods were used based on direct injection with a LC-ESI-QTOF-MS system and stir bar sorptive extraction (SBSE) with bi-dimensional gas chromatography coupled with a time-of-flight spectrometer (GCxGC-EI-TOF-MS).

Analysis, occurrence, fate and risks of proton pump inhibitors, their metabolites and transformation products in aquatic environment: A review

“…Besides LVI, direct injection without preconcentration or purification process has been also performed for determination of omeprazole and pantoprazole or their TPs, based on the high sensitivity of the analytical technique used (LC-MS/MS). In the study of López et al (2014), direct injection of the samples in the chromatograph, after the appropriate filtration, took place in order to determine omeprazole TPs in river water and effluent wastewaters in Spain. Direct injection is cited also by Barreiro et al (2011) for the determination of lansoprazole and pantoprazole isomers in wastewaters in Brazil and by Luque-Espinar et al (2015) for the determination of pantoprazole in surface water and drinking water in Spain.…”

“…Meanwhile, the use of HR-MS (Q-TOF and hybrid linear ion trap (LTQ) FT Orbitrap mass spectrometer) is steadily increased in recent years and have been also successfully performed either for structure elucidation or/and screening and quantification of PPIs and their TPs in aqueous environmental samples (Boix et al, 2013(Boix et al, , 2014Boleda et al, 2013;Gómez et al, 2007;Gracia-Lor et al, 2014;Hernández et al, 2011;Ibáñez et al, 2009Ibáñez et al, , 2016Kosma et al, 2014aKosma et al, , 2014bLópez et al, 2014;Martínez Bueno et al, 2007;Petrovic et al, 2006;Ibáñez et al, 2016). More specifically, in a very interesting study, LC coupled to HR LTQ Orbitrap MS was performed for the identification of omeprazole and 23 metabolites of omeprazole in Italian municipal influent wastewater .…”

“…In other recent works López et al, 2014) a non-target analysis for the identification of omeprazole metabolites in waters by means of LC-QTOF-MS was reported. Hernández et al (2011), reported the occurrence of 1 omeprazole metabolite (4-hydroxy omeprazole sulfide or 4-desmethoxy omeprazole) in 54% of the effluent wastewaters in Spain, while López et al (2014), reported the occurrence of four metabolites in river samples in Spain.…”

“…Although, PPIs are not regularly detected, considering their high use (Godman et al, 2009(Godman et al, , 2011Woldegiorgis et al, 2009) its analytical monitoring becomes relevant. In addition, in view of the recent reports dealing with the detection of many metabolites and environmental Transformation Products (TPs) in aqueous samples (Boix et al, 2013(Boix et al, , 2014Boleda et al, 2013;Hernández et al, 2011;Gracia-Lor et al, 2014;Ibáñez et al, 2016;López et al, 2014;Ibáñez et al, 2016), environmental contamination by PPIs should be checked and evaluated more thoroughly.…”

A strategic screening approach to identify transformation products of organic micropollutants formed in natural waters

“…16,25,26 Strategies have also been developed to assist and simplify the detection of TPs directly in natural waters and wastewater, based on the use of characteristic fragmentation 27,28 or mass defect ltering. 29 Such applications mostly contribute with information on the occurrence of TPs 18,25 likely formed under the conditions during conventional wastewater treatment processes and emitted directly from the WWTPs. 7 However, there is less information available on TPs that are formed in natural waters aer discharge of their PCs.…”