Validation of analytical method for determination of triazines in aquaculture trout

[Resumo] Neste traballo, validouse un método baseado na dispersión da matriz en fase sólida (MSPD) para a extracción de nove triazinas en mostras de troita. Nas condicións optimizadas, 0.2 g de mostra dispersáronse sobre 2 g de C18 e transferíronse a un cartucho con ENVI-Carb-II/SAX/PSA (500/500/500 mg). A mostra dispersada lavouse con 10 mL de n-hexano e os analitos eluíronse con 20 mL de acetato de etilo e 5 mL de acetonitrilo. O extracto concentrouse ata sequedade, redisolveuse en 1 mL de metanol e inxectouse en HPLC-DAD. O método proporcionou unha boa exactidude e precisión, cumprindo así cos requisitos estipulados na lexislación da Unión Europea.[Resumen] En este trabajo, se validó un método de dispersión de la matriz en fase sólida (MSPD) para la extracción de nueve triazinas en muestras de trucha. En las condiciones optimizadas, 0.2 g de muestra se dispersaron sobre 2 g de C18 y se transfirieron a un cartucho con ENVI-Carb-II/SAX/PSA (500/500/500 mg). La muestra dispersada se lavó con 10 mL de n-hexano y los analitos se eluyeron con 20 mL de acetato de etilo y 5 ml de acetonitrilo. El extracto se concentró hasta sequedad, se redisolvió en 1 mL de metanol y se inyectó en HPLC-DAD. El método proporcionó una buena exactitud y precisión, cumpliendo así con los requisitos estipulados en la legislación de la Unión Europea.[Abstract] In this project, Matrix Solid Phase Dispersion (MSPD) has been validated for extraction of nine triazine in trout samples. Under optimised conditions, 0.2 g sample were dispersed using 2 g of C18, and transferred to a cartridge containing ENVI-Carb-II/SAX/PSA (500/500/500 mg). The dispersed sample was washed with 10 mL of n-hexane and analytes were eluted with 20 mL ethyl acetate and 5 mL acetonitrile. The extract was concentrated to dryness, re-constituted with 1 mL methanol and injected into the HPLC-DAD system. The method provided satisfactory accuracy and precision, meeting the requirements stipulated by European Union legislation.Traballo fin de grao (UDC.CIE). Química. Curso 2014/201

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

Determination of human metabolites of chlorinated phosphorous flame retardants in wastewater by N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide-derivatization and gas chromatography-high resolution mass spectrometry

The analysis of wastewater for the determination of human biomarkers of exposure (human metabolites) is a non-intrusive, economic and complementary alternative to the analysis of urine in the monitoring of human exposure to chemicals of concern. This study provides the first gas chromatography-based method for the determination of three metabolites of chlorinated organophosphorous flame retardants (OPFRs: bis(2-chloroethyl) phosphate, bis(chloropropyl) phosphate and bis(1,3-dichloro-2-propyl) phosphate) in wastewater. A solid-phase extraction procedure based on the use of mixed-mode reversed-phase weak anion exchange sorbents was optimized including a fractionated elution of OPFRs and their metabolites. Analytes derivatization was investigated by comparing two silylating reagents, N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide and N-methyl-N-(trimethylsilyl)trifluoroacetamide, the first one providing better results. Determination was performed by gas chromatography-high resolution mass spectrometry with a quadrupole-time-of-flight system (GC-QTOF) in order to improve selectivity. Furthermore, the use of GC-QTOF combined with the specific ion obtained from silylated metabolites (m/z 154.9924) can be exploited to screen for other phosphate ester metabolites. Under final conditions, the overall method performance was satisfactory, affording method detection limits ranging from 1.1 to 4.6 ng/L, percentages of recovery from 90% to 110%, and relative standard deviations below 13%. The analysis of composite raw wastewater samples collected over 24 h in the NW of Spain allowed to quantify, for the first time in this matrix, the metabolite bis(chloropropyl) phosphate at levels over 60 ng/LThis work was financially supported by the Spanish Agencia Estatal de Investigación (project no. CTM2017-84763-C3-2-R), the Galician Council of Culture, Education and Universities (ED431C2017/36, VC predoctoral contract, ED481A-2017/156, and IGM postdoctoral contract, Plan Galego I2C-Modalidade B, ED481D 2017/003), Gil Dávila Foundation (VC research grant) and FEDER/ERDFS

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

Using zebrafish embryo bioassays combined with high-resolution mass spectrometry screening to assess ecotoxicological water bodies quality status: A case study in Panama rivers

Several studies show that many water bodies in developing countries are increasingly affected by anthropogenic pressure, such as agricultural activities, domestic and industrial wastewater. However, data is scarce in several of such countries, including Panama. Thus, in this work, the ecotoxicological status of selected rivers in Panama with distinct input sources were evaluated using the zebrafish (Danio rerio) embryo bioassays combined with a liquid chromatography-high resolution mass spectrometry screening of contaminants of emerging concern (CECs), using a library of over 3200 chemicals. A total of 68 CECs, including pharmaceuticals and metabolites, pesticides and several industrial chemicals, could be tentatively identified. Additionally, the zebrafish embryo bioassays showed a significant increase (p < 0.05) in embryo mortality/abnormalities when incubated with water samples from two rivers, Matasnillo and Curundú (47.5% and 32%, respectively). Importantly, a positive correlation between ecotoxicological endpoints and some of the detected CECs was observed. The findings demonstrate that both rivers are under strong anthropogenic pressure, and therefore, management actions are urgently needed to decrease their level of contamination. Overall, this study further supports the use of the zebrafish embryo bioassay as a fast, high throughput approach for screening the toxicity of water samples, and highlights the advantages of combining ecotoxicological assays with high-resolution mass spectrometry to an expedite assessment of the ecotoxicological status of water bodies.This work was supported by the Portuguese Foundation for Science and Technology (FCT) (PTDC|CTA-AMB|31554|2017; UIDB/04423/2020; UIDP/04423/2020), 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), co-funded by the European Regional Development Fund (ERDF/FEDER).2023-02-02S

Tracking pollutants in a municipal sewage network impairing the operation of a wastewater treatment plant

This work provides a screening of organic contaminants and characterization of the dissolved organic matter in the sewer network until the municipal wastewater treatment plant (WWTP), identifying the network areas with a higher degree of contamination and their impact on the WWTP performance, particularly in the activated sludge reactor. Three monitoring campaigns were carried out at six selected locations of the sewage system (PVZ-1, PVZ-2, PS-F, PS-VC, CP-VC, and PS-T), influent (WWTPINF) and effluent (WWTPEFF) of the WWTP. Advanced analytical techniques were employed, namely excitation/emission matrix fluorescence-parallel factor analysis (EEM-PARAFAC), size exclusion chromatography with organic carbon detector (SEC-OCD), and liquid chromatography with high-resolution-mass spectrometric detection (LC-HRMS). EEM-PARAFAC showed higher fluorescence intensity for the protein-like component (C2), particularly at CP-VC (near seafood industries) associated with the presence of surfactants (~50 mg/L). SEC-OCD highlighted the WWTP efficiency in removing low molecular weight acids and neutrals. LC-HRMS tentatively identified 108 compounds of emerging concern (CEC) and similar detection patterns were obtained for all wastewater samples, except for PVZ-2 (lower detection), many of which occurred in the effluent. Eight CECs included on relevant Watch-Lists were detected in all WWTPEFF samples. Furthermore, 111 surfactants were detected, the classes more frequently found being alcohol ethoxylates (AEOs), nonylphenol polyethoxylates (NPEOs) and linear alkylbenzene sulphonates (LAS). The continuous presence of LAS and NPEOs allied to surfactants concentrations in the WWTPINF of 15–20 mg/L, with CP-VC location (linked with food industries) as an important contributor, explain the morphological changes in the activated sludge and high LAS content in the dewatered sludge, which may have impacted WWTP performance.i) Base-UIDB/50020/2020 and Programmatic-UIDP/50020/2020 Funding of LSRE-LCM, funded by national funds through FCT/MCTES (PIDDAC); ii) European Regional Development Fund through the Interreg V-A Spain-Portugal Programme (POCTEP) 2014–2020 (ref. 0725_NOR_WATER_1_P); iii) Xunta de Galicia (Verónica Castro predoctoral contract: ED481A-2017/156, and ED431C2017/36), the Spanish Agencia Estatal de Investigación – MCIN/AEI/ 10.13039/501100011033 (ref. PID2020-117686RB-C32); iv) NORTE-01-0145-FEDER-000069 (Healthy Waters) co-funded by European Regional Development Fund (ERDF), through North Portugal Regional Operational Programme (NORTE2020), under the PORTUGAL 2020 Partnership Agreement. The authors also acknowledge Águas do Norte, S.A. for supporting the development of this work. Daniela F.S. Morais acknowledges her Ph.D. scholarship supported by FCT (SFRH/BD/146476/2019). Bianca M. Souza Chaves gratefully acknowledges her postdoctoral scholarship supported by CNPq through the Science Without Borders Program (Process No. 201989/2014-0). Vítor J.P. Vilar acknowledges the FCT Individual Call to Scientific Employment Stimulus 2017 (CEECIND/01317/2017)S

Screening and Quantitative Analysis of Contaminants of Emerging Concern by Chomatographic Techniques Coupled to Low and High-Resolution Mass Spectrometry

This thesis is primarily focused on developing LC-HRMS, GC-HRMS and SFC-HRMS screening methods, which are subsequently applied to different environmental samples of Galicia (Spain), Portugal and Panamá. As a second step, organophosphate flame retardants and plasticizers (OPFRs), which were frequently detected in many samples during the screening studies were targeted by developing methods and exploring their fate (bioaccumulation by mussels) in the marine environment (because of its relevance for the Galician economy). Finally, human exposure to chlorinated organophosphate esters (OPEs) and consumption of licit and illicit drugs, also frequently detected during screening, was explored by applying the wastewater-based epidemiology (WBE) methodology

Bioaccumulation of organophosphorus flame retardants in the marine mussel Mytilus galloprovincialis

The bioaccumulation and depuration of seven organophosphorus flame retardants (OPFRs) in marine mussel Mytilus galloprovincialis were studied. OPFRs showed to be bioavailable in aquatic environments. When mussels are exposed to environmentally relevant concentrations of OPFRs, uptake kinetics fit well to a first-order model with a single compartment; in contrast depuration rates were generally underestimated by that model, most likely because it does not take into account the biotransformation of OPFRs by the organisms. The highest bioaccumulation rates were observed for tricresyl phosphate (TCrP), triphenyl phosphate (TPhP) and 2-ethylhexyldiphenylphosphate (EHDPP). This could be due to the presence of aryl groups in these compounds, their low solubility in water, and their affinity for fat tissues. According to these findings TCrP, with a BCF value of 4042 L kg−1 wet weight, should be classified in environmental regulations as an accumulative chemicalThis research was supported by the Spanish Government through research project BIOPLAS (PID2019-108857RB-C32), the Spanish Agencia Estatal de Investigación (ref. CTM2017-84763-C3-R-2), Xunta de Galicia (ED431C2017/36 and Verónica Castro predoctoral contract, ref.: ED481A-2017/156) and FEDER/ERDF funds. This work has received financial support from the Xunta de Galicia (Centro de investigación de Galicia accreditation 2019-2022) and the European Union (European Regional Development Fund - ERDF)2023-09-17S

Combination of different chromatographic and sampling modes for high-resolution mass spectrometric screening of organic microcontaminants in water

This study explores the combination of two sampling strategies (polar organic compounds integrative sampler (POCIS) vs. spot sampling) and four chromatographic retention modes (reversed-phase liquid chromatography (RPLC), hydrophilic interaction liquid chromatography (HILIC), mixed-mode liquid chromatography (MMLC) and supercritical fluid chromatography (SFC)) for high-resolution mass spectrometry (HRMS) screening of organic pollutants in water samples. To this end, a suspect screening approach, using iterative data-dependent tandem mass spectrometry (MS/MS) driven by a library of 3227 chemicals (including pharmaceuticals, pesticides, drugs of abuse, human metabolites, industrial chemicals and other pollutants), was employed. Results show that POCIS can afford a larger number of positive identifications as compared to spot sampling. On the other hand, the best suited retention mechanisms, in terms of identified analytes, are SFC, and followed by RPLC, MMLC and HILIC. However, the best combination (POCIS + SFC) would only allow the identification of 67% of the detected analytes. Thus, the combination of the two sampling strategies, spot and passive sampling, with two orthogonal retention mechanisms, RPLC and SFC, is proposed in order to maximize the number of analytes detected (89%). This strategy was applied to different surface water (river and estuary) samples from Galicia (NW Spain). A total of 155 compounds were detected at a confidence level 2a, from which the major class was pharmaceuticals (61%).This research was funded by Xunta de Galicia (ED431C2017/36 and V.C. predoctoral contract: ED481A-2017/156), the Spanish Agencia Estatal de Investigación (ref. CTM2017-84763-C3-R-2 and CTM2017-90980-REDT) and FEDER/ERDF funds. 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

Development and application of an in-house library and workflow for gas chromatography–electron ionization–accurate-mass/high-resolution mass spectrometry screening of environmental samples

This work presents an optimized gas chromatography–electron ionization–high-resolution mass spectrometry (GC-EI-HRMS) screening method. Different method parameters affecting data processing with the Agilent Unknowns Analysis SureMass deconvolution software were optimized in order to achieve the best compromise between false positives and false negatives. To this end, an accurate-mass library of 26 model compounds was created. Then, five replicates of mussel extracts were spiked with a mixture of these 26 compounds at two concentration levels (10 and 100 ng/g dry weight in mussel, 50 and 500 ng/mL in extract) and injected in the GC-EI-HRMS system. The results of these experiments showed that accurate mass tolerance and pure weight factor (combination of reverse-forward library search) are the most critical factors. The validation of the developed method afforded screening detection limits in the 2.5–5 ng range for passive sampler extracts and 1–2 ng/g for mussel sample extracts, and limits of quantification in the 0.6–3.2 ng and 0.1–1.8 ng/g range, for the same type of samples, respectively, for 17 model analytes. Once the method was optimized, an accurate-mass HRMS library, containing retention indexes, with ca. 355 spectra of derivatized and non-derivatized compounds was generated. This library (freely available at https://doi.org/10.5281/zenodo.5647960), together with a modified Agilent Pesticides Library of over 800 compounds, was applied to the screening of passive samplers, both of polydimethylsiloxane and polar chemical integrative samplers (POCIS), and mussel samples collected in Galicia (NW Spain), where a total of 75 chemicals could be identifiedOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was funded by Xunta de Galicia (ED431C 2021/06 and V.C. predoctoral contract: ED481A-2017/156), the Spanish Agencia Estatal de Investigación—MCIN/AEI/10.13039/501100011033 (ref. CTM2017-84763-C3-R-2 and PID2020-117686RB-C32), and FEDER/ERDF fundsS