Un projet intégratif en vue de protéger la qualité des eaux face aux usages de pesticides dans le vignoble Bordelais
Présentation du projet intégratif "PhytoCOTE" du LabEx COTE de l'Université de Bordeaux (coordination générale : Francis Macary) à la délégation mexicaine de scientifiques spécialisés sur la question de la protection de l'eau dans la zone métropolitaine de Léon.
(pp. 20, 26/04/2026)
UR ETBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Integration of contamination peaks with variable intensity and duration by the Polar Organic Chemical Integrative Sampler
Nowadays, pesticides, considering their efficiency on animal and plant parasites, represent considerable progress in food resources management and public health improvement. However, due to intensive use, the three environment compartments (water, air, soil) are contaminated with worrying consequences for human being and ecosystem. In order to conserve and restore the condition of aquatic environments, the European Water Framework Directive (WFD) was adopted in 2000 by the European Union. Indeed, monitoring networks - such as Water Agencies - proceed to regular monitoring, performing spot water sampling up to 12 times a year. But, there are still questions about the spatial and temporal representativeness of this type of sampling. Actually, contamination level in rivers can vary abruptly, depending on season and hydrology at the sampling moment. Thus, contamination peaks could be undetected by monitoring networks, generating a partial snapshot and then estimation of water quality. Passive sampling techniques are proposed and developed to obtain better representativeness of the contamination level, providing average concentration over time with integration of peculiar events like contamination peaks. In this study, the Polar Organic Chemical Integrative Sampler (POCIS) with different king of membranes was considered. This tool, widely used for polar pesticides sampling (0 < log Kow < 4) (Alvarez et al. 2004), allows pre-concentration in situ of analytes and presents an integrative capacity over several week. Its scope and its technical limitations are actually well documented (Lissalde et al. 2011). Furthermore, it was proved that this device may integrate contamination peaks relatively prolonged (about 3 days) for moderately polar compounds (log Kow = 2-3) (Mazzella et al. 2008). Concerning shorter contamination peaks (few hours-few days) generated by punctual pollutions, interrogations about its reactivity (e.g. lag time) is still remaining. This study aimed to show the POCIS reactivity for three different contamination peak patterns, with variable intensity and duration, over a total exposure period of 14 days. For this experimentation under laboratory controlled conditions, fifteen pesticides covering different polarities (log Kow=0-5) and groups (herbicides, fungicides, insecticides) were selected. The data showed different accumulation kinetic profiles, depending on physico-chemical characteristics of the substances and the exposition duration. Some compounds presented a lag effect, or on the contrary a burst effect. For seven compounds, POCIS sampled correctly contamination peaks, which show the ability of this device to sample fleeting events.
(pp. 39, 26/04/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Modelling the alongshore variability of optimum rip current escape strategies on a multiple rip-channelled beach
Rip currents are a leading cause of drowning on beaches worldwide. How bathers caught in a rip current should attempt to escape has been a subject of recent debate. A numerical model of human bathers escaping from a rip current flow field is applied to a 2-km long section of the open beach of Biscarrosse, SW France. The study area comprises 4 rip channels that visually appear similar from the beach, but exhibit different morphologies. Simulations are run for 2 representative hazardous summer wave conditions. Results show that small changes in the bar/rip morphology have a large impact on the rip flow field, and in turn on the alongshore variability of the optimal rip current escape strategy. The overall flow regime (dominant surf-zone exits versus dominant recirculation), which is found to be influenced by the alongshore dimensions of the sand bars adjacent to the rip channel, is more important to rip current escape strategy than rip velocity. Flow regime was found to dictate the success of the stay afloat strategy, with greater success for recirculating flow. By comparison, the dominant longshore feeder current and rip-neck orientation determined the best direction to swim parallel toward. For obliquely incident waves, swim parallel downdrift then swim onshore with breaking waves was highly successful and can become a simple safety message for beach safety practitioners to communicate to the general public. However, in SW France where rip spacing is large (∼400 m), surf-zone eddies have large spatial scales of the order of 100+ m, requiring a large distance (100+ m) to swim to reach safety, therefore requiring good swimming ability. This also shows that in addition to rip current intensity, rip flow regime and the depth of adjacent sand bars, rip spacing is important for defining rip current hazard and the best safety message. Our results also indicate that for normal to near-normal wave incidence, rip current hazard and best rip current escape strategy are highly variable alongshore due to subtle differences in bar/rip morphology from one rip system to another. These findings challenge the objective of developing a universal rip current escape strategy message on open rip-channelled beaches exposed to normal to near-normal wave incidence, even for seemingly similar rip channels.
(Natural Hazards. vol. 81, n° 0921-030X, pp. 663-686, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UNSW
Spatio-temporal dynamics of per and polyfluoroalkyl substances (PFASs) and transfer to periphytic biofilm in an urban river: case-study on the River Seine
Abstract 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.
(Environmental Science and Pollution Research. vol. 25, n° 0944-1344, pp. 1-9, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR HBAN, IRSTEA
Ideas and perspectives: Southwestern tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica
Recent Southern Hemisphere (SH) atmospheric circulation, predominantly driven by stratospheric ozone depletion over Antarctica, has caused changes in climate across the extratropics. Here, we present evidence that the Brazilian coast (southwestern Atlantic) may have been impacted from both wind and sea-surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air–sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.
(Biogeosciences. vol. 13, n° 1726-4170, pp. 2379-2386, 26/04/2026)
LARAMG, UERJ, USP, BTP, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NTU
Ideas and perspectives : Southwestern tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica
Recent Southern Hemisphere (SH) atmospheric circulation, predominantly driven by stratospheric ozone depletion over Antarctica, has caused changes in climate across the extratropics. Here, we present evidence that the Brazilian coast (southwestern Atlantic) may have been impacted from both wind and sea-surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air–sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.
(Biogeosciences Discussions. vol. 12, n° 1810-6277, pp. 13193-13213, 26/04/2026)
LARAMG, UERJ, USP, BTP, LOCEAN, IPSL, ENS-PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS, Departamento de Geoquímica, UFF, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, NTU, IRD [Ile-de-France]
Conditions for tidal bore formation in convergent alluvial estuaries
(Estuarine, Coastal and Shelf Science. vol. 172, n° 0272-7714, pp. 121 - 127, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CARDAMOM, IMB, UB, Bordeaux INP, CNRS, Inria
Elimination de micropolluants prioritaires et émergents des eaux résiduaires urbaines par les bioréacteurs à membranes immergées (BRM). Rapport final de l’action 34
La technologie de traitement des eaux usées domestiques par bioréacteurs à membranes (BRM) immergées se développe fortement en France pour équiper les stations de traitement des eaux usées domestiques. La présente étude vise à déterminer les avantages des BRM vis-à-vis de l’élimination des substances prioritaires et émergentes. Dans ce but, des campagnes d’échantillonnage ont été réalisées par temps sec sur trois installations équipées de bioréacteurs à membranes à fibres creuses ou bien à membranes planes. Des expérimentations en réacteur séparé (boues dopées en micropolluants placées en conditions contrôlées) ont permis de préciser les processus de sorption et de biodégradation des micropolluants, en vue d’une modélisation de l’élimination. Au total, 24 métaux et 66 substances organiques ont été analysés (hydrocarbures aromatiques polycycliques, alkylphénols, pesticides, substances pharmaceutiques et hormones) par des méthodes analytiques robustes et sensibles. Les rendements de la file Eau ont été déterminés pour 61 micropolluants : 43 micropolluants ont été bien à très bien éliminés de l'eau (> 70%, voire > 90%), dont le cuivre, le plomb, le chrome, le nickel, le zinc, ainsi que plusieurs HAP, alkylphénols, médicaments et hormones, soit par piégeage des matières en suspension et transfert dans les boues, soit par biodégradation. 26 micropolluants ont été partiellement à faiblement éliminés (< 70%, voire < 30%), dont l’arsenic et le cadmium, ainsi que plusieurs micropolluants organiques y compris 7 médicaments (propranolol, sotalol, roxithromycine, sulfaméthoxazole), fluoxétine, diclofénac, carbamazépine) et le diuron. La présente étude démontre que les BRM induisent une élimination supplémentaire pour 22 micropolluants par rapport aux procédés conventionnels comme les boues activées aération prolongée, mais ce gain d’élimination est faible (< 20%). Ce gain concerne certains des micropolluants généralement adsorbés aux matières en suspension (ex. certains métaux ou HAP), et quelques médicaments (i.e., sotalol, roxithromycine, propranolol, timolol). Pour 38 autres micropolluants (en particulier pour les hormones, les détergents et la majorité des pharmaceutiques d’origine domestique notamment le diclofénac), les performances d'élimination par les BRM sont similaires à celles des boues activées aération prolongée fonctionnant à charges massiques appliquées équivalentes (sous-chargées). Un modèle cinétique a été développé, et simule correctement les concentrations de 51 micropolluants dans les rejets de BRM. Nous estimons qu’une faible augmentation du rendement serait possible (jusqu’à 15 unités supplémentaires) pour 6 micropolluants seulement, ceci en augmentant la concentration en matières en suspension dans les BRM. Pour diminuer les concentrations des micropolluants les plus réfractaires (non adsorbables et/ou non biodégradables) dans les rejets, les actions de réduction à la source ou la mise en place de traitement complémentaire sont donc indispensables, même pour les STEU équipées de BRM.
(pp. 105, 26/04/2026)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UB
Réponses adaptatives ou délétères des jeunes stades de l’esturgeon européen Acipenser sturio en conditions multi-stress
L’esturgeon européen Acipenser sturio est un poisson migrateur en danger critique d’extinction dont la dernière population sauvage fréquente l’estuaire de Gironde. Depuis 1994, aucune reproduction en milieu naturel n’a été observée. Un plan national d’action vise à soutenir cette population en déclin par le lâcher chaque année de plusieurs dizaines de milliers de larves et de juvéniles dans les eaux de Garonne et de Dordogne. Dans ce contexte, la survie de ces poissons produits en captivité dans les conditions environnementales actuelles et futures en Gironde. Ainsi que la capacité des frayères historiques à accueillir à nouveau une reproduction d’esturgeon européen, sont deux problématiques essentielles. Pour répondre à ces deux interrogations des expérimentations ont été conduites dans le cadre du projet Sturtop (financement ANR et région Aquitaine) afin d’évaluer les capacités adaptatives des embryons, larves et juvéniles de A. sturio à la température, l’hypoxie, les polluants et la qualité des sédiments de frayère. Les résultats obtenus démontrent que les embryons et larves sont beaucoup plus sensibles aux hautes et basses températures (23°C) et aux conditions hypoxiques (
(pp. 29, 26/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR EABX, IRSTEA, CNRS, INRA
Differential protein expression in the estuarine copepod Eurytemora affinis after diuron and alkylphenol exposures
Proteomics was used in the calanoid copepod Eurytemora affinis for screening of protein expression modifications induced by organic contaminants. The copepods were exposed in a continuous flow-through system for 86 h to environmentally relevant concentrations of contaminants representative of the pollution in the Seine Estuary (Haute-Normandie, France; diuron, 500 ng L−1; alkylphenol mixture, 1000 ng L−1). Proteome analysis of whole-body copepod extracts by 2-dimensional gel electrophoresis revealed that the contaminants induced modifications in protein expression, with the highest quantitative variations occurring after diuron exposure. Specifically, 88 and 41 proteins were differentially expressed after diuron and alkylphenol treatments, respectively. After mass spectrometry analysis, 51 (diuron exposure) and 15 (alkylphenol exposure) proteins were identified. The identified proteins were potentially related to energy metabolism, cell growth, nervous signal conductivity, excitotoxicity, oxidative stress response, and antioxidant defense. The data suggest a massive general disturbance of physiological functions of E. affinis after diuron exposure, whereas alkylphenols induced an alteration of a few targeted physiological functions. The protein expression signatures identified after contaminant exposure deserve further investigation in terms of the development of novel potential biomarkers for water quality assessment
(Environmental Toxicology and Chemistry. vol. 35, n° 0730-7268, pp. 1860 - 1871, 26/04/2026)
LEMA, ULH, NU, SEBIO, INERIS, URCA, ULH, NU, URCA, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LOG, INSU - CNRS, ULCO, CNRS, IRD [Ile-de-France], PBS, UNIROUEN, NU, INSA Rouen Normandie, INSA, NU, INC3M, UNICAEN, NU, ENSICAEN, NU, ULH, NU, UNIROUEN, NU, INSA Rouen Normandie, INSA, NU, INC-CNRS, CNRS, INC-CNRS, CNRS