Evidence for a Complex Relationship between Antibiotics and Antibiotic-Resistant Escherichia Coli: From Medical Center Patients to a Receiving Environment
The aim of this study was to investigate the relationship between antibiotics and antibiotic-resistant fecal bacteria (E. coli) in water along a medical center−wastewater treatment plant−river continuum (4 km). A multiresidue chemical analysis methodology, using solid phase extraction coupled with liquid chromatography tandem mass spectrometry, was performed to detect whether low levels of contamination by 34 antibiotics were related to antibiotic resistance of E. coli and antibiotic use. The contamination of water by antibiotics and antibiotic-resistant E. coli decreased along the continuum. Although amoxicillin was predominantly prescribed, only ofloxacin (1 ng*L−1) and sulfamethoxazole (4 ng*L−1) persisted in the river. At the retirement home, in the medical center, even though no tetracycline and sulfamethoxazole were consumed, the highest occurrences of antibiotic resistance were in classes of quinolones (42.0%), sulfonamides (24.0%), tetracyclines (38.0%), and penicillins (38.0%), mainly due to the presenceof multiple antibiotic-resistance genes on class 1 integrons. Along the continuum, the occurrence of E. coli resistant to antibiotics and those carrying class 1 integrons decreased in water samples (p-value <0.001). Interestingly, in the river, only persistent antibiotic compounds (ofloxacin, sulfamethoxazole) were found, but they did not correspond to the major resistances (tetracycline, amoxicillin) of E. coli.
(Environmental Science and Technology. vol. 46, n° 0013-936X, pp. 1859−1868, 28/10/2026)
M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, SCALE, ULH, NU, UNIROUEN, NU, CNRS
La variabilité climatique rapide de la dernière période glaciaire et l’extinction des Néandertaliens
(pp. 107-121, 28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, PACEA, UB, CNRS
Influence of Hydrological Parameters on Organohalogenated Micropollutant (Polybrominated Diphenyl Ethers and Polychlorinated Biphenyls) Behaviour in the Seine (France)
The temporal dynamics of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) were investigated in a heavily urbanized river (Seine River, Paris, France) from November 2009 to May 2010. Pollutant concentrations were in the range of 0.2 to 3.8 ng l(-1) (median 1.1) and 0.4 to 3.6 ng l(-1) (median 1.1) for a tri-deca BDEs and a 7PCBs, respectively. In addition, for both PBDEs and PCBs, the partitioning between the particulate and dissolved phases was investigated. Due to their low water solubility, PBDEs were mainly (> 70%) bound to particles. In contrast, only 54% of a 7PCBs occurred in the particulate phase, and their partitioning was influenced by the degree of chlorination. During the sampling period, PBDE/PCB fluxes were quite similar and ranged from 3 to 128 and from 6 to 125 g day(-1), respectively. The annual mass flow of PBDEs and PCBs was estimated to 10 kg for both. Contrary to PCBs and BDE-209, the temporal evolution of a tri-hepta BDEs was related to particulate organic matter content, which is controlled by river flow variations. This suggests that they exhibit different sources or behavior in the Seine River.
(Archives of Environmental Contamination and Toxicology. vol. 62, n° 0090-4341, pp. 570-578, 28/10/2026)
SISYPHE, UPMC, EPHE, PSL, PSL, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Barred-beach morphological control on infragravity motion
A conceptual analysis of the coupling between bars and infragravity waves is performed combining laboratory experiments and numerical modeling. Experiments are carried out in a wave flume with a barred profile. The Boussinesq fully-nonlinear model SERR1D is validated with the laboratory data and a sensitivity analysis is performed next to study the influence on the infragravity wave dynamics of bar amplitude and location, and swash zone slope. A novel technique of incident and reflected motions separation that conserves temporal characteristics is applied. We observe that changing bar characteristics induces substantial variations in trapped energy. Interestingly, a modification of swash zone slope has a large influence on the reflected component, controlling amplitude and phase time-lag, and consequently on the resonant pattern. Variations of trapped infragravity energy induced by changes of swash zone slope reach 25 %. These changes in infragravity pattern consequently affect short-wave dynamics by modifying the breakpoint location and the breaking intensity. Our conceptual investigation suggests the existence of a morphological feedback through the action of evolving morphology on infragravity structures which modulates the action of short-waves on the morphology itself.
(pp. currents.24, 28/10/2026)
LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, PUC, UTFSM, LEGI, UJF, Grenoble INP, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Vegetation dynamics in the Northeastern Mediterranean region during the past 23 000 yr: insights from a new pollen record from the Sea of Marmara
Abstract. High-resolution pollen analysis of core MD01-2430 from the Sea of Marmara (40°47.81' N, 27°43.51' E) allows us to reconstruct the vegetation response to climatic changes during the past 23 cal ka in the Northeastern Mediterranean. Variation in mesic/temperate forest cover indicates major climatic shifts connected to Heinrich Stadial 1, Bölling-Allerød, Younger Dryas and to the onset of the Holocene. Pollen–anthropogenic indicator approach was used to recognize human-induced landscape changes in the Sea of Marmara. The pollen-inferred onset of the Holocene occurs at ca. 11.5 cal ka, indicating that the Northeastern Mediterranean region represents a transitional zone where higher moisture availability supported an earlier forest expansion than the borderlands of the Aegean Sea and Black Sea. Two major forest retreats occurred during the Holocene at ca. 5.5 and 2.1 cal ka. The Holocene forest setbacks are in phase with previously published alkenone-inferred sea-surface temperature decreases in the Sea of Marmara reconstructed from the same core. Our new pollen record testifies the sensitivity of Mediterranean forests to changes in moisture availability, which is driven by changes in high-latitude atmospheric processes (North Atlantic Oscillations and/or Siberian High).
(Climate of the Past. vol. 8, n° 1814-9324, pp. 1941-1956, 28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR ISEM, Cirad, IRD, EPHE, PSL, UM, CNRS
Assessing the effect of macrobenthos diversity on the mineralisation of sediment organic matter
(28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LGE, UPD7, IPG Paris, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, IPGP, INSU - CNRS, UPD7, UR, IPG Paris, CNRS, LOBB, OOB, UPMC, CNRS, UPMC, INSU - CNRS, CNRS, OOB, SU, CNRS, CNRS
Sedimentary processes in the Cap-Ferret canyon (Bay of Biscay, NE Atlantic): from seasonal to century time scales
(28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UCAD, LPG-ANGERS, LPG, UA, UN UFR ST, UN, INSU - CNRS, CNRS, JAMSTEC
Synergie de l’imagerie satellitaire optique et radar pour la cartographie des habitats du Bassin d'Arcachon
L’imagerie satellitaire optique dispose d’un bon potentiel de cartographie des espaces naturels littoraux de par l’emprise spatiale, la haute résolution et le recul temporel qu’offrent les 25 ans d’archives image SPOT. Cet article explore le potentiel des images SAR (Synthetic Aperture Radar) Haute Résolution (HR) pour la cartographie des habitats intertidaux en complément de l’imagerie optique traditionnelle. Dans un premier temps, l’article évalue le potentiel de discrimination des habitats du Bassin d’Arcachon à partir d’une série temporelle constituée de 15 images TerraSAR-X et de 2 images ALOS-PALSAR acquises entre 2007 et 2011. L’étude a permis de caractériser les signatures radar de la couverture sédimentaire intertidale, des herbiers de zostères, des bancs d’huitres et de la végétation du schorre. Les bancs d’huîtres, les structures ostréicoles et le schorre ont des signatures radar très particulières (forte brillance) ce qui permet de les distinguer de la slikke, qu’elle soit végétalisée ou non, et de lever la confusion issue de l’analyse d’une image optique seule. Dans un second temps, l’article développe les résultats issus de la classification des données optiques et radar concaténées sur le secteur de La Hume. Les résultats les plus satisfaisants sont obtenus avec une classification supervisée de Mahalanobis basée sur les 4 bandes SPOT d’une image estivale, la bande XS2 d’une image SPOT d’hiver et une bande radar HH TerraSAR-X. Cette approche cartographique combinant données optiques-radar multi-temporelles permet de lever les principales difficultés ayant motivé cette étude. Des développements sont toutefois encore nécessaires pour parvenir à mieux cartographier les grands ensembles végétaux du schorre et à détecter les biofilms à microphytobenthos ainsi que les dépôts de macro-algues.
(pp. 10, 28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMR TETIS, Cirad, IRSTEA
Reduction of refractory micropollutants in treated wastewater by advanced tertiary treatments
Some refractory micropollutants remain in treated wastewater after secondary treatments. In order to reduce their concentration in treated water, tertiary treatments can be used such as advanced oxidation processes and activated carbon. The efficiency of granular activated carbon in a long term is not well known and advanced oxidation processes have mostly been studied at laboratory scale. Advanced oxidation processes and granular activated carbon pilots were studied in two different wastewater treatment plants in order to determine their efficiency on numerous micropollutants. Both processes were efficient (>90%) on beta blockers and other drugs. The removal of alkylphenols was not complete with UV and hydrogen peroxide. Activated carbon was still efficient after six months functioning 24/24.
(pp. 4, 28/10/2026)
IRSTEA, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR MALY, IRSTEA
Effects of Methylmercury Contained in a Diet Mimicking the Wayana Amerindians Contamination through Fish Consumption: Mercury Accumulation, Metallothionein Induction, Gene Expression Variations, and Role of the Chemokine CCL2.
Methylmercury (MeHg) is a potent neurotoxin, and human beings are mainly exposed to this pollutant through fish consumption. We addressed the question of whether a diet mimicking the fish consumption of Wayanas Amerindians from French Guiana could result in observable adverse effects in mice. Wayanas adult men are subjected to a mean mercurial dose of 7 g Hg/week/kg of body weight. We decided to supplement a vegetarian-based mice diet with 0.1% of lyophilized Hoplias aimara fish, which Wayanas are fond of and equivalent to the same dose as that afflicting the Wayanas Amerindians. Total mercury contents were 1.4 ± 0.2 and 5.4 ± 0.5 ng Hg/g of food pellets for the control and aimara diets, respectively. After 14 months of exposure, the body parts and tissues displaying the highest mercury concentration on a dry weight (dw) basis were hair (733 ng/g) and kidney (511 ng/g), followed by the liver (77 ng/g). Surprisingly, despite the fact that MeHg is a neurotoxic compound, the brain accumulated low levels of mercury (35 ng/g in the cortex). The metallothionein (MT) protein concentration only increased in those tissues (kidney, muscles) in which MeHg demethylation had occurred. This can be taken as a molecular sign of divalent mercurial contamination since only Hg(2+) has been reported yet to induce MT accumulation in contaminated tissues. The suppression of the synthesis of the chemokine CCL2 in the corresponding knockout (KO) mice resulted in important changes in gene expression patterns in the liver and brain. After three months of exposure to an aimara-containing diet, eight of 10 genes selected (Sdhb, Cytb, Cox1, Sod1, Sod2, Mt2, Mdr1a and Bax) were repressed in wild-type mice liver whereas none presented a differential expression in KO Ccl2(-/-) mice. In the wild-type mice brain, six of 12 genes selected (Cytb, Cox1, Sod1, Sod2, Mdr1a and Bax) presented a stimulated expression, whereas all remained at the basal level of expression in KO Ccl2(-/-) mice. In the liver of aimara-fed mice, histological alterations were observed for an accumulated mercury concentration as low as 32 ng/g, dw, and metal deposits were observed within the cytoplasm of hepatic cells.
(International Journal of Molecular Sciences. vol. 13, n° 1661-6596, pp. 7710-38, 28/10/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UPMC, INSERM, CNRS, IBGC, UB, CNRS