Malmgrenia louiseae sp. nov., a new scale worm species (Polychaeta: Polynoidae) from southern Europe with a key to European Malmgrenia species
Malmgrenia louiseae sp. nov. is described from both the Western Mediterranean in the Gulf of Lions, and the Northeast Atlantic from off Portugal and the Bay of Biscay. The species was found in muddy sediments in shallow water and is possibly associated with echiurids or synaptid holothurians. Malmgrenia louiseae sp. nov. can be clearly distinguished from all other known Malmgrenia species by the presence of an infra-acicular process in addition to the supra-acicular process on the acicular lobe of the neuropodia, the lack of microtubercules on the elytra, two kinds of notochaetae (stout with blunt tip and slender with fine pointed tip), and exclusively unidentate neurochaetae. An identification key to the Northeast Atlantic and Mediterranean Malmgrenia species is provided.
(Journal of the Marine Biological Association of the United Kingdom. vol. 95, n° 0025-3154, pp. 947-952, 26/10/2026)
LIENSs, INSU - CNRS, ULR, CNRS, CESAM, Thomson Unicomarine, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LECOB, OOB, UPMC, CNRS, UPMC, CNRS
The region of the Strandja Sill (North Turkey) and the Messinian events
The two sides of the Strandja Sill show a highly discontinuous stratigraphic succession since the Late Oligocene. This area, together with the Sea of Marmara Basin, is usually proposed as the gateway for the Paratethyan freshwaters and organisms that constituted the Lago Mare facies in the Mediterranean Sea during the Messinian Salinity Crisis (MSC). Our investigations involving new field observations and datings, together with previous studies, suggest that the sill has possibly experienced such a connection at around 8 Ma, i.e. significantly before the crisis. The proposal of a sea-level drop of the Black Sea before 7 Ma is not supported by our data on dinoflagellate cysts. Consistency of calcareous nannofossil succession at DSDP Site 380 is reinforced, allowing to reassert that subaerial erosion impacted both the southwestern Black Sea and the central Marmara – Dardanelles area during the peak of the MSC. At that time, this region was crossed by two oppositely directed fluvial networks, further supporting the absence of a marine gateway through the Strandja Sill. It is concluded that none of the Lago Mare events recorded in the Mediterranean during the MSC were the consequence of the passage of Paratethyan waters and organisms through this area. In the Black Sea, the well-dated Messinian fluvial erosion can be followed offshore. The overlying prograding deltaic deposits attest to a fast marine reflooding after the crisis. This constitutes a comprehensive erosion-sedimentation model in an area intensively explored for hydrocarbons.
(Marine and Petroleum Geology. vol. 66, n° 0264-8172, pp. 149-164, 26/10/2026)
iSTeP, UPMC, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ITÜ, IFREMER, IPGP, INSU - CNRS, UPD7, UR, IPG Paris, CNRS, GeoEcoMar, CR2P, MNHN, UPMC, CNRS, CEREGE, IRD, INRA, AMU, CdF (institution), INSU - CNRS, CNRS, AYBE, ITÜ, Cerema, NIHWM
Photolysis of natural β-triketonic herbicides in water.
The fate of four natural β-triketones (leptospermone, isoleptospermone, grandiflorone and flavesone, pKa = 4.0–4.5) in aqueous solution, in the dark and upon simulated solar light irradiation was investigated. In anionic form, β-triketones undergo slow dark oxidation and photolysis with polychromatic quantum yields varying from 1.2 × 10−4 to 3.7 × 10−4. Leptospermone and grandiflorone are the most photolabile compounds. In molecular form, β-triketones are rather volatile. Polychromatic quantum yields between 1.2 × 10−3 and 1.8 × 10−3 could be measured for leptospermone and grandiflorone. They are 3–5 times higher than for the anionic forms. Photooxidation on the carbon atom bearing the acidic hydrogen atom is the main oxidation reaction, common to all the β-triketones whatever their ionization state. However, leptospermone shows a special photoreactivity. In molecular form, it mainly undergoes photoisomerization. Based on this work, the half-lives of β-triketones in surface waters should be comprised between 7 and 23 days.
(Water Research. vol. 78, n° 0043-1354, pp. 28-36, 26/10/2026)
ICCF, UBP, SIGMA Clermont, INC-CNRS, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Impact de deux antifouling, l’irgarol 1051 et le diuron sur la physiologie de deux souches de la micro-algue marine Tetraselmis suecica
L’irgarol 1051 (I) et le diuron (D) sont deux biocides couramment utilisés dans les peintures antifouling et les antimousses. Ils ciblent directement le photosystème II en inhibant le transfert d'électrons entre les quinones A et B. De par ce mode d’action, de nombreuses cibles indirectes peuvent être affectées en cas de contamination environnementale. Les effets de ces deux composés ont été étudiés, seuls et en mélange, sur deux souches d’une espèce de phytoplancton marin, Tetraselmis suecica : une souche "sauvage" (CCMP 904) (TS) et une souche résistante au diuron (TM) obtenue récemment au Laboratoire d’Ecotoxicologie (Stachowski-Haberkorn et al., 2013). Les effets des molécules ont été étudiés, chez les deux souches, sur la croissance, le rendement photosynthétique, la présence d'espèces réactives de l'oxygène (EROs, par cytométrie en flux) et le contenu relatif en lipides intracellulaires (cytométrie en flux) après une exposition de 6 jours. Les conditions d’exposition étaient les suivantes : I0.05, I0.1 et I0.5 μg.L-1 ; D0.5, D1 et D5 μg.L-1 ; quatre mélanges (en μg.L-1) MixA : D5 + I0.5 ; MixB : D5 + I0.1 ; MixC : D1 + I0.5 ; MixD : D1 + I0.1. En parallèle, le séquençage du gène psbA codant pour la protéine D1 du photosystème II (cible du diuron) a été entrepris sur les deux souches afin de déterminer l’origine de la résistance à la molécule chez la souche TM. Les résultats obtenus ont montré que le diuron avait induit des effets significatifs sur l’ensemble des paramètres étudiés de la souche TS à la concentration de 5 μg.L-1 : augmentation de 125% (± 2.3%) du temps de doublement, augmentation de 43% (± 1.8%) de la fluorescence relative à la présence d’EROs, diminution de 25% (± 1.8%) du rendement photosynthétique et de 38% (± 1.9%) du contenu lipidique relatif. L’irgarol à 0,5 μg.L-1, a également entraîné des effets significatifs sur l’ensemble des paramètres physiologiques : +19% (± 2%) sur le temps de doublement, +45% (± 4.6%) sur la fluorescence relative à la présence d’EROs, -2% (± 0.6%) sur l’efficacité de photosynthèse et -21% (± 1.3%) sur le contenu lipidique relatif. Suite à l’exposition de la souche aux quatre mélanges, les résultats ont montré des effets cumulés et progressifs (MixA> MixB> MixC> MixD) des molécules sur l’ensemble des paramètres. Pour la souche résistante au diuron, le séquençage de l’ARNm codant pour la protéine D1 a montré une mutation de G en A dans le domaine de liaison de la quinone à la position 661 de la séquence cds. Cette mutation correspond à un changement de la valine en isoleucine en position 221 dans la séquence d'acides aminés de la protéine. Cette mutation a permis à la souche de résister au diuron (aucun effet significatif enregistré quelle que soit la concentration d’exposition). Cependant, cette mutation n’a pas permis de résister à un herbicide au mode d’action similaire puisque l’irgarol à la concentration 0.5 μg.L-1 a engendré des effets délétères sur chacun des paramètres physiologiques : +19% (± 3.4%) sur le temps de doublement, +20% (± 5%) sur la fluorescence relative à la présence d’EROs, -8% (± 0.7%) sur l’efficacité de photosynthèse et -15% (± 2.8%) sur le contenu lipidique relatif. D’autre part, les résultats des expositions réalisées avec les mélanges ont montré des effets synergiques entre les deux molécules bien que le diuron seul n’ait pas eu d’effet (MixA> MixC> MixB> MixD). Ainsi, cette étude démontre la toxicité élevée de ces deux biocides pour l’espèce Tetraselmis suecica. Elle démontre également que la mutation mise en évidence, permettant une résistance au diuron, ne permet pas nécessairement une résistance à un autre inhibiteur du photosystème II. Elle souligne donc la nécessité (i) de considérer les mélanges dans l’évaluation de la toxicité des molécules et (ii) de surveiller le devenir dans l'environnement de ces deux composés encore autorisés dans de nombreux pays dont des pays européens (irgarol).
(pp. 34, 26/10/2026)
UR EABX, IRSTEA, IFREMER, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UB
Occurrence and Removal of Organic Micropollutants in Landfill Leachates Treated by Electrochemical Advanced Oxidation Processes
In recent years, electrochemical advanced oxidation processes have been shown to be an effective alternative for the removal of refractory organic compounds from water. This study is focused on the effective removal of recalcitrant organic matter (micropollutants, humic substances, etc.) present in municipal solid waste landfill leachates. A mixture of eight landfill leachates has been studied by the electro-Fenton process using a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode or by the anodic oxidation process with a BDD anode. These processes exhibit great oxidation ability due to the in situ production of hydroxyl radicals (OH), a highly powerful oxidizing species. Both electrochemical processes were shown to be efficient in the removal of dissolved total organic carbon (TOC) from landfill leachates. Regarding the electro-Fenton process, the replacement of the classical anode Pt by the anode BDD allows better performance in terms of dissolved TOC removal. The occurrence and removal yield of 19 polycyclic aromatic hydrocarbons, 15 volatile organic compounds, 7 alkylphenols, 7 polychlorobiphenyls, 5 organochlorine pesticides, and 2 polybrominated diphenyl ethers in landfill leachate were also investigated. Both electrochemical processes allow one to reach a quasicomplete removal (about 98%) of these organic micropollutants.
(Environmental Science and Technology. vol. 49, n° 0013-936X, pp. 12187-12196, 26/10/2026)
UPEM, IRSTEA, UR HBAN, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Is the toxicity of pesticide mixtures on river biofilm accounted for solely by the major compounds identified?
Pesticides are present as a cocktail of compounds at low concentrations in water bodies. Nevertheless, studies assessing the toxic effects of pesticide mixtures at realistic environmental concentrations are still scarce. Polar Organic Chemical Integrative Sampler (POCIS) allows the concentration of several organic chemicals from large volumes of natural water [1]. This high pre-concentration of compounds makes POCIS a powerful tool to assess extract toxicity via biological testing and therefore to study the impact of realistic mixtures . PE can be used as a black box with the advantages of dealing with mixtures “as they came”; this approach gives an estimation of an integrative measure of the toxic potential of a group of compounds including unknown toxicants without using an a priori approach. With this protocol, the global toxicity of the extract is assessed although the compounds responsible for the observed toxicity are not identified. The present study aimed to characterize the effects of long-term and low-dose exposure to POCIS extracts in a context of contamination by cereal crops on a natural biofilm community and to evaluate whether the effects observed due to exposure to PE were explained by the major compounds identified in the extracts [2].
(pp. 2, 26/10/2026)
UR EABX, IRSTEA, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Mercury mobilization and speciation linked to bacterial iron oxide and sulfate reduction: A column study to mimic reactive transfer in an anoxic aquifer
Mercury (Hg) mobility and speciation in subsurface aquifers is directly linked to its surrounding geochemical and microbial environment. The role of bacteria on Hg speciation (i.e., methylation, demethylation and reduction) is well documented, however little data is available on their impact on Hg mobility. The aim of this study was to test if (i) Hg mobility is due to either direct iron oxide reduction by iron reducing bacteria (IRB) or indirect iron reduction by sulfide produced by sulfate reducing bacteria (SRB), and (ii) to investigate its subsequent fate and speciation. Experiments were carried out in an original column setup combining geochemical and microbiological approaches that mimic an aquifer including an interface of iron-rich and iron depleted zones. Two identical glass columns containing iron oxides spiked with Hg(II) were submitted to (i) direct iron reduction by IRB and (ii) to indirect iron reduction by sulfides produced by SRB. Results show that in both columns Hg was leached and methylated during the height of bacterial activity. In the column where IRB are dominant, Hg methylation and leaching from the column was directly correlated to bacterial iron reduction (i.e., FeII release). In opposition, when SRB are dominant, produced sulfide induced indirect iron oxide reduction and rapid adsorption of leached Hg (or produced methylmercury) on neoformed iron sulfides (e.g., Mackinawite) or its precipitation as HgS. At the end of the SRB column experiment, when iron-oxide reduction was complete, filtered Hg and Fe concentrations increased at the outlet suggesting a leaching of Hg bound to FeS colloids that may be a dominant mechanism of Hg transport in aquifer environments. These experimental results highlight different biogeochemical mechanisms that can occur in stratified sub-surface aquifers where bacterial activities play a major role on Hg mobility and changes in speciation.
(Journal of Contaminant Hydrology. vol. 180, n° 0169-7722, pp. 56 - 68, 26/10/2026)
BRGM, UNIGE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Herbicide toxicity on river biofilms assessed by pulse amplitude modulated (PAM) fluorometry
The use of Rapid light curves (RLCs) as a toxicity endpoint for river biofilms was examined in this studyand compared to "classical fluorescence parameters" i.e. minimal fluorescence (F0), optimal and effectivequantum yields of photosystem II (Fv/Fmand PSII). Measurements were performed after exposure tofive concentrations of diuron (from 0.3 to 33.4 g L-1), its main degradation product (DCPMU) (from1.0 to 1014 g L-1) and norflurazon (from 0.6 to 585 g L-1) with the lowest exposure concentrationscorresponding to levels regularly encountered in chronically contaminated sites. Biofilm responses wereevaluated after 1, 5, 7 and 14 days of exposure to the different toxicants.Overall, the responses of both "classical fluorescence parameters" and RLC endpoints were highly timedependent and related to the mode of action of the different compounds. Interestingly, parameters cal-culated from RLCs (ETRmaxand Ik) were useful early markers of pesticide exposure since they revealedsignificant effects of all the tested toxicants from the first day of exposure. In comparison, classicalfluorescence endpoints (F0and Fv/Fm) measured at day 1 were only affected in the DCPMU treatment.Our results demonstrated the interest of RLCs as early markers of toxicant exposure particularly whenworking with toxicants with less specific mode of action than PSII inhibitors.
(Aquatic Toxicology. vol. 165, n° 0166-445X, pp. 160-171, 26/10/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CESAM, CNRS
Divergent biophysical controls of aquatic CO2 and CH4 in the World's two largest rivers
Carbon emissions to the atmosphere from inland waters are globally significant and mainly occur at tropical latitudes. However, processes controlling the intensity of CO2 and CH4 emissions from tropical inland waters remain poorly understood. Here, we report a data-set of concurrent measurements of the partial pressure of CO2 (pCO2) and dissolved CH4 concentrations in the Amazon (n = 136) and the Congo (n = 280) Rivers. The pCO2 values in the Amazon mainstem were significantly higher than in the Congo, contrasting with CH4 concentrations that were higher in the Congo than in the Amazon. Large-scale patterns in pCO2 across different lowland tropical basins can be apprehended with a relatively simple statistical model related to the extent of wetlands within the basin, showing that, in addition to non-flooded vegetation, wetlands also contribute to CO2 in river channels. On the other hand, dynamics of dissolved CH4 in river channels are less straightforward to predict and are related to the way hydrology modulates the connectivity between wetlands and river channels.
(Scientific Reports. vol. 5, pp. 15614, 26/10/2026)
ULiège, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, KU Leuven, UENF
Polychlorinated biphenyl exposure and corticosterone levels in seven polar seabird species
The role of polychlorinated biphenyls (PCBs) on exposure-related endocrine effects has been poorly investigated in wild birds. This is the case for stress hormones including corticosterone (CORT). Some studies have suggested that environmental exposure to PCBs and altered CORT secretion might be associated. Here we investigated the relationships between blood PCB concentrations and circulating CORT levels in seven free-ranging polar seabird species occupying different trophic positions, and hence covering a wide range of PCB exposure. Blood P7PCB concentrations (range: 61e115,632 ng/g lw) were positively associated to baseline or stress-induced CORT levels in three species and negatively associated to stress-induced CORT levels in one species. Global analysis suggests that in males, baseline CORT levels generally increase with increasing blood P7PCB concentrations, whereas stress-induced CORT levels decrease when reaching high blood P7PCB concentrations. This study suggests that the nature of the PCB-CORT relationships may depend on the level of PCB exposure.
(Environmental Pollution (1970). vol. 197, n° 0013-9327, pp. 173-180, 26/10/2026)
CEBC, INRA, ULR, CNRS, NINA, NINA, NINA, NILU, TOXEN, UQAM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UC