Evaluation of advanced oxidation processes for the reduction of refractory micropollutants in treated wastewater
Complementary treatments can allow a reduction of concentrations of micropollutants to reach values compatible with a good state of the environment. Processes that seem more efficient to eliminate refractory substances from treated wastewater are advanced technologies similar to the ones used for drinking water production : ozonation, UV light, adsorption on activated carbon, membranes and advanced oxidation processes. Advanced oxidation processes (AOP) rely on the formation of HO° radical witch is less selective than ozone and has higher reaction constants. An advanced oxidation processes pilot was tested in two plants. The AOP pilot is a container with two reactors in parallel (O3/H2O2 and O3/H2O2/UV). Mass balances were performed based on wastewater flow and micropollutants concentration data at the inlet and at the outlet of the studied processes. All advanced oxidation processes tested were efficient on beta blockers and other drugs (>90%). The removal of alkylphenols was not complete with UV and hydrogen peroxide.
(pp. 2, 13/04/2026)
IRSTEA, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR MALY, IRSTEA
Mass wasting processes along the Owen Ridge (Northwest Indian Ocean)
The Owen Ridge is a prominent relief that runs parallel to the coast of Oman in the NW Indian Ocean and is closely linked to the Owen Fracture Zone, an 800-km- long active fault system that accommodates today the Arabia-India strike-slip motion. Several types of mass failures mobilizing the pelagic cover have been mapped in details along the ridge using multibeam bathymetry and sediment echosounder. Here we present a synthetic map of the different types of mass wasting features observed along the ridge and we further establish a morphometric analysis of submarine landslides. The spatial variation of failure morphology is strongly related to the topography of the basement. The highest volumes of multi-events generated slides are mobilized along the southern portion of the ridge. There, the estimated volume of evacuated material during a slide is up to 45 km3. Combining these new observations with re-interpreted ODP seismic lines (Leg 117) documents sporadic mass wasting events through time along the southern segment of the ridge since its uplift in the Early Miocene, with a typical recurrence rate of the order of 105-106 years. Although seismicity may still be the final triggering process, mass wasting frequency is mainly controlled by the slow pelagic sedimentation rates and hence, time needed to build up the 40-80 m thick pelagic cover required to return to a mechanically unstable pelagic cover .
(Marine Geology, n° 0025-3227, pp. 1-21, 13/04/2026)
iSTeP, UPMC, CNRS, LGENS, INSU - CNRS, CNRS, ENS-PSL, PSL, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Etude intégrée de l’effet des apports amont et locaux sur le fonctionnement de la Garonne estuarienne (ETIAGE) : Rapport de synthèse année 1 Avril 2010 - Mars 2011
Le programme ETIAGE a été mis en place avec pour objectif de répondre aux questions suivantes : que représentent les apports des effluents de la Communauté Urbaine de Bordeaux (CUB) par rapport à ceux venant de l’amont en termes de charge organique et de micro-polluants ? Quels rôles sur le devenir des effluents jouent la présence du bouchon vaseux et la stagnation résiduelle des eaux (déplacement net entre mouvement de flot et de jusant) au niveau de l’estuaire fluvial amont en période d’étiage estival ? Réciproquement, à quels moments et jusqu’où s’étend l’impact de ces effluents sur la qualité des eaux de la Garonne estuarienne ? Quelles incidences des effluents sur le comportement des populations biologiques en place ou migratoires dans la Garonne estuarienne ? Quelle tendance évolutive va connaître l’oxygénation des eaux ? Quel sera l’impact sur le comportement des micro-polluants et des populations biologiques ? Quelles recommandations de gestion pourraient être préconisées à partir de la synthèse des pressions exercées sur les eaux de la Garonne estuarienne ? Le programme est divisé en 5 axes, dont les bilans de travail sont présentés axe par axe pour l’année 1, couvrant la période Avril 2010 – Mars 2011.
(pp. 36, 13/04/2026)
UR EPBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Agulhas leakage as a key process in the modes of Quaternary climate changes
Heat and salt transfer from the Indian Ocean to the Atlantic Ocean (Agulhas leakage) has an important effect on the global thermo-haline circulation and climate. The lack of long transfer record prevents elucidation of its role on climate changes throughout the Quaternary. Here, we present a 1,350-ka accumulation rate record of the planktic foraminiferal species Globorotalia menardii. We demonstrate that, according to previous assumptions, the presence and reseeding of this fauna in the subtropical southeast Atlantic was driven by interocean exchange south of Africa. The Agulhas transfer strengthened at glacial ice-volume maxima for every glacial-interglacial transition, with maximum reinforcements organized according to a 400-ka periodicity. The long-term dynamics of Agulhas leakage may have played a crucial role in regulating meridional overturning circulation and global climate changes during the Mid-Brunhes event and the Mid-Pleistocene transition, and could also play an important role in the near future.
(Proceedings of the National Academy of Sciences of the United States of America. vol. 109, n° 0027-8424, pp. 6835-6839, 13/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LOCEAN, IPSL, ENS-PSL, PSL, UVSQ, UPMC, CEA, INSU - CNRS, X, IP Paris, CNES, CNRS, MNHN, IRD, UPMC, INSU - CNRS, CNRS
Événements extrêmes (submersion estuarienne et crue) dans le Médoc viticole : Quels changements environnementaux pour la qualité géochimique des eaux de l’estuaire de la Gironde ?
L’estuaire de la Gironde (sud-ouest de la France) a été marqué au cours de ces dernières décennies par des événements météorologiques majeurs (Tempêtes Martin en 1999, Xynthia en 2010), responsables d’importantes inondations (submersions estuariennes et crues). Dans un contexte de changements globaux (augmentation du niveau de la mer, urbanisation croissante, …), des incertitudes persistent quant à la fréquence de ces événements. A ces incertitudes s’ajoute une méconnaissance des impacts géochimiques sur la qualité des sols et des eaux de l’estuaire, consécutifs à la remise en eau temporaire des terrains riverains principalement viticoles, pouvant être fortement contaminés en certains métaux. A partir d’une base de données existantes sur les catastrophes naturelles (GASPAR) et d’une base météorologique, nous avons identifié les communes les plus sinistrées du Médoc sur lesquelles nous avons collecté des sols qui ont subi des tests de lixiviation en laboratoire. Pour cela, les sols ont été mis au contact avec de l’eau douce ou estuarienne afin d’identifier les processus de relargages ou piégeages en métaux et simuler, ainsi, l’impact des inondations. Les paramètres des tests de lixiviation ont été déterminés à partir de la détermination des caractéristiques des événements (type, durée, saison). Cette étude s’inscrit dans un programme de recherche pluridisciplinaire Adapt’eau (ANR CEP&S 2011), qui vise à étudier les impacts des changements globaux et à expérimenter des options d’adaptation sur l’environnement fluvio-estuarien Garonne-Gironde, notamment la dépoldérisation. Dans cette perspective, notre recherche apporte des éléments d’éclairage sur l’impact de la remise en eaux des terres viticoles sur la Garonne-Gironde.
(pp. 17, 13/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR ADBX, IRSTEA
Responses and structural recovery of periphytic diatom communities after short-term disturbance in some rivers (Hanoi, Vietnam)
Field transfer experiments of periphytic diatom assemblages developed on artificial substrates were set up to assess the responses of those communities to environmental disturbances. The glass slides were positioned for colonization at the relatively unpolluted site (Red, in the Red River) and at the heavily polluted site (TL, in the To Lich River) in the beginning of the experiment. After a period of 2 weeks, the colonized glass slides were concomitantly transferred from the unpolluted Red site to the heavily polluted TL site and to the moderate polluted site (NT 2, in the Nhue River) and, conversely, from the TL site to the Red site, and then to the NT 2 site. The responses and the adapting capacity of periphytic diatom communities to environmental changes were assessed through the cell density, diversity index, species richness, taxonomic composition, and diatom indices after 2 and 4 weeks of transfer periods. For all transfers except for the transfer from the Red to the TL site in which the growth inhibition of diatom cells was found, the diatom density significantly increased until the end of the experiment. Thus, the diatom communities have expressed their pollution tolerance or sensitivities by changing their composition to adapt themselves to environmental changes. Characteristic species of the Red site (Gyrosigma scalproides, Navicula recens) were replaced by Nitzschia palea, Nitzschia umbonata, Aulacoseira granulate typical species of the NT 2 site, in the biofilm transferred from the Red site to the NT 2 site. The relative abundances of typical diatom species of the Red site proliferated in the biofilm transferred from the TL site to the Red site. The replacement of periphytic diatom communities appeared after the transfer from the second week at the different sites. The slow shift of the species towards the typical species at the TL site could result from the organized structure of diatoms within biofilm before the transfer from the Red site to the TL site. The shifts in values of the Index of Specific Polluosensitivity and Diatom Assemblage Index to organic pollution throughout the experiment indicated the clear sensitivity of these indices to water quality changes.
(Journal of Applied Phycology. vol. 24, n° 0921-8971, pp. 1053-1065, 13/04/2026)
IRSTEA, UR REBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IRSTEA
L'hydrodynamique du lagon sud-ouest
La circulation des eaux dans le lagon sud-ouest Nouvelle-Calédonie est due à trois agents principaux : la marée, le vent local et le déferlement la houle par-dessus le récif-barrière.
(pp. p. 41-44., 13/04/2026)
UAM, ECOLA, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Effects of copper and cadmium spiked-sediments on embryonic development of Japanese medaka (Oryzias latipes)
Because of their high capacity to accumulate contaminants such as persistent organic pollutants and heavy metals, aquatic sediments are considered as a long-term source of contamination for aquatic organisms. In compliance with the increasing interest both for sediment quality evaluation and the use of fish early life stage (ELS) toxicity assays, we proposed an embryo-larval test to evaluate embryotoxicity and genotoxicity of sediment-bound contaminants. Pre-blastula stage medaka (Oryzias latipes) embryos were exposed by static sediment contact to two model heavy metals (cadmium and copper) at environmental concentrations during the whole 10-day embryonic development. Lethal and sub-lethal effects were recorded in both embryos and larvae for 20 days post fertilisation (dpf) using several global toxicity and phenotypic endpoints. The comet assay was also performed on medaka prolarvae to evaluate genotoxic effects of the tested chemicals. Environmental concentrations of cadmium (Cd) and copper (Cu) did not affect embryo and larval survival. However, both heavy metals significantly induced morphological abnormalities, particularly spinal and cardiovascular deformities. Cd but not Cu induced tachycardia. Both heavy metals induced a significant increase in DNA damage at all tested concentrations. Resulting LOEC values for Cd and Cu corresponded to 1.9 and 8.5 μg/g d.w. sediment, respectively. Although metal bioavailability is probably lower for naturally contaminated sediments, the relatively low toxicity thresholds for both Cd and Cu raise the question of possible risk for fish embryos developing in direct contact to sediments. This study demonstrates the applicability, sensitivity and relevance of the Japanese medaka embryo-larval assay (MELA) to evaluate sediment hazardous potency at environmental concentrations of heavy metals.
(Ecotoxicology and Environmental Safety. vol. 79, n° 0147-6513, pp. 272-282, 13/04/2026)
SEBIO, INERIS, URCA, ULH, NU, URCA, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Embryotoxic and genotoxic effects of heavy metals and pesticides on early life stages of Pacific oyster (Crassostrea gigas)
This study evaluated embryotoxicity and genotoxicity of two dissolved metals copper and cadmium (Cu and Cd) and two pesticides (metolachlor and irgarol) occurring in Arcachon Bay (SW France) in Pacific oyster (Crassostrea gigas) larvae and investigated the relationship between those two endpoints. Embryotoxicity was measured by calculating the percentage of abnormal D-shaped larvae and genotoxicity was evaluated with DNA strand breaks using the comet assay. After 24 h exposure, significant increases of the percentage of abnormal D-larvae and the DNA strand breaks were observed from 0.1µg/L for Cu, 10 µg/L for Cd and 0.01 µg/L for both irgarol and metolachlor in comparison with the controls. A strong positive relationship between embryotoxicity and genotoxicity was recorded for Cu, Cd and metolachlor. The current study suggests that copper, irgarol and metolachlor can induce larval abnormalities and DNA damage in a population of exposed oysters at environmentally relevant concentrations.
(Marine Pollution Bulletin. vol. 64, n° 0025-326X, pp. 2663-2670, 13/04/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR MALY, IRSTEA
Evaluation of the efficiency of wastewater advanced treatments and sludge treatments through chemical analysis of 168 selected compounds and non-target analysis
The general objective of the ECHIBIOTEB research program (“Innovating tools for sampling, chemical and biological analyses for the diagnosis of wastewater advanced tertiary treatments and sludge treatments”, 2011-2014, financed by the French National Research Agency, coordinated by Irstea) is to use innovative and complementary tools to characterize the efficiency of water advanced treatments and sludge treatments in wastewater treatment plant. To achieve this goal, various strategies were combined: chemical analysis of a large panel of selected priority and emerging contaminants, non-target chemical analysis, in vitro and in vivo biological analysis and innovating sampling tools such as integrative samplers (e.g. POCIS (Polar Organic Chemical Integrative Sampler) and SPMD (Semi-Permeable Membrane Device)). Our presentation will focus on results on the chemical analyses of selected molecules and non-target analysis. Until today, 11 sampling campaigns, 8 for water and 3 for sludge, have been conducted. Among the potential treatments used for advanced (or tertiary) water treatments, ozone (O3), Granular Activated Carbon (GAC), O3 + GAC, ozone peroxide (H2O2) and UV/H2O2 were studied in full scale or large scale pilot design, located on the outlet of secondary biological treatments. For sludge treatments, solar dryer, compost and reed-bed filter were tested. A total of 138 contaminants belonging to pharmaceuticals, oestrogenic hormones, alkylphenols (AkP), Endocrine Disruptor Compounds (EDC), Polycyclic Aromatic Hydrocarbons (PAH) and pesticides were measured in the dissolved phase of water samples; and 113 contaminants, belonging to pharmaceuticals, oestrogenic hormones, AkP, EDC, organochlorine pesticides, PAH, PCB (PolyChloroBiphenyl) and PBDE (PolyBrominated DiphenylEthers) were measured in sludge samples. After extraction by adapted methods such as Liquid-Liquid Extraction, Solid Phase Extraction or Solid Phase MicroExtraction for waters, and Accelerated Solvent Extraction or microwave extraction for sludge, molecules were analysed by gas (GC) or liquid phase chromatography coupled with single or tandem mass spectrometry. Non-target analysis were realised with two-dimensional GC coupled to Time Of Flight mass spectrometer. For most of the compounds, targeted analysis showed a significant reduction in contaminant concentration in the dissolved phase of water after all tested treatments. Indeed, pharmaceuticals and AkP were efficiently eliminated with concentrations in effluents respectively about 100 and 10 times lower than in influents. In contrast, aminomethylphosphonic acid (AMPA) and glyphosate were not eliminated at all from secondary wastewaters. Many of the selected compounds are refractory to conventional secondary treatments; nonetheless, we demonstrated that they can be efficiently removed thanks to selected advanced tertiary treatments. In the presentation, we will discuss which treatment seems to be the most efficient to eliminate the selected compounds. Depending on the process and the contaminant class, concentrations in raw and treated sludge varied widely. Non-target analyses of 3 different sludge samples allowed to obtain a list of 190 molecules of interest, among which some nitrogen heterocyclic compounds as potential emerging contaminants. Further investigations are needed, especially combining chemical with biological analysis, to determine which compounds among these 190 would be the most relevant to be considered in environmental studies.
(pp. 19, 13/04/2026)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS