Estimating plastic export from estuaries into the sea using an estuarine-mass-balance model
Estuaries act as an interface between rivers and the sea, and therefore play a key role in transporting plastic to the sea. However, plastic transport in estuaries is complex and estuary-to-sea export is still very uncertain. This study presents a macroplastic mass-balance model that can be applied to specific estuaries, and produces export estimates similar to previous studies. The daily plastic export from estuary to sea during the wet season was estimated to be 290 kg for the Rhine-Meuse Estuary (RME), and 19,431 kg for the Saigon Estuary, where the discharge into the sea is 3.5 times larger for the RME, compared to the Saigon Estuary. Due to limited river discharge measurements for the Saigon Estuary, a yearly simulation could only be performed for the RME, corresponding to an export of 13,300 kg. These estimates fall within the uncertainty range of previous studies. Deposition and remobilization from riverbanks resulted in the largest model fluxes, with magnitudes of 20 t/d for the RME and 430 t/d for the Saigon Estuary. At the same time, the model is most sensitive to the uncertainty in parameters related to deposition. Our results demonstrate that with the right measurements, making reliable estimates of estuary-to-sea export is possible. However, uncertainty in plastic transport processes, like deposition and remobilization, leads to poorly constrained parameters and increased overall model uncertainty. Automated sensors, targeted field experiments, and improved model structure can enhance export estimates and further improve understanding of plastic dynamics in estuaries.
(Marine Pollution Bulletin. vol. 230, n° 0025-326X, pp. 119793, 01/09/2026)
WUR, IGE, IRD, INSU - CNRS, CNRS, INRAE, Fédération OSUG, UGA, Grenoble INP, UGA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Chronic exposure to sodium fluoride or to tebuconazole disrupts the thyroid hormone and immune systems during early development of rainbow trout (Oncorhynchus mykiss)
Over the past 20 years, there has been a growing interest in endocrine-disrupting chemicals (EDCs) found in both terrestrial and aquatic environments. These substances have garnered attention from scientists, the public and regulatory bodies, with many being classified as substances of very high health concern. Only recently, disruption of the thyroid hormone system (THS) by EDCs has also attracted significant attention: In vertebrates, the THS interacts with various physiological systems, including the immune system (IS), and plays a crucial role in development. It can also influence the microbial diversity in certain tissues. The main objective of this study was to investigate the potential impact of sodium fluoride (NaF) on the THS and IS in rainbow trout ( Oncorhynchus mykiss ), a species of both economic and environmental importance. For this end, trout were exposed from the embryonic stage (48 h post-fertilisation) to the juvenile stage for 7 months. Fish were subjected to 1.5 mg F-/L or 5 mg F-/L and 20 µg/L tebuconazole (TBZ; positive control) monitored daily and sampled after 3 and 7 months of exposure to assess potential disruption to the thyroid hormone and immune systems. Results document that chronic exposure to NaF or TBZ during early life stages of rainbow trout induces a broad range of sublethal effects, including physiological condition, immune competence, endocrine regulation and organ morphology. Although mortality was reduced, most probably due to the antifungal activity of TBZ, the consistent alterations observed in thyroid hormone dynamics and immune parameters clearly indicate a deterioration of overall health.
(Aquatic Toxicology. vol. 297, n° 0166-445X, pp. 107867, 01/08/2026)
VIMEP, ANSES, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ANSES, VU, COS, UB
Evaluating migration hazard for recently remobilized managed coastal dunes
Sparsely vegetated or unvegetated coastal dunes are inherently dynamic, regardless of their size (Hesp et al., 2022). A salient characteristic of these dunes is their landward migration, driven by prevailing onshore winds, at rates that can exceed several meters per year. The rapid evolution of freely evolving coastal dunes inevitably raises concerns about the burial of infrastructure and more generally, the back dune areas. In a context where dune system remobilization is emerging as a nature-based management solution with multiple benefits (ecological reconnection, chronic marine erosion and sea-level rise effects mitigation), precise, spatially explicit quantitative assessments of dune migration hazards are essential. This is more critical given the trends of increasing urbanization and the concentration of socio-economic interests in coastal zones. Along the 230 km of the Aquitaine coast (southwest France), coastal dunes, which landscape is largely inherited from nearly two centuries of management, stabilization, and episodic mechanical re-profiling, have undergone spontaneous remobilization over the past decade (Nicolae Lerma et al., accepted). Across extensive sectors, dunes have transitioned from geometrically fixed, vegetated forms to aerodynamic, transgressive dunes (Figure 1a). This shift presents both opportunities and challenges for short- and long-term management strategies but also raises critical questions about accommodating rapid migration rates and evolving dune morphology. Current approaches to assessing burial hazards often overlook key parameters, such as interannual wind variability, climate change-induced trends in forcing, dune and back-dune morphology, and sediment budgets. Furthermore, methods relying on historical migration rates are inapplicable in regions where dunes were artificially stabilized during the 20th century through management interventions. Using annual airborne LiDAR data (Figure 1b.) and simulations with the morphodynamic model DUNA (Kombiadou et al., 2023, Figure 1c.), we analyze the factors influencing the migration speed of recently unvegetated dunes. We also investigate the impact of hybrid management strategies (designed to either accelerate or mitigate dune remobilization) at large spatial scales (hundreds of meters to tens of kilometers).
(13/07/2026)
BRGM, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ONF
Effect of the microparasite Perkinsus olseni on the bioturbation activity and engineering potential of the Manila clam Ruditapes philippinarum
Host behavioral modifications induced by parasites can have profound ecological consequences, especially when they affect ecosystem engineers such as bioturbators. While the influence of macroparasites on host behavior and, by extension, on ecosystem functioning is documented in the marine realm, the role of microparasites remains unexplored. The association between Perkinsus olseni, a widespread microeukaryotic parasite, and the Manila clam Ruditapes philippinarum, an abundant bioturbator in many coastal soft-bottom environments, is an interesting model for investigating this overlooked aspect. Infection by P. olseni has been shown to alter various physiological parameters in clams, such as immune response, metabolic activity, and reproductive performance. However, whether these internal disruptions translate into behavioral changes, such as modifications in sediment particle transports initiated by clams, remains an open question. In this study, we explore whether infection by P. olseni influences the bioturbation activity of the Manila clam, a process with significant implications for ecosystem processes, such as nutrient fluxes, in coastal environments. We did not report major changes in the engineering potential of the Manila clam when infected with non-lethal doses of Perkinsus olseni. However, we noticed a subtle increase in the magnitude of sediment transport activities, which may reflect behavioral adaptations. Given the ecological role of R. philippinarum as a driver of benthic processes, even little parasiteinduced behavioral shifts could cascade down to affect ecosystem processes such as sediment dynamics and benthic community structure. Exploring such interactions opens new perspectives on how microparasites may influence ecosystem functioning, not only through physiological disturbances but also via changes in host functional traits.
(Journal of Invertebrate Pathology. vol. 217, n° 0022-2011, pp. 108605, 01/07/2026)
ECOMAP, AD2M, SU, CNRS, SBR, SU, CNRS, EDYMAR, AD2M, SU, CNRS, SBR, SU, CNRS, AD2M, SU, CNRS, SBR, SU, CNRS, SBR, SU, CNRS, CNRS, STAMAR, INSU - CNRS, SU, CNRS, ISTerre, IRD, INSU - CNRS, USMB [Université de Savoie] [Université de Chambéry], CNRS, Fédération OSUG, UGA, FR2424, SBR, SU, CNRS, UB, Bordeaux INP, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CENAREST
Continuous speleothem record from central Tunisia (the Mine cave) reveals climatic events for the last 27 ka
The Last Deglaciation, a key period punctuated by many climatic events, has been recorded in several natural archives but, it has been rarely recorded continuously on speleothems because of the presence of stops in their growth rate due to cold/dry climates. Here we present the results of a stalagmite (Min-stm2) from the Mine Cave (Oueslatia, Tunisia) that cover continuously the last 27 ka BP after a very slow growth between 120 ka to 35 ka. The time resolution, calculated with twenty-eight U/Th dating points and a 1 mm sampling space for stable isotopes, reaches 24 years during the Bølling-Allerød (BA) period, while it was the lowest (330 a/mm) during the Younger Dryas (YD). The growth rate (GR) curve reveals a sudden growth increase at 27.5 ± 0.08 ka BP, a key point in the stalagmite history, demonstrating that infiltration due to a humid and a relatively temperate climate started again at least in Tunisia. More vigorous northwesterly winds combined with the southern displacement of the ITCZ belt may explain this abrupt hydrological change. Despite of extreme cold climate that occurred N-Mediterranean area (i.e. Western Europe) during the Last Glacial Maximum (LGM) and the Oldest Dryas, the studied stalagmite kept a sustained GR showing a quite high humidity in the N-Tunisia area. The Last Deglaciation is here clearly marked by a large decrease in the calcite δ18O and δ13C between maximum values at 21.9 ka, denoting the coldest conditions, and minimum values at 8.5 ka coinciding with the warmest conditions. Even if the isotopic curves nicely mimic the ice and marine core records of the deglaciation, detailed events show some noticeable differences. For example, the stalagmite δ13C at the end of the BA is interrupted by a rapid and pronounced isotopic increase denoting colder conditions after 13.3 ± 0.1 ka BP which could be related to the IACP (Intra Allerød Cold Period). GR during the YD appears extremely slow. The Holocene onset, at about 11.7 ± 0.09 a BP, is marked by a gradual decrease in δ18O and δ13C until 8.3 ka associated with high GR suggesting increased precipitation. Despite the high time resolution during this period (better than 40 years), the 8.2 ka event is not recorded, marking a different sensitivity compared with more western and northern speleothem records. While the δ18O continuously increased after the Holocene optimum at 8.3 ka, a positive excursion occurred on the δ13C between 8.3 ka and 6.3 ka suggesting a reduction in the vegetation activity. This is likely due to increased seasonality with drier spring/summer conditions and humid autumn/winter and/or lower CO2 dissolution in the soil water during infiltration. The comparison with a former studied stalagmite from the same cave brings precious information about the local influences in recording detailed climatic variations.
(Quaternary Science Reviews. vol. 384, n° 0277-3791, pp. 109921, 01/07/2026)
LMRE, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, UTM, PALEOCEAN, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, IGEC, Xjtu, M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, UNIROUEN, NU, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
PFAS Data Hub: An open data portal featuring geovisualisation
Per-and polyluoroalkylated substances (PFAS) are a group of man-made chemical substances used in everyday products and industry processes since the 1950s. They contain carbon-fluorine bonds, among the strongest in chemistry, resulting in intrinsic or indirect extreme environmental persistence and earning them the nickname "forever chemicals". In a context of growing awareness of PFAS toxicity and widespread pollution, the Forever Pollution Project (FPP), a cross-border journalistic investigation, compiled data on measured and estimated PFAS contamination across Europe, published as an interactive map. In this data paper we present the PFAS Data Hub (PDH), a project building upon the FPP dataset and reprocessing it using a more robust and transparent methodology. We incorporated several additional data sources, most of which are automatically updated on a monthly basis. To our knowledge, this constitutes the only compilation of PFAS contamination data at the European scale. It is intended to support research projects across a wide range of different disciplines, and to be used as a source of information by journalists, citizens and civil society organisations. The data, as well as a geovisualisation tool with filtering and export options, is available on the PDH website: https://pdh.cnrs.fr.
(03/06/2026)
LIS, AMU, UTLN, CNRS, PRODIG (UMR_8586 / UMR_D_215 / UM_115), UP1, IRD, SU, CNRS, UPCité, IRISSO, PSL, CNRS, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Molecular detection reveals infection phenology of a host – Trematode system (Cerastoderma edule – Bucephalus minimus) in southwestern France
Accurate detection of parasites in their hosts is essential for pathogen control and ecosystem studies. The trematode Bucephalus minimus (Digenea: Bucephalidae) infects the edible cockle Cerastoderma edule, a commercially fished and ecologically important bivalve that serves as its first intermediate host, in which it can be difficult to detect. We investigated detection accuracy and infection phenology of this host-parasite system in Arcachon Bay, France. Cockles were collected monthly over one year to compare detection methods: stereomicroscopy of tissues versus molecular detection by quantitative PCR (qPCR) and digital PCR (dPCR). Visual detection reported 30% prevalence, qPCR 36%, and dPCR 50%, the most sensitive method. Seasonal cockle sampling and cohort analysis enabled tracking of the 2021 cohort over two years (Sep 2022 – Jun 2024) using both visual and molecular detection. With both approaches, first infection appeared when the cohort reached 14 mm shell length in fall 2022, most likely coinciding with sexual maturity. Molecular detection consistently revealed higher prevalence and greater temporal variation than visual detection, allowing for the first description of an infection phenology in this system. Prevalence sharply rose in spring 2023, was highest in summer, declined in fall, and increased again in spring 2024 to a lesser extent. These fluctuations appear linked to cockle size and maturity, as well as to the migration pattern of the definitive host (Dicentrarchus labrax), both influencing parasite transmission. Our results highlight the importance of using sensitive molecular methods to accurately assess parasite prevalence and understand transmission dynamics, essential for monitoring parasite and host populations.
(Journal of Invertebrate Pathology. vol. 216, n° 0022-2011, pp. 108570, 01/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMS POREA, INSU - CNRS, CNRS, INRAE, ECOMAP, AD2M, SU, CNRS, SBR, SU, CNRS, SBR, SU, CNRS
Adverse effects of sodium fluoride exposure on the development, thyroid morphology and disease resistance in rainbow trout (Oncorhynchus mykiss) embryos and larvae
Endocrine disruptors, ubiquitous in terrestrial and aquatic environments, have come under increased public and scientific scrutiny and are classified as substances of great concern for human health and the environment. The main objective of which is to determine the potential role of sodium fluoride (NaF) on rainbow trout health, with a particular interest in the thyroid hormone system, the immune system, and the development and behavior in early life stages. Rainbow trout ( Oncorhynchus mykiss ) embryos (265DD) were exposed for 15 days to NaF at 0, 0.5, 1, 5, 8 and 15 mg/L of F-. After the first 15 day-exposure, larvae were divided into three batches (1) exposed to NaF for further 8 days at the same concentrations, (2) infected with the Infectious Hematopoietic Necrosis virus, or (3) held in clean water. Fish were monitored daily to follow their development, morphology and behavior and sampled after 15 or 23 days of exposure, with and without viral infection, to evaluate effects on the THS (eye development, thyroid) and their capacity of resistance to IHNV. Results show impaired growth (decrease in size and an increase in the rate of abnormalities rate) and significative behavior impact at 15 mg/L of F- with a decrease of activity (speed, and light stress reaction). 5 mg/L of F- caused delayed hatching, a decrease in virus-related mortality, an increase of thyroid follicles number, and increased photoreceptor layer thickness. Further analyses will determine the immunotoxicity of this potential ED by analyzing gene activity and blood parameters in older fish.
(Aquatic Toxicology. vol. 295, n° 0166-445X, pp. 107815, 01/06/2026)
VIMEP, ANSES, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, VU, UB, ANSES
Valorisez les résultats de vos recherches via Peer Community In Ecotoxicology and Environmental Chemistry
Les Peer Community In… sont un processus éditorial de science ouverte. Il s'agit de communautés spécialisées effectuant une évaluation scientifique par les pairs et à la demande des auteurs, de preprints déposés sur des serveurs appropriés. Dans chaque PCI, les recommandeurs, gèrent une évaluation détaillée de l’article. S’ensuit une décision éditoriale qui mène soit au rejet, soit à la demande de corrections, soit à la validation de l’article. Dans ce dernier cas, le recommandeur écrit un texte de recommandation dans lequel il explique pourquoi il a validé l’article. L’ensemble de la communauté scientifique a accès gratuitement au contenu validé du preprint et aux évaluations/recommandations sur le site du PCI. Les PCIs peuvent également publier les preprints recommandés dans PCI Journal, mais les auteurs peuvent éventuellement le soumettre pour publication dans une revue scientifique de leur choix, notamment dans les revues qui se sont déclarées PCI-friendly. Peer Community in Ecotoxicology and Environmental Chemistry fait partie des 21 PCI existant à ce jour. Les articles rentrant dans le champ de PCI Ecotox Env Chem concernent des travaux originaux (observations, expérimentations, modélisations, approches théoriques…) qui permettent des avancées significatives de la connaissance dans les champs de l'écotoxicologie terrestre et aquatique, ainsi que de la chimie de l'environnement. PCI Ecotox Env Chem considère la dynamique et le transport des composés chimiques dans l'environnement, leur transfert vers les organismes au sein des réseaux trophiques, et leurs effets à différents niveaux d'organisation biologique et géographique. Ainsi, PCI Ecotox Env Chem intègre différentes disciplines et approches qui répondent aux problématiques d'écotoxicologie et de toxicologie de l'environnement : chimie analytique, physiologie, microbiologie, génétique, génomique, ingénierie environnementale, modélisation, science des données, évaluation des risques… PCI Ecotox Env Chem dispose à ce jour d'un panel international de 25 recommandeurs, et développe son partenariat avec les réseaux scientifiques et sociétés savantes, ainsi qu'avec des journaux partenaires.
(27/05/2026)
ECOSYS, INRAE, LPTC, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, INRS, SEBIO, INERIS, URCA, ULH, NU, URCA, CNRS
A multi-proxy sediment record of atmospheric contaminant deposition in the Paris Basin since the nineteenth century
Small ponds represent valuable but still underexploited archives for reconstructing long-term environmental contamination, particularly those disconnected to fluvial networks. In this study, a sediment core from the Saint-Denis pond (Paris Basin, France) was used to reconstruct the historical evolution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and per- and polyfluoroalkyl substances (PFAS) over the last 150 years. The 137Cs record, characterized to the well-defined atmospheric fallout peak in 1963, was retained as the most robust age model, particularly for the second half of 20th century, when investigated contaminant dynamics were strongly influenced by human activities. The resulting chronology indicates continuous sediment accumulation from the late 19th century to 2021.Temporal trends in PAHs, PCBs, and PFAS closely match known historical production, use, and regulatory phases, providing independent validation of the 137Cs-based age model. Although indirect contaminant transfers via surrounding forest soils cannot be entirely excluded, the sediment record predominantly reflects atmospheric-driven contamination. This multi-proxy approach demonstrates the relevance of pond sediments for environmental monitoring and retrospective assessment of long-term contamination trends at the regional scale.
(Environmental Monitoring and Assessment. vol. 198, n° 0167-6369, pp. 625, 21/05/2026)
METIS, EPHE, PSL, INSU - CNRS, SU, CNRS, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, iSTeP, INSU - CNRS, SU, CNRS, CY, GéHCO, UT, GEDI, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA