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1.
Toxics ; 11(8)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37624218

RESUMEN

Aquatic environments are the final receptors of human emissions and are therefore contaminated by molecules, such as pharmaceuticals. After use, these compounds and their metabolites are discharged to wastewater treatment plants (WWTPs). During wastewater treatment, compounds may be eliminated or degraded into transformation products (TPs) or may be persistent. The aim of this study was to develop an analytical method based on high resolution mass spectrometry (HRMS) for the identification of six psychotropic drugs that are widely consumed in France and present in WWTPs, as well as their potential associated metabolites and TPs. Four out of six psychotropic drugs and between twenty-five and thirty-seven potential TPs were detected in wastewater, although this was based on full scan data. TPs not reported in the literature and specific to the study sites and therefore to the wastewater treatment processes were tentatively identified. For the selected drugs, most known and present TPs were identified, such as desmethylvenlafaxine or norcitalopram. Moreover, the short fragmentation study led rather to the identification of several TPs of carbamazepine as ubiquitous persistent TPs.

2.
Chemosphere ; 223: 232-239, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30784730

RESUMEN

Chlorinated paraffins (CPs) are high-volume chemicals used in numerous industrial applications. Their quantitative analysis is extremely challenging and this work presents the optimization of an analytical method based on gas chromatography hyphenated with electron capture negative ionization time-of-flight high-resolution mass spectrometry (GC-ECNI-TOF HRMS) for the simultaneous determination of short-chain and medium-chain CPs (SCCPs and MCCPs, respectively) in fish tissues (i.e. dorsal muscle). The resolution of the TOF-MS analyzer reduced or eliminated isobaric interferences and the CP response was optimized through Design of Experiment. A simple clean-up procedure based on adsorption chromatography further removed some potentially interfering organochlorines. Good selectivity, linearity and accuracy were achieved; method detection limits or limits of reporting were compatible with expected levels in wild fish (0.03-0.35 ng g-1 wet weight, ww, depending on the congener). This method was proven suitable for the analysis of CPs in tissues of common barbel Barbus, a fish species frequently used for water quality monitoring purposes in Europe. SCCPs and MCCPs were found to be widespread within the Rhône river basin (France). At all locations, MCCP concentrations (1.3-72.7 ng g-1 ww) were higher than those of SCCPs (0.3-10.6 ng g-1 ww) and levels were systematically lower than the proposed Predicted No Effect Concentrations (PNECs). Spatial variations of SCCP composition profiles largely surpassed those of MCCPs, suggesting the influence of local sources.


Asunto(s)
Monitoreo del Ambiente/métodos , Peces/metabolismo , Cromatografía de Gases y Espectrometría de Masas/métodos , Hidrocarburos Clorados/química , Parafina/química , Animales , Francia , Hidrocarburos Clorados/análisis , Límite de Detección , Modelos de Interacción Espacial , Parafina/análisis , Ríos/química
3.
Environ Sci Pollut Res Int ; 25(24): 23574-23582, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27834049

RESUMEN

This study addresses the spatio-temporal dynamics of per and polyfluoroalkyl substances (PFASs) in a highly urbanized freshwater hydrosystem, the Seine River (NW France). The distribution of PFASs between water, sediment, and periphytic biofilm was investigated at three sampling sites along a longitudinal gradient upstream and downstream from the Paris urban area. Seasonal variability was assessed through four sampling campaigns performed under contrasting hydrological conditions. In the dissolved phase, ∑PFASs fluctuated between 2 and 9 ng L-1 upstream and 6-105 ng L-1 downstream from Paris. Negative correlations between dissolved PFAS levels and river flow rate were generally observed, corroborating the predominance of point-source PFAS inputs at these sites. 18/19 target PFASs were detected, with a predominance of PFHxS and PFOS (20% of ∑PFASs each), except for the farthest downstream site where 6:2 FTSA was prevalent (35 ± 8% of ∑PFASs), likely reflecting industrial and urban inputs. In biofilms, ∑PFASs fell in the 4-32 ng g-1 dw range, and substantial bioconcentration factors (BCFs) were reported for PFNA, PFDA, and PFOS (log BCF 2.1-4.3), higher than those of PFHxS or PFOA. BCFs varied inversely with dissolved PFAS levels, potentially pointing to concentration-dependent bioaccumulation. Biofilm community characteristics (C/N ratio) may also be an influential determinant of PFAS bioaccumulation. Graphical abstract ᅟ.


Asunto(s)
Fluorocarburos/análisis , Perifiton , Ríos/química , Contaminantes Químicos del Agua/análisis , Biopelículas , Monitoreo del Ambiente , Fluorocarburos/química , Francia , Sedimentos Geológicos/análisis , Paris , Estaciones del Año , Análisis Espacio-Temporal
4.
Chemosphere ; 193: 329-336, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29149708

RESUMEN

Kinetics of photodegradation of novel oral anticoagulants dabigatran, rivaroxaban, and apixaban were studied under simulated solar light irradiation in purified, mineral, and river waters. Dabigatran and rivaroxaban underwent direct photolysis with polychromatic quantum yields of 2.2 × 10-4 and 4.4 × 10-2, respectively. The direct photodegradation of apixaban was not observed after 19 h of irradiation. Kinetics of degradation of rivaroxaban was not impacted by the nature of the aqueous matrix while photosensitization from nitrate ions was observed for dabigatran and apixaban dissolved in a mineral water. The photosensitized reactions were limited in the tested river water (Isle River, Périgueux, France) certainly due to the hydroxyl radical scavenging effect of the dissolved organic matter. The study of photoproduct structures allowed to identify two compounds for dabigatran. One of them is the 4-aminobenzamidine while the second one is a cyclization product. In the case of rivaroxaban, as studied by very high field NMR, only one photoproduct was observed i.e. a photoisomer. Finally, seven photoproducts were clearly identified from the degradation of apixaban under simulated solar light.


Asunto(s)
Anticoagulantes/efectos de la radiación , Agua Dulce/química , Fotólisis/efectos de la radiación , Luz Solar , Benzamidinas , Francia , Radical Hidroxilo , Cinética , Pirazoles , Piridonas , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/efectos de la radiación
5.
J Chromatogr A ; 1513: 107-117, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28743395

RESUMEN

We report on a fast, accurate and rugged analytical procedure to determine a wide span of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in seabird plasma. The 26 investigated compounds included perfluoroalkyl carboxylates (C5-C14 PFCAs), perfluoroalkyl sulfonates (C4, C6, C7, C8, C10 PFSAs), perfluorooctane sulfonamide (FOSA) and N-alkyl derivatives (MeFOSA, EtFOSA), N-alkyl perfluorooctane sulfonamido acetic acids (MeFOSAA, EtFOSAA), fluorotelomer sulfonates (4:2 FTSA, 6:2 FTSA, 8:2 FTSA), polyfluoroalkyl phosphate diesters (diPAPs) and perfluorooctane sulfonamide phosphate diester (diSAmPAP). The method described herein requires a reduced sample amount (25µL) and involves rapid and simple sample preparation (protein precipitation with acetonitrile but without acidification) prior to analysis by on-line solid phase extraction (Oasis HLB sorbent) coupled to high performance liquid chromatography negative electrospray ionization tandem mass spectrometry. The optimization was conducted using experimental designs to account for potential interactions between variables. Out of the 26 target analytes, 23 compounds showed excellent accuracy (±25% of the expected values). Intermediate precision and matrix effects remained acceptable for most analytes thanks to efficient internal standardization. A human serum standard reference material (NIST SRM 1957) was included in the validation scheme to evaluate method trueness, which proved satisfactory (│Z-scores│<2 for most compounds). Notwithstanding the small initial sample intake, limits of detection as low as 0.003-0.1ngg-1 plasma were obtained. This allowed the determination of 11 target PFASs in Antarctic seabird plasma samples. ΣPFASs in Antarctic seabird plasma ranged from 0.37 to 19ngg-1, with a predominance of PFOS (>54% of ΣPFASs on average). The reduced plasma amount required implies that the present method could also be applied to the analysis of PFASs in the plasma of smaller biological models.


Asunto(s)
Alcanosulfonatos/sangre , Charadriiformes/sangre , Monitoreo del Ambiente/métodos , Sistemas en Línea , Espectrometría de Masas en Tándem/métodos , Alcanosulfonatos/análisis , Animales , Regiones Antárticas , Calibración , Cromatografía Líquida de Alta Presión/métodos , Fluorocarburos/sangre , Límite de Detección , Océanos y Mares , Extracción en Fase Sólida , Factores de Tiempo
6.
Sci Total Environ ; 607-608: 243-252, 2017 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-28692894

RESUMEN

The occurrence and spatial distribution of 22 selected perfluoroalkyl and polyfluoroalkyl substances (PFASs) in surface water (n=75), groundwater (n=80) and surficial sediment (n=15) were investigated for the first time in the tropical areas constituted by the French Overseas Territories (French Guiana, Guadeloupe, Martinique, Mayotte and Reunion). Descriptive statistics and correlations between PFASs were evaluated through the use of specific statistical treatments to handle left-censored data ("non-detects"). PFASs were ubiquitous in these samples and detection frequencies as high as 79% for perfluorooctane sulfonate (PFOS) and 65% for perfluorooctanoate (PFOA) were reported in surface waters. ∑PFASs was in the range

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