Temperature and hydrological variations during the late-glacial in the Central Mediterranean: Application of the novel ostracod-clumped isotope thermometer
This study shows, for the first time, the absence of a vital effect in the clumped isotope carbonate (Δ47) fossil ostracod signal and confirms the ability of the novel ostracod-Δ47 thermometer to reconstruct past temperatures and hydrological conditions in complex lacustrine systems. Furthermore, the application of Δ47 analyses on the ostracod species Candona angulata and Cyprideis torosa from Lake Trasimeno record (central Italy), which today precipitate their shells during the cold and the warm season respectively provides evidence that by combining biological (i.e., ostracod shell precipitation timing), paleontological (i.e., identification of ostracod species) and geochemical (i.e., Δ47) approaches, the ostracod-Δ47 thermometer accurately reconstructs past seasonality. Despite the absence of a vital effect, not all species can be combined for Δ47 analyses in environments with seasonal temperature variations; only those that precipitate their shells during the same season should be considered. The application of the ostracod-Δ47 thermometer on the Trasimeno lacustrine record gives rise to the first continental warm season paleotemperature reconstruction of the last 43 ky in central Mediterranean area. The combination of Δ47 and oxygen isotope composition (δ18Oost) measured on ostracod shells provides the isotopic composition of the water from which the carbonate precipitated (δ18Ow) and thereby, changes in the evaporation/precipitation balance in this area. Before the Last Glacial Maximum (LGM), equivalent to the Marine Isotopic Stage 3 (MIS3, from 43 to 29ky), warm season temperatures ranged from 15 ± 1.6 °C to 22 ± 2.3 °C, equivalent to 2 to 6 °C colder than today. Hydrological conditions during this period are similar to the present-day ones, characterized by a permanent lake and a high evaporation/precipitation ratio (E/P). The drastic decrease of the warm season temperatures (ranging from 10 ± 2.9 °C to 17 ± 3.1 °C) and of the E/P ratio during LGM and Late-glacial (MIS2, from 29 to 11.6 ky) correspond to the global climate cooling and low summer insolation, suggesting an amplifying role, of the latter, in the effects of the millennial scale climatic variations. At the Pleistocene/Holocene transition, both warm season temperature (25 ± 2 °C) and the E/P ratio increased in conjunction with the summer insolation. During the early Holocene, warm season temperature (23 ± 2 °C) closely resembles present-day values. However, cold season temperature (12 ± 2 °C) is approximately 4 °CC warmer than today. Notably, no hydrological differences are identified between the warm and the cold season underlying a lower seasonality contrast compared to the present, along with enhanced warm season precipitation. The good agreement between the Δ47 temperatures reconstructed for the last 1 ky and the temperatures presently recorded at Lake Trasimeno (8 °C cold and 22 °C for warm season), confirms the accuracy of the analyses and the applicability of the ostracod-Δ47 thermometer to reconstruct seasonal temperature changes.
(Earth and Planetary Science Letters. vol. 625, n° 0012-821X, pp. 118470, 01/01/2024)
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
Observations of Tide- and Wave-Driven Groundwater Dynamics in Meso-Tidal Sandy Beach
This study focuses on the non-hydrostatic groundwater dynamics of a meso-tidal sandy beach under the influence of tides and waves. A field campaign was conducted at Lacanau Beach, France, during four consecutive tide cycles in March 2022. Groundwater dynamics was monitored based on a network of buried pressure sensors. The data analysis revealed the combined influences of waves and tides on the groundwater circulation. Tidal-scale groundwater flows are predominantly seaward, primarily controlled by the head gradient resulting from a high coastal aquifer. A circulation cell develops under the swash zone and moves across the beachface following the tidal oscillations. On a daily scale per alongshore and vertical units, the observed flow is 2.5 m$^3$ .m$^{-2}$ .day$^{-1}$, i.e., 912.5 m$^3$.m$^{-2}$.year$^{-1}$. Extrapolating the present dataset, it may be expected that combined events, such as drought-induced aquifer depletion with high tides, could lead to beach-scale gradient reversal, potentially causing salinisation of the continental aquifer.
(Water. vol. 16, n° 2073-4441, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, MIO, IRD, AMU, INSU - CNRS, UTLN, CNRS, SIAME, UPPA
Millennial‐Scale Climate Variability Potentially Shaped the Early Interglacial Optimum in Southern Europe
The seasonal and latitudinal distribution of insolation is considered the main factor controlling the magnitude and timing of interglacial periods. However, despite small differences in insolation forcing, vegetation and hydrology in southern Europe during past interglacials are variable and the gradual change in insolation cannot explain the observed short‐lived forest optimum. Here we focus on vegetation and hydroclimatic changes at orbital‐ and suborbital‐scales in southwestern Europe during two past warm interglacial periods with reduced ice‐sheets, namely Marine Isotope Stages (MIS) 9e and 5e. We provide new pollen and sea surface temperatures records for MIS 9e from IODP Site U1385. This pollen record shows a forest expansion in southern Iberia over a 14 ky interval, bracketed by the millennial‐scale cooling events of Termination IV and MIS 9d. Between 334.5 and 332.5 ka, forest expansion reached a maximum, suggesting increased winter moisture during early MIS 9e. Model‐data comparison for MIS 9e and 5e shows that insolation is the main driver of the orbital‐scale vegetation and precipitation changes in Iberia, atmospheric CO2 forcing playing a secondary role. The high‐frequency component of the MIS 9e and 5e forest timeseries highlights the early interglacial forest and precipitation maxima as prominent suborbital events lasting ∼2 ky. We propose that the primarily insolation‐driven forest and precipitation optima were fostered by the non‐equilibrium conditions generated by the millennial‐scale deglacial variability during the early interglacials. Additionally, the early end of these optima may have been favored by a cooling and drying event that is part of the persistent intra‐interglacial variability.
(Paleoceanography and Paleoclimatology. vol. 39, n° 2572-4525, pp. e2024PA004846, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CCMAR, UAlg, IPMA, IDAEA, CSIC
Environmental controls on lifeguard-estimated surf-zone hazards, beach crowds, and resulting life risk at a high-energy sandy beach in southwest France
Understanding and predicting surf zone risks is of paramount importance to prevent drowning incidents and severe spine injuries on beaches globally. This study holistically addressed life risk at La Lette Blanche beach, southwest France, during the lifeguard-patrolled summer period (July-August) 2022, where intense rip currents and shore-break waves co-exist at different times and locations along the beach. Beach crowds and the levels of rip current and shore-break wave hazards were estimated hourly by lifeguards during patrolling hours. Wave, tide and weather conditions were also continuously recorded, providing comprehensive insights into the primary environmental controls on surf zone hazards and beach attendance. Results show that the daily average rip current hazard increases with large, long-period and near shore-normal waves, while the shore-break wave hazard is increased for long-period, near shore-normal waves and large tide ranges. Beachgoer crowd numbers increase on warm, sunny and light wind days although a severe heat wave occurring in July 2022 significantly decreased daily average beach crowd and deeply affected beach use. Days characterized by strong hazards and large beach attendance were associated with the largest amount of lifeguard rescues and drowning incidents, although correlations decreased by the end of the summer. This is hypothesized 1 to be the signature of evolving lifeguard strategies (e.g. preferred locations of the supervised bathing zone, prevention measures) as they progressively increase their understanding of the surf zone hazards variability in both time and space at their beach as a function of tidal stage and incident wave conditions. Warm, sunny and light-wind sunny days (maximizing beach crowds), with large, longperiod shore-normally incident waves and large tide range (maximizing surf zone hazards) were the most risky days, with shore-break waves and rip current hazards notably peaking at different times of the day. This study shows that lifeguards can be a valuable source of data to improve understanding of the environmental controls on beach crowd, surf zone hazards and life risk at the beach, which provides critical information to the development of holistic beach risk predictors.
(Natural Hazards. vol. 120, n° 0921-030X, pp. 1557–1576, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UR ETTIS, INRAE
Concurrent Asian monsoon strengthening and early modern human dispersal to East Asia during the last interglacial
The relationship between initial Homo sapiens dispersal from Africa to East Asia and the orbitally paced evolution of the Asian summer monsoon (ASM)—currently the largest monsoon system—remains underexplored due to lack of coordinated synthesis of both Asian paleoanthropological and paleoclimatic data. Here, we investigate orbital-scale ASM dynamics during the last 280 thousand years (kyr) and their likely influences on early H. sapiens dispersal to East Asia, through a unique integration of i) new centennial-resolution ASM records from the Chinese Loess Plateau, ii) model-based East Asian hydroclimatic reconstructions, iii) paleoanthropological data compilations, and iv) global H. sapiens habitat suitability simulations. Our combined proxy- and model-based reconstructions suggest that ASM precipitation responded to a combination of Northern Hemisphere ice volume, greenhouse gas, and regional summer insolation forcing, with cooccurring primary orbital cycles of ~100-kyr, 41-kyr, and ~20-kyr. Between ~125 and 70 kyr ago, summer monsoon rains and temperatures increased in vast areas across Asia. This episode coincides with the earliest H. sapiens fossil occurrence at multiple localities in East Asia. Following the transcontinental increase in simulated habitat suitability, we suggest that ASM strengthening together with Southeast African climate deterioration may have promoted the initial H. sapiens dispersal from their African homeland to remote East Asia during the last interglacial.
(Proceedings of the National Academy of Sciences of the United States of America. vol. 121, n° 0027-8424, pp. e2308994121, 23/02/2026)
IEE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CUG
Influence of a hydroelectric dam on fish mercury contamination along the Sinnamary River (French Guiana)
The Petit Saut hydroelectric dam and the upstream and downstream areas of the Sinnamary River in French Guiana (Amazon basin) have been studied from 1993 to 2020. The nearly thirty-years-long study of the monitoring of total mercury concentration in fish and the physicochemical survey of the environment made it possible to demonstrate the impact of the flooding of the forest and the role of the hydroelectric dam on the methylation of mercury. Results show that the physicochemical modifications generated by the construction of the dam led to a significant production of methylmercury (MeHg) in the anoxic part of the reservoir and downstream of the river leading to a strong spatio-temporal impact of the dam. Seven species of fishes are studied and their mercury concentrations vary according to many parameters: fish diet, position in the water column, site, lake oxycline level and time.
(Ecotoxicology and Environmental Safety. vol. 269, n° 0147-6513, pp. 115771, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Cardiac and neurobehavioral impairments in three phylogenetically distant aquatic model organisms exposed to environmentally relevant concentrations of boscalid.
Boscalid (2-Chloro-N-(4′-chlorobiphenyl-2-yl) nicotinamide), a pyridine carboxamide fungicide, is an inhibitor of the complex II of the respiration chain in fungal mitochondria. As boscalid is only moderately toxic for aquatic organisms (LC$_{50}$ > 1–10 mg/L), current environmental levels of this compound in aquatic ecosystems, in the range of ng/L-μg/L, are considered safe for aquatic organisms. In this study, we have exposed zebrafish (Danio rerio), Japanese medaka (Oryzias latipes) and Daphnia magna to a range of concentrations of boscalid (1–1000 μg/L) for 24 h, and the effects on heart rate (HR), basal locomotor activity (BLA), visual motor response (VMR), startle response (SR), and habituation (HB) to a series of vibrational or light stimuli have been evaluated. Moreover, changes in the profile of the main neurotransmitters have been determined. Boscalid altered HR in a concentration-dependent manner, leading to a positive or negative chronotropic effect in fish and D. magna, respectively. While boscalid decreased BLA and increased VMR in Daphnia, these behaviors were not altered in fish. For SR and HB, the response was more species- and concentration-specific, with Daphnia exhibiting the highest sensitivity. At the neurotransmission level, boscalid exposure decreased the levels of L-aspartic acid in fish larvae and increased the levels of dopaminergic metabolites in D. magna. Our study demonstrates that exposure to environmental levels of boscalid alters cardiac activity, impairs ecologically relevant behaviors, and leads to changes in different neurotransmitter systems in phylogenetically distinct vertebrate and invertebrate models. Thus, the results presented emphasize the need to review the current regulation of this fungicide.
(Environmental Pollution. vol. 347, n° 0269-7491, pp. 123685, 23/02/2026)
IDAEA, CSIC, URL, CID-CSIC, CSIC, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Temporal distribution of microplastics and other anthropogenic particles in four marine species from the Atlantic coast (France).
The characterization of microplastic (MP) contamination in marine species is increasing as concerns about environmental and food safety are more and more discussed. Here, we reported a quantitative and qualitative assessment of the contamination by anthropogenic particles (from visual sorting; AP) and MP (plastic-made) in the whole soft body or digestive tract of marine species. Four commercial species were studied, namely the Pacific oyster (Magallana gigas), the spiny spider crab (Maja sp.), the common sole (Solea solea) and seabass (Dicentrarchus labrax or punctatus). AP and MP uptake were studied over three to four seasons depending on the species. After tissues digestion, particles were extracted under a stereomicroscope and morphometric characteristics were reported. Then, polymers were identified by ATR-FTIR spectroscopy. Seasonal variations were mainly described in the Pacific oyster as AP uptake was lower in autumn and MP uptake was higher in spring. These variations may be linked to the reproduction and growth cycles of this species. Moreover, seabass ingestion was lower in autumn compared to winter. Contamination in spider crabs and soles showed either weak or no seasonal trends, both quantitatively and qualitatively. Overall, AP contamination in all studied species ranged from 1.17 ± 1.89 AP.ind (in sole) to 4.07 ± 6.69 AP.ind (in seabass) while MP contamination ranged from 0.10 ± 0.37 MP.ind (in sole) to 1.09 ± 3.06 MP.ind (in spider crab). Fibers were mostly reported in all species (at least 77.7%), along with cellulosic polymers (at least 43.7%). AP and MP uptake were detected in all species and at almost all seasons, with the only exception of the common sole during autumn. Therefore, this study emphasizes the ubiquity of AP and MP contamination in marine species and provides new knowledges about seasonal uptake by commercial species.
(Environmental Pollution. vol. 357, n° 0269-7491, pp. 124440, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CBMN, UB, ENITAB, INC-CNRS, CNRS
Pseudopolydora kempi japonica Imajima & Hartman, 1964 (Polychaeta: Spionidae): a controversial subspecies long overlooked in European waters
Recently, using morphological and molecular analyses, several Pseudopolydora specimens (Polychaeta: Spionidae) from French coastal waters were identified as Pseudopolydora kempi ssp. japonica Imajima and Hartman, 1964. According to the samples examined, P. kempi ssp. japonica has been present in European waters since 2004. Previous misidentifications in France are likely due to its resemblance to the indigenous species Pseudopolydora pulchra (Carazzi, 1893), and to the status of P. kempi ssp. japonica which is still controversial. Material was collected from Arcachon Bay, Morbihan Bay, Aiguillon Bay, and in the Gironde estuary (Bay of Biscay, France). All these areas have extensive shellfish industries, especially the farming of the Japanese oyster Magallana gigas (Thunberg, 1793). The importation of these live oysters from Japan has often included other species including polychaete worms, indicating a major vector of exotic species.
(BioInvasions Records. vol. 32, n° 2242-1300, pp. 403-418, 23/02/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UMS POREA, INSU - CNRS, CNRS, INRAE, LIENSs, INSU - CNRS, ULR, CNRS