Determination of persistent and mobile organic contaminants (PMOCs) in water by mixed-mode liquid chromatography-tandem mass spectrometry

The presence of persistent and mobile organic contaminants (PMOC) in aquatic environments has become a matter of concern due to their ability of breaking through natural and anthropogenic barriers, even reaching drinking water. The presence of many of these compounds in surface and drinking water has been reported in screening studies, but there is still a lack of analytical methods capable of quantifying them. Herein, we propose a method combining mixed-mode-solid-phase extraction (MM-SPE) as preconcentration technique and mixed-mode liquid chromatography (MMLC) coupled to tandem mass spectrometry as a determination technique for the quantitative determination of 23 target PMOCs in surface and drinking water samples. When compared to reversed-phase liquid chromatography, the MMLC protocol has proven to be superior in both retentive capabilities and peak shape for ionic compounds, while performing also well for neutrals. The overall method performance was satisfactory with limits of quantification under 50 ng L–1 for most of analytes in both surface and drinking water. The relative standard deviation was lower than 20%, and the average recovery was 78 and 80% in surface and drinking water, respectively. The method was applied to 15 water samples collected in Spain, where 17 out of the 23 target PMOCs were quantified in at least one sample. Among them, 6 chemicals (e.g., benzyltrimethylammonium) are reported and/or quantified here for the first timeThis work has been funded by the Spanish MINECO/AEI (JPIW2013-117, CTM2014-56628-C3-2-R, and CTM2017-84763-C3-2-R) in the frame of the collaborative international consortium (WATERJPI2013 – PROMOTE) of the Water Challenges for a Changing World Joint Programming Initiative (Water JPI) Pilot Call, the Galician Council of Culture, Education and Universities (ED431C2017/36) and FEDER/EDRF fundingS

Determination of 18 organophosphorus flame retardants/plasticizers in mussel samples by matrix solid-phase dispersion combined to liquid chromatography-tandem mass spectrometry

This study presents the development and validation of a new analytical method based on matrix solid-phase dispersion (MSPD), integrating sample extraction and clean-up in one single step, followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the simultaneous determination of 18 organophosphorus flame retardants and/or plasticizers (OPEs) in marine mussel (Mytilus edulis and Mytilus galloprovincialis) samples. Among these OPEs, 5 (tetraethyl 1,2-ethanediylbis(phosphonate), 6H-dibenzo[c,e] [1,2]oxaphosphinine 6-oxide, tris(2,3-dibromopropyl) phosphate, 2,2-propanediyldi-4,1-phenylene bis(phosphate) and resorcinol bis(diphenyl phosphate)) are considered here for the first time in marine samples. Different parameters affecting the MSPD (clean-up sorbent and elution solvent) were optimized to obtain a good compromise between analyte recoveries and extract clean-up. Also, particular attention was paid to tackle blank issues. The overall method was validated in terms of trueness, precision and detection and quantification limits. Percentages of recovery varied from 69% to 122% with relative standard deviations below 24%. Detection limits ranged from 0.06 to 5 ng g−1 and quantification limits from 0.19 to 17 ng g−1 dry weight. Finally, the method was applied to the analysis of 7 mussel samples collected in the coast of Galicia (Spain). 8 OPEs were detected in these samples at concentrations ranging from the LOQ to 291 ng g−1 dry weight.This work was financially supported by the Spanish Agencia Estatal de Investigación (ref. CTM2017-84763-C3-2-R), the Galician Council of Culture, Education and Universities (ref. ED431C2017/36 and Verónica Castro predoctoral contract, ref. ED481A-2017/156), cofunded by FEDER/ERDFS

Transformation products of the high-volume production chemicals 1-vinyl-2-pyrrolidinone and 2-piperazin-1-ylethanamine formed by UV photolysis

This work investigates the reaction of 1-vinyl-2-pyrrolidinone (VP) and 2-piperazin-1-yletanamine (PPE) under UV radiation. Both substances are high-volume production chemicals (production >1000 tons/year) widely used in polymers, coatings and a wide array of applications, which have been classified as mobile chemicals and which can then lead to the formation of persistent and mobile transformation products (TPs). Thus, their reaction with UV light was studied by means of liquid chromatography-quadrupole-time-of-flight-mass spectrometry (LC-QTOF-MS). Both compounds presented a high reactivity, the VP quantum yield was 0.28 mol/E; whereas, PPE had a quantum yield notably higher than 1 (16 mol/E). Five and 7 TPs were identified for VP and PPE, respectively. Some of them had been already reported in literature due to sunlight photodegradation or other oxidation processes, but most of them are reported here for the first time. Finally, the acute and chronical toxicity of precursors and TPs were estimated using two quantitative structure-activity relationship (QSAR) software tools which led to some discrepancies in the estimations, pointing to the need for experimental toxicity assays for these compoundsThis work was supported by the Water Challenges for a Changing World Joint Program Initiative (Water JPI) Pilot Call (ref. WATERJPI2013 – PROMOTE), funded by the Spanish Ministry of Economy and Competitiveness/Spanish Agencia Estatal de Investigación (refs. JPIW 2013-117, CTM2017-84763-C3-2-R and PID2020-117686RB-C32). We also acknowledge the Galician Council of Culture, Education and Universities (ref. ED431C2021/06). This research has been co-financed by the European Regional Development Fund through the Interreg V-A Spain-Portugal Programme (POCTEP) 2014–2020 (ref. 0725_NOR_WATER_1_P). It only reflects the author's view; thus, Programme authorities are not liable for any use that may be made of the information contained therein.S

Applicability of mixed-mode chromatography for the simultaneous analysis of C1-C18 perfluoroalkylated substances

This is a post-peer-review, pre-copyedit version of an article published in Analytical and Bioanalytical Chemistry. The final authenticated version is available online at: https://doi.org/10.1007/s00216-020-02434-wA new analytical method for the determination of 22 perfluoroalkylated (carboxylic and sulfonic) acids in water samples is presented. The method's objective was to achieve the simultaneous quantification of compounds with different chain lengths (from C1 to C18). To this end, 500 mL of water were extracted with Oasis WAX solid-phase extraction cartridges and eluted with 3 mL of 5% ammonia in methanol. After evaporation to dryness, extracts were reconstituted in methanol:ultrapure water (1:1) and analyzed by mixed-mode liquid chromatography-tandem mass spectrometry (MMLC-MS/MS) using a weak anion exchange/reversed-phase column. The method provided good results, with limits of quantification lower than 1 ng/L in river water for most of compounds, except the two perfluorocarboxylic acids with the longest alkyl chain (>C14) and trifluoroacetic acid, for which a blank contamination problem was observed. The method proved good trueness and precision in both ultrapure and river water (R ≥ 81%, RSD ≤ 15%). After validation, the method was applied to the analysis of nine water samples where nine perfluoroalkylated acids were quantified. Seven of them were ultrashort- (C1-C4) and short-chain (C4-C8) perfluoroalkylated acids, pointing out the importance of developing methods capable to target such substances for further monitoringThis work was supported by the Water Challenges for a Changing World Joint Program Initiative (Water JPI) Pilot Call (ref. WATERJPI2013 – PROMOTE), the Spanish Ministry of Economy and Competitiveness/Spanish Agencia Estatal de Investigación (refs. JPIW2013-117 and CTM2017-84763-C3-2-R), the Galician Council of Culture, Education and Universities (ref. ED431C2017/36) and FEDER/EDRF fundingS

Chlorination and bromination of 1,3-diphenylguanidine and 1,3-di-o-tolylguanidine: Kinetics, transformation products and toxicity assessment

This works investigates the chlorination and bromination of two rubber and polymer related chemicals, which have emerged as relevant water contaminants, i.e. 1,3-di-o-tolylguanidine (DTG) and 1,3-diphenylguanidine (DPG). Kinetic constants at different pH values were obtained and modelled, taking into account the pKa values of DTG/DPG and HClO, showing that the maximum reaction rate (kapp > 104 M−1 s−1) is obtained at pH values 8.8 for DPG and 9.1 for DTG. Bromination is also very fast, although unlike chlorination, deviation from the model was observed at neutral pH, which was attributed to formation of metastable transformation product (TP). A total of 35 TPs, corresponding to halogenation, hydroxylation, formation of monophenylguanidine derivatives and cyclization reactions, were tentatively identified. Furthermore it was found that chloroform can be formed up to a 25% molar yield, while dichloroacetonitrile was formed into less than a 3% yield. Several ecotoxicological endpoints were predicted by quantitative structure–activity relationship models (QSAR) for the TPs, some of which were predicted to be more toxic than DPG/DTG. Also a chlorinated solution investigated by a Vibrio Fisheri acute toxicity test, confirmed that toxicity increases with chlorination.This work was supported by the Water Challenges for a Changing World Joint Program Initiative (Water JPI) Pilot Call (ref. WATERJPI2013 – PROMOTE), funded by the Spanish Ministry of Economy and Competitiveness/Spanish Agencia Estatal de Investigación (refs. JPIW2013-117 and CTM2017-84763-C3-2-R) and French Office National de l’Eau et des Milieux Aquatiques (ref. PROMOTE). We also acknowledge the Galician Council of Culture, Education and Universities (ref. ED431C2017/36), Région Nouvelle Aquitaine and FEDER/EDRF funding. Benigno J. Sieira acknwledges the COST (European Cooperation in Science and Technology) Action ES1307 for suporting his research stay in PoitiersS

Occurrence of emerging persistent and mobile organic contaminants in European water samples

This is the Author’s Accepted Manuscript of the following article: Schulze, S., Zahn, D., Montes, R., Rodil, R., Quintana, J., & Knepper, T. et al. (2019). Occurrence of emerging persistent and mobile organic contaminants in European water samples. Water Research, 153, 80-90. doi: 10.1016/j.watres.2019.01.008The release of persistent and mobile organic chemicals (PMOCs) into the aquatic environment puts the quality of water resources at risk. PMOCs are challenging to analyze in water samples, due to their high polarity. The aim of this study was to develop novel analytical methods for PMOCs and to investigate their occurrence in surface and groundwater samples. The target compounds were culled from a prioritized list of industrial chemicals that were modeled to be persistent, mobile, and emitted into the environment. Analytical screening methods based on mixed-mode liquid chromatography (LC), hydrophilic interaction LC, reversed phase LC, or supercritical fluid chromatography in combination with mass spectrometric detection were successfully developed for 57 target PMOCs and applied to 14 water samples from three European countries. A total of 43 PMOCs were detected in at least one sample, among them 23 PMOCs that have not been reported before to occur in environmental waters. The most prevalent of these novel PMOCs were methyl sulfate, 2-acrylamino-2-methylpropane sulfonate, benzyltrimethylammonium, benzyldimethylamine, trifluoromethanesulfonic acid, 6-methyl-1,3,5-triazine-diamine, and 1,3-di-o-tolylguanidine occurring in ≥50% of the samples at estimated concentrations in the low ng L−1 up to μg L−1 range. The approach of focused prioritization combined with sensitive target chemical analysis proved to be highly efficient in revealing a large suite of novel as well as scarcely investigated PMOCs in surface and groundwaterThis work has been funded by the German BMBF (02WU1347A/B) and the Spanish MINECO/AEI (JPIW2013-117) in the frame of the collaborative international consortium (WATERJPI2013 – PROMOTE) of the Water Challenges for a Changing World Joint Programming Initiative (Water JPI) Pilot Call. RM, RR and JBQ also acknowledge Galician Council of Culture, Education and Universities and FEDER/EDRF funding (ED431C2017/36)S

Multi-residue determination of psychoactive pharmaceuticals, illicit drugs and related metabolites in wastewater by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

This is the Author’s Accepted Manuscript of the following article: González-Mariño, I., Castro, V., Montes, R., Rodil, R., Lores, A., Cela, R., & Quintana, J. (2018). Multi-residue determination of psychoactive pharmaceuticals, illicit drugs and related metabolites in wastewater by ultra-high performance liquid chromatography-tandem mass spectrometry. Journal Of Chromatography A, 1569, 91-100. doi: 10.1016/j.chroma.2018.07.045 © Elsevier 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 licenseThis study presents a new multi-residue analytical method for the simultaneous determination of 38 psychoactive drugs (including benzodiazepines, antidepressants and drugs of abuse) and related metabolites in raw wastewater. Potential analyte losses during sample filtration and stability in wastewater were evaluated. Analyte losses, especially for 12 compounds, were observed during filtration, indicating a strong sorption onto the filter material. In order to overcome this effect, filtered water samples were combined with methanolic washes of the corresponding filters and the resulting solutions were solid-phase extracted on mixed-mode (reverse-phase plus cation-exchange) sorbents. Extracts were analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry. Quantification was performed by the internal standard method with isotopic labeled analogs. Recovery percentages varied between 65% and 137%; method quantification limits ranged between 0.2 and 22 ng/L in ultrapure water and between 0.3 and 30 ng/L in wastewater for all the analytes but three (for which they were ∼60–80 ng/L). The analysis of 24 h-composite samples collected during one week in the city of Santiago de Compostela demonstrated the ubiquity of 31 analytes, which were positively quantified in all samples. The highest concentrations were found for some of the antidepressants, with mean and maximum levels exceeding, in some cases, the levels previously reported in literature. This fact could be related to the additional washing step of the filters using methanol, which allowed to desorb retained analytes highlighting the importance of this step during the sample preparation protocolS

Chronic environmentally relevant levels of simvastatin disrupt embryonic development, biochemical and molecular responses in zebrafish (Danio rerio)

This is the postprint (accepted manuscript) version of the article published in Aquatic Toxicology. https://doi.org/10.1016/j.aquatox.2018.05.014Simvastatin (SIM), a hypocholesterolaemic compound, is among the most prescribed pharmaceuticals for cardiovascular disease prevention worldwide. Several studies have shown that acute exposure to SIM causes multiple adverse effects in aquatic organisms. However, uncertainties still remain regarding the chronic effects of SIM in aquatic ecosystems. Therefore, the present study aimed to investigate the effects of SIM in the model freshwater teleost zebrafish (Danio rerio) following a chronic exposure (90 days) to environmentally relevant concentrations ranging from 8 ng/L to 1000 ng/L. This study used a multi-parameter approach integrating distinct ecologically-relevant endpoints, i.e. survival, growth, reproduction and embryonic development, with biochemical markers (cholesterol and triglycerides). Real Time PCR was used to analyse the transcription levels of key genes involved in the mevalonate pathway (hmgcra, cyp51, and dhcr7). Globally, SIM induced several effects that did not follow a dose-response relationship; embryonic development, biochemical and molecular markers, were significantly impacted in the lower concentrations, 8 ng/L, 40 ng/L and/or 200 ng/L, whereas no effects were recorded for the highest tested SIM levels (1000 ng/L). Taken together, these findings expand our understanding of statin effects in teleosts, demonstrating significant impacts at environmentally relevant concentrations and highlight the importance of addressing the effects of chemicals under chronic low-level concentrationsT. Neuparth was supported by the Postdoctoral fellowship SFRH/BPD/77912/2011 from Foundation of Science and Technology, Portugal. R. Montes, R. Rodil and J.B. Quintana acknowledge financial support from the Spanish “Agencia Estatal de Investigación” (project no. CTM2014-56628-C3-2-R), the Galician Council of Culture, Education and Universities (ED431C2017/36) and FEDER/ERDFS

2,3-Diarylxanthones as potential inhibitors of Arachidonic acid metabolic pathways

In response to an inflammatory stimulus, arachidonic acid (AA), the main polyunsaturated fatty acid present in the phospholipid layer of cell membranes, is released and metabolized to a series of eicosanoids. These bioactive lipid mediators of inflammation arise physiologically through the action of the enzymes 5-lipoxygenase (5-LOX) and cyclooxygenases (constitutive COX-1 and inducible COX-2). It is believed that dual inhibition of 5-LOX and COXs may have a higher beneficial impact in the treatment of inflammatory disorders rather than the inhibition of each enzyme. With this demand for new dual-acting anti-inflammatory agents, a range of 2,3-diarylxanthones were tested through their ability to interact in the AA metabolism. In vitro anti-inflammatory activity was evaluated through the inhibition of 5-LOX-catalyzed leukotriene B4 (LTB4) formation in human neutrophils and inhibition of COX-1- and COX-2-catalyzed prostaglandin E2 (PGE2) formation in human whole blood. The results showed that some of the studied arylxanthones were able to prevent LTB4 production in human neutrophils, in a concentration-dependent manner. The xanthone with a 2-catechol was the most active one (IC50 ∼ 9 μM). The more effective arylxanthones in preventing COX-1-catalyzed PGE2 production presented IC50 values from 1 to 7 μM, exhibiting a structural feature with at least one non-substituted aryl group. All the studied arylxanthones were ineffective to prevent the formation of PGE2 catalyzed by COX-2, up to the maximum concentration of 100 μM. The ability of the tested 2,3-diarylxanthones to interact with both 5-LOX and COX-1 pathways constitutes an important step in the research of novel dual-acting anti-inflammatory drugs.Sincere thanks are expressed to Faculdade de Farmácia da Universidade do Porto, Universidade de Aveiro, Instituto Politécnico de Bragança, Fundação para a Ciência e a Tecnologia (FCT, Portugal), Ministério da Educação e Ciência, European Union, FEDER, PT 2020, QREN, and COMPETE funding UCIBIO, REQUIMTE [(PT2020 UID/MULTI/04378/2013 - POCI/01/0145/FEDER/007728), (NORTE-01-0145-FEDER-000024), and (PTDC/QEQ-QAN/1742/2014 – POCI-01-0145- FEDER-016530)] and QOPNA (FCT UID/QUI/00062/2013) Research Units and also to the Portuguese National NMR Network (RNRMN). We gratefully acknowledge Graça Porto and the nursing staff of the Centro Hospitalar do Porto - Hospital de Santo António blood bank for the collaboration in the recruitment of blood donors involved in the present work.info:eu-repo/semantics/publishedVersio

Ozone membrane contactor to intensify gas/liquid mass transfer and contaminants of emerging concern oxidation

A tubular porous borosilicate membrane contactor was investigated for ozone gas/water mass transfer and the removal of contaminants of emerging concern (CECs) in water. Ozone gas/water contact occurs on the membrane shell-side, which is coated with a photocatalyst (TiO2-P25), as the ozone gas stream is fed from the lumen side and permeates through the pores generating micro-sized ozone bubbles uniformly delivered to the annular reaction zone where the contaminated water to be treated flows. Under continuous flow, water pH at 3.0 and temperature at 20 ºC, the volumetric mass transfer coefficient (KLa) ranged from 3.5 to 9.0 min−1 and improved with the increase of gas flow rate (QG, 1.5-fold from 0.15 to 1.0 Ndm3 min−1) and liquid flow rate (QL, 2.0-fold from 20 to 50 L h−1), due to enhanced turbulence on the membrane shell-side and annular zone. The mass transfer efficiency was more pronounced as the QG decreased and the QL increased, which is advantageous for large-scale applications. The main resistances to ozone transfer were in the water phase boundary layer (53–76%) and in the membrane (24–47%; kM = (1.14 ± 0.01) × 10−4 m s−1). For an ozone dose of 12 g m−3 and residence time of 3.9 s, removals ≥ 80% were achieved for 13 of 19 CECs spiked in demineralized water (each 10 µg L−1), demonstrating the applicability of this membrane contactor for ozonation treatment. Photocatalytic ozonation (O3/UVC/TiO2) did not significantly improve the treatment performance due to the low residence time inside the contactor.This work was financially supported by (i) Project NOR-WATER funded by INTERREG VA Spain-Portugal cooperation programme, Cross-Border North Portugal/Galizia Spain Cooperation Program (POCTEP), ref. 0725_NOR_WATER_1_P; (ii) National funds through the FCT/MCTES (PIDDAC), under the project PTDC/EAM-AMB/4702/2020 (OZONE4WATER); (iii) Project “Healthy Waters – Identification, Elimination, Social Awareness and Education of Water Chemical and Biological Micropollutants with Health and Environmental Implications”, with reference NORTE-01-0145-FEDER-000069, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); and (iv) LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), and also UIDB/00511/2020 and UIDP/00511/2020 (LEPABE), funded by national funds through FCT/MCTES (PIDDAC). P. H. Presumido acknowledges FCT for his scholarship (SFRH/BD/138756/2018). Vítor J.P. Vilar acknowledges the FCT Individual Call to Scientific Employment Stimulus 2017 (CEECIND/01317/2017). The researchers from the University of Santiago de Compostela would also like to acknowledge funding provided by Xunta de Galicia (ED431C 2021/06), the Spanish Agencia Estatal de Investigación –MCIN/AEI/10.13039/501100011033 (ref. PID2020-117686RB-C32) and Banco Santander and Universidade de Santiago de Compostela for the sponsorship of “outstanding researcher contract” of R. Montes.S