Gamma irradiation-induced offspring masculinization is associated with epigenetic changes in female zebrafish
Sex ratio variation is a key topic in ecology, because of its direct effects on population dynamics and thus, on animal conservation strategies. Among factors affecting sex ratio, types of sex determination systems have a central role, since some species could have a sex determined by genetic factors, environmental factors or a mix of those two. Yet, most studies on the factors affecting sex determination have focused on temperature or endocrinedisrupting chemicals (EDCs), and much less is known regarding other factors. Exposure to gamma irradiation was found to trigger offspring masculinization in zebrafish. Here we aimed at deciphering the potential mechanisms involved, by focusing on stress (i.e. cortisol) and epigenetic regulation of key genes involved in sex differentiation in fish. Cortisol levels in exposed and control (F0) zebrafish females' gonads were similar. However, irradiation increased the DNA methylation level of foxl2a and cyp19a1a in females of the F0 and F1 generation, respectively, while no effects were detected in testis. Overall, our results suggest that parental exposure could alter offspring sex ratio, at least in part by inducing methylation changes in ovaries.
(Ecotoxicology and Environmental Safety. vol. 269, n° 0147-6513, pp. 115790, 01/01/2024)
IRSN/PSE-ENV/SERPEN/LECO, IRSN/PSE-ENV/SERPEN, IRSN, UMR MARBEC, IRD, IFREMER, CNRS, UM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Expertise préalable à la création d’un tableau de maladie professionnelle ou à l’élaboration de recommandations aux comités régionaux de reconnaissance des maladies professionnelles - Expertise sur les tableaux de maladies professionnelles existants nécessitant une mise à jour
La commission chargée d'évaluer le coût de la sous-déclaration des accidents du travail et des maladies professionnelles pour la branche maladie instituée par l’article L. 176-2 du code de la Sécurité Sociale (CSS), a régulièrement souligné que la non-reconnaissance de certaines maladies professionnelles pouvait être due notamment « à l’obsolescence de certains tableaux de maladies professionnelles qui n’intègrent pas l’état des connaissances scientifiques et épidémiologiques, et, d’autre part, à la limitation des pathologies qu’ils peuvent prendre en compte pour ce qui est des durées d’exposition et des produits et substances prévus ». Le dernier rapport issu des travaux de la commission sur la sous-déclaration des AT-MP, remis au Parlement en juillet 2021 (Commission sur la sous-déclaration des accidents du travail et des maladies professionnelles 2021), mettait ainsi en avant le caractère inadapté ou incomplet de certains tableaux de maladies professionnelles (TMP), s’agissant notamment de la désignation de la maladie ou des travaux associés. Compte tenu des évolutions des connaissances relatives aux modalités diagnostiques des maladies indiquées dans les TMP mais aussi aux travaux en lien avec ces maladies, la Direction générale du travail, la Direction de la Sécurité sociale et le Secrétariat général du ministère de l’agriculture et de la souveraineté alimentaire ont saisi l’Anses le 16 mars 2023 pour réaliser un travail d’expertise visant à étudier d’une part l’opportunité scientifique et médicale d’actualiser les différents tableaux, et d’autre part de disposer, pour chaque tableau, des raisons justifiant ou non une évolution des conditions d’accès à ces tableaux.
(pp. 113 p., 01/01/2024)
Irset, UA, UR, EHESP, INSERM, Biosit : Biologie - Santé - Innovation Technologique, IRIS, EHESS, INSERM, CNRS, UJML, UMRESTTE UMR_T9405, UCBL, INED, UBO UFR MSS EUMB, UBO EPE, CHRU Brest, CESP, UVSQ, AP-HP, INSERM, UB, EPICENE, BPH, UB, INSERM, NU, IRISSO, PSL, CNRS, INRAE, CONSTANCES, UVSQ, INSERM, UPCité, INSERM, LABERS, UBS, UBO EPE, IBSHS, UBO EPE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, DER, ANSES, DiSSES, ANSES
Reactivity and fluxes of antimony in a macrotidal estuarine salinity gradient: Insights from single and triple quadrupole ICP-MS performances
Trace element analyses in brackish waters are challenging for many elements at ppb/ppt levels and analytical methods. In this work, we compare two methods using inductively coupled plasma mass spectrometry (ICP-MS) for quantifying antimony (Sb). Results of a previous study along the salinity gradient in a macrotidal estuary (i.e., the Gironde Estuary, France) using isotopic dilution via single quadrupole ICP-MS are compared to reanalyzed aliquots of the same samples. Direct analyses of estuarine water samples via standard additions (N = 52) were performed with a QQQ-ICP-MS (new generation, iCAP TQ Thermo®) to determine dissolved (< 0.2 µm filtered and UV-irradiated replicates) Sb concentrations during two contrasting hydrological conditions (low vs high freshwater discharges). Despite following good analytical practices on both studies, the use of the new analytical device provides more robust results and highlighted a characteristic 121Sb isotopic interference in estuarine samples at S > 20, efficiently eliminated by the QQQ-ICP-MS performance. This means that Sb reactivity shows an additive, non-conservative behavior in the Gironde Estuary, with a more defined bell-shaped profile in low discharge compared to high discharge conditions. This approach allows to quantify for the first time in the literature Sb dissolved net fluxes from the Gironde Estuary to the Atlantic coast and provides an updated value for the seawater endmember. This study opens future applications of QQQ-ICP-MS for quantifying on a more routine basis dissolved trace elements in brackish waters, providing guidelines and good practices for field studies regarding Sb determination in estuarine systems.
(Marine Chemistry. vol. 267, n° 0304-4203, pp. 104465, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, KIT
Gestion quantitative de l’eau et usages agricoles sous contrainte climatique
Plus grande région agricole de France et d’Europe, la Nouvelle-Aquitaine subit comme l’ensemble du territoire national, les conséquences du changement climatique et notamment des sécheresses. L’eau et son accès sont des enjeux cruciaux pour une partie des agriculteurs mais une part de la population est inquiète des possibles conséquences environnementales. La question de la gestion de l’eau est donc au cœur de controverses publiques depuis quelques années. C’est dans ce contexte qu’ AcclimaTerra s’est proposé d’apporter une contribution au débat dans le but de réintroduire des données et des résultats scientifiques sur la ressource en eau.
(pp. 68, 23/02/2026)
BRGM, Bordeaux Sciences Agro, CED, IEP Bordeaux, UB, CNRS, AGIR, Toulouse INP, Comue de Toulouse, INP - PURPAN, Toulouse INP, Comue de Toulouse, INRAE, UMR G-EAU, Cirad, BRGM, IRD, INRAE, Institut Agro, UP, HydrASA, IC2MP [Poitiers], UP, INC-CNRS, CNRS, UMR EGFV, UB, Bordeaux Sciences Agro, INRAE, UFC, UBFC, UP, Solagro, ISVV, UB, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Five new species of Terebellides (Annelida, Polychaeta, Trichobranchidae) from Papua New Guinea (Bismarck and Solomon seas)
Five new species of Terebellides are described from coastal and deep waters of Papua New Guinea, using both morphology and molecular tools (for four species). Terebellides elenae n. sp. is characterized by the absence of both a glandular lateral region on TC3 and papillae on margins of the branchial lamellae and by the presence of partially fused branchial lobes with conspicuous fifth lobe and dorsal rounded projections until TC6. Terebellides fauchaldi n. sp. has a very large glandular lateral region on the third thoracic chaetiger (TC3), a fifth branchial lobe and partially fused branchial lobes, and conspicuous dorsal rounded projections on TC2–6. Terebellides madeep n. sp. is characterized by a thin glandular region on TC3 and by four free branchial lobes. Terebellides oculata n. sp. is one of the only two species in the world to have eyespots. Finally, T. papillosa n. sp. has geniculate chaetae on TC6 and TC7 and bears a large number of papillae. A majority-rule consensus tree using the 16S gene and an identification key for all Terebellides species described from the Central Indo-Pacific region are provided.
(Frontiers in Ecology and Evolution. vol. 12, n° 2296-701X, pp. 1349362, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, USP, UMS POREA, INSU - CNRS, CNRS, INRAE
Impacts of AMOC Collapse on Monsoon Rainfall: A Multi-Model Comparison
A collapse of the Atlantic Meridional Overturning Circulation (AMOC) would have substantial impacts on global precipitation patterns, especially in the vulnerable tropical monsoon regions. We assess these impacts in experiments that apply the same freshwater hosing to four state-of-the-art climate models with bistable AMOC. As opposed to previous results, we find that the spatial and seasonal patterns of precipitation change are remarkably consistent across models. We focus on the South American Monsoon (SAM), the West African Monsoon (WAM), the Indian Summer Monsoon (ISM) and the East Asian Summer Monsoon (EASM). Models consistently suggest substantial disruptions for WAM, ISM, and EASM with shorter wet and longer dry seasons (−29.07%, −18.76%, and −3.78% ensemble mean annual rainfall change, respectively). Models also agree on changes for the SAM, suggesting rainfall increases overall, in contrast to previous studies. These are more pronounced in the southern Amazon (+43.79%), accompanied by decreasing dry-season length. Consistently across models, our results suggest a robust and major rearranging of all tropical monsoon systems in response to an AMOC collapse.
(Earth's Future. vol. 12, n° 2328-4277, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
A critical review of pollution active biomonitoring using sentinel fish: Challenges and opportunities
Water pollution is a significant threat to aquatic ecosystems. Various methods of monitoring, such as in situ approaches, are currently available to assess its impact. In this paper we examine the use of fish in active biomonitoring to study contamination and toxicity of surface waters. We analysed 148 previous studies conducted between 2005 and 2022, including both marine and freshwater environments, focusing on the characteristics of the organisms used as well as the principal goals of these studies. The main conclusions we drew are that a wide range of protocols and organisms have been used but there is no standardised method for assessing the quality of aquatic ecosystems on a more global scale. Additionally, the most commonly used developmental stages have been juveniles and adults. At these stages, the most frequently used species were the fathead minnow (Pimephales promelas) and two salmonids: rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta). Few studies used earlier stages of development (embryos or larvae), mostly due to the difficulty of obtaining fish embryos and caging them in the field. Finally, we identified research gaps in active biomonitoring for water quality assessment which could indicate useful directions for future research and development.
(Environmental Pollution. vol. 360, n° 0269-7491, pp. 124661, 23/02/2026)
UR EABX, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, RiverLy, INRAE
Trophic transfer effects of PS nanoplastics and field-derived nanoplastics in the freshwater clam Corbicula fluminea
Plastic pollution is of global concern. Many studies investigated the effect of micro and nanoplatics towards aquatic organisms. However, relatively few studies were assessed on freshwater organisms. Another aspect of this pollution is the impact of trophic transfer on plastic distribution and on food chain in order to evaluate its potential risk towards environmental and human health. In this context, the objective of this study was to assess the ecotoxicological impacts of different types of nanoplastics (NPs) on freshwater organisms exposed through trophic transfer. Freshwater microalgae Scenedesmus subspicatus were contaminated for 48 h with realistic concentrations of NPs (0.008, 10 and 100 mu g/L). Two types of NPs were tested: commercial PS NPs and NPs generated from macro-sized plastics collected in the field (ENV NPs). Freshwater Corbicula fluminea bivalves were then fed with the contaminated algae every 48 h for 21 days. Results showed that trophic exposure led to the induction of oxidative stress (CAT activity). Overall, NPs trophic exposure caused downregulations of genes implicated in many cellular processes (immunity, oxidative stress, neurotoxicity, endocytosis, apoptosis). This present study allowed to demonstrate the relevance of investigating the trophic transfer effects of NPs on a freshwater trophic chain. Further studies should focus more on larger levels of the food chain.
(Aquatic Toxicology. vol. 277, n° 0166-445X, pp. 107160, 23/02/2026)
BIOSSE, UCO, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMS POREA, INSU - CNRS, CNRS, INRAE, GR, UR, INSU - CNRS, CNRS, ULaval, IPG Paris
Impact du barrage de l’usine marémotrice sur la sédimentation dans l’estuaire de la Rance
Rejoignant la Manche entre Dinard et Saint-Malo, les caractéristiques naturelles de l'estuaire de la Rance combinées à une amplitude de marée remarquable, jusqu'à 13,6 mètres en vive-eau, ont permis la mise en service en 1967 de la première usine marémotrice au monde. L'exploitation de l'usine induit des modifications du régime hydrologique à même de modifier la dynamique sédimentaire dans l'estuaire de la Rance. A l'initiative de l'EPTB Rance Frémur Baie de Beaussais, une étude a été menée pour y déterminer les taux d’accumulation sédimentaire à l’échelle de temps pluri-décennale au moyen du 210Pb (T1/2 = 22.3 ans) et du 137Cs (T1/2 = 30.08 ans). Une campagne de carottage, réalisée en mars 2022, a permis de prélever 19 carottes sédimentaires, réparties entre l’écluse du Chatelier au sud et le barrage au nord. Au laboratoire, toutes les carottes ont été ouvertes longitudinalement, photographiées, radiographiées puis échantillonnées en vue de la détermination de la teneur en eau, de la granulométrie et des radioéléments d’intérêt. Aux sites proches des rives ou dans des anses, les profils de 210Pbxs montrent souvent deux pentes dans l’évolution avec la profondeur de cet élément, dont la séparation se situe au niveau des couches où le maximum de 137Cs, attribué aux retombées des essais nucléaires (1963), est observé. Dans ce cas, les taux de sédimentation des couches les plus récentes sont supérieurs, d’un facteur 2 à 3, à ceux calculés pour les sédiments « pré-barrage ». Les résultats suggèrent qu’il y a eu une augmentation de la sédimentation dans les secteurs central et amont de l’estuaire de la Rance depuis la mise en service du barrage.
(Revue Paralia, n° 1760-8716, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UB
Factors Controlling Mud Floc Settling Velocity in a Highly Turbid Macrotidal Fluvial‐Estuarine System
This study assesses the settling dynamics of suspended sediments along the hyper‐turbid Gironde Garonne fluvial‐estuarine system, with an innovative optical SCAF instrument (System of Characterization of Aggregates and Flocs). Two fields campaigns were carried out to determine the settling velocity and properties of suspended sediments during a semi‐diurnal tidal cycle, as well as hydrodynamic conditions and water properties. The two sampling stations were representative of two regions: a tidal river dominated by fresh water and an estuary affected by salty or brackish waters. A high spatial variability of the settling velocity was observed along the fluvial‐estuarine system and vertically along the water column. Settling velocities ranged from 0.02 to 0.4 mm/s. This study confirms that in hyper‐turbid systems, the suspended sediment concentration (SSC) is predominantly driving the settling dynamics of suspended sediment. Threshold concentrations have been defined for the flocculation and hindered regimes where the settling velocity may vary by one order of magnitude. Although in natural environments it is difficult to distinguish between the effects of SSC and turbulence (as they are correlated), in the Gironde‐Garonne system the turbulent shear G seems to affect the settling of suspended sediment to a lower extent. Settling velocity variations cannot be directly correlated to salinity or organic matter content. Despite differences in hydrodynamic and environmental conditions in fluvial and estuarine regions, a common prediction law has been found to estimate settling velocity of suspended sediment as a function of suspended sediment concentration.
(Journal of Geophysical Research. Oceans. vol. 129, n° 2169-9275, pp. e2024JC021558, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, RHITME, Cerema, IGE, IRD, INSU - CNRS, CNRS, INRAE, Fédération OSUG, UGA, Grenoble INP, UGA, Fédération OSUG