Spatial variability and sources of platinum in a contaminated harbor – tracing coastal urban inputs
Biogeochemical cycles that include processes to control platinum (Pt) distribution remain widely unknown in aquatic environments, especially in coastal systems. Dissolved Pt concentrations in coastal seawater (PtD) and in suspended particulate matter (SPM, PtP) were measured, together with master variables comprising dissolved oxygen, dissolved and particulate organic carbon, chlorophyll-a, turbidity, and ammonium levels, along two longitudinal profiles in the industrial Genoa Harbor (north-west Italy). Concentrations and spatial distribution of PtD and PtP levels reflect distinct concentration gradients that were attributed to different Pt sources such as hospital, domestic and industrial wastewater, atmospheric deposition, and/or road runoff. Concentrations reaching up to 0.18 ng L−1 PtD and 14 ng g−1 PtP reflect the impact of Pt urban inputs to coastal sites. These first data highlight considerable anthropogenic contamination in a confined harbor compared with the proposed reference value for the western Mediterranean surface seawater measured at external sites. Identified correlations between Pt levels and human pollution signals suggest the potential use of Pt as a new tracer of anthropogenic inputs that can be applied to other urbanised coastal systems. Biogeochemical processes that induce changes in the partitioning and fate of Pt in coastal seawater reflect a spatial variability and highlight the need for comprehensive environmental monitoring at an appropriate spatial scale.
(Environmental Chemistry. vol. 17, n° 1448-2517, pp. 105-117, 01/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UNIGE, UniGe
Introduction to the Special Issue on Breaking Waves
(European Journal of Mechanics - B/Fluids. vol. 73, n° 0997-7546, pp. 1-5, 01/09/2026)
UiB, CARDAMOM, IMB, UB, Bordeaux INP, CNRS, Inria, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, I2M-BX, UB, CNRS, INRAE
Monsoon-driven Saharan dust variability over the past 240,000 years
Reconstructions of past Saharan dust deposition in marine sediments provide foundational records of North African climate over time scales of 10(3) to 10(6) years. Previous dust records show primarily glacial-interglacial variability in the Pleistocene, in contrast to other monsoon records showing strong precessional variability. Here, we present the first Saharan dust record spanning multiple glacial cycles obtained using Th-230 normalization, an improved method of calculating fluxes. Contrary to previous data, our record from the West African margin demonstrates high correlation with summer insolation and limited glacial-interglacial changes, indicating coherent variability in the African monsoon belt throughout the late Pleistocene. Our results demonstrate that low-latitude Saharan dust emissions do not vary synchronously with high-and mid-latitude dust emissions, and they call into question the use of existing Plio-Pleistocene dust records to investigate links between climate and hominid evolution.
(Science Advances. vol. 5, n° 2375-2548, pp. eaav1887, 01/09/2026)
GEOPS, UP11, CNRS, EAPS, MIT, MIT, LDEO, UdeC, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Intratidal and Subtidal Circulation in a Tropical Estuary during Wet Season: The Maroni, French Guiana
Observations of water level, current velocity, river discharge, wind and salinity were collected in the Maroni estuary, on the border of French Guiana and Suriname during the wet season of 2018 to explore subtidal circulation patterns. Measurements are complimented by the application of analytical models with an aim to diagnose forcing mechanisms responsible for producing subtidal flows during the day of data collection and to extrapolate these findings to other time periods with variable wind and river forcing. Subtidal along-channel flows were found to be dominated by river discharge, with seaward directed velocities found throughout the channel section reaching 40 cm s −1. This pattern was altered with strong southwesterly winds, which produced and inverse gravitational circulation pattern despite the elevated river discharge. Secondary, or cross-channel flows, displayed a three-layer vertical structure in the main channel due to a combination of channel curvature and tidal asymmetry in the lateral baroclinic pressure gradient. The pressure gradient was produced by a salinity intrusion front that only manifested in the channel during flood tide. This is the first comprehensive study of tidal and subtidal flow dynamics in the Maroni estuary.
(Journal of Marine Science and Engineering. vol. 7, n° 2077-1312, pp. 433, 01/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LEEISA, IFREMER, UG, CNRS, M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS
Impact of diuron and S-metolachlor on the freshwater diatom Gomphonema gracile: Complementarity between fatty acid profiles and different kinds of ecotoxicological impact-endpoints
Fatty acids (FA) are crucial for the maintenance of membrane fluidity and play a central role in metabolic energy storage. Polyunsaturated fatty acids play an essential ecological role since they are key parameters in the nutritional value of algae. Pesticide impacts on fatty acid profiles have been documented in marine microalgae, but remain understudied in freshwater diatoms. The aims of this study were to: 1) investigate the impact of diuron and S-metolachlor on "classical descriptors" (photosynthesis, growth rate, pigment contents, and on the expression levels of target genes in freshwater diatoms), 2) examine the impact of these pesticides on diatom fatty acid profiles and finally, 3) compare fatty acid profiles and "classical descriptor" responses in order to evaluate their complementarity and ecological role. To address this issue, the model freshwater diatom Gomphonema gracile was exposed during seven days to diuron and S-metolachlor at 10 µg.L.
(Science of the Total Environment. vol. 688, n° 0048-9697, pp. 960-969, 01/09/2026)
UR EABX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LBM, UB, CNRS
Mécanismes : échanges de polluants aux interfaces sol-végétation-atmosphère et devenir dans l’atmosphère
(pp. 73-106, 01/09/2026)
ECOSYS, INRA, LSCE, UVSQ, INSU - CNRS, CNRS, DRF (CEA), CEA, SADAPT, INRAE, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Dispersion des métaux de la mine au lagon : rôle du compartiment atmosphérique et dispersion au sein du compartiment biotique dulçaquicole et estuarien. Rapport scientifique final
Ce rapport du programme DMML « Dispersion des métaux de la mine au lagon » constitue le volume 1 (sur 4) du programme intégré « Dispersion et exposition humaine aux métaux en Nouvelle-Calédonie » composé de 3 projets (DMML, Dynamine, Métexpo) étudiant les métaux et leur toxicité sur des sites pilotes similaires.- Le programme DMML a proposé de caractériser le potentiel de dispersion des éléments métalliques traces (ETM) Ni, Cr, Co et Mn au sein des compartiments abiotiques (atmosphère et pédosphère) et d’évaluer la contamination métallique dans le compartiment biotique de l’hydrosphère ainsi que de déterminer les mécanismes de transferts trophiques. - La caractérisation des flux d’ETM au sein de l’hydrosphère est réalisée dans le programme « Dynamine ».
(pp. 192 p., 01/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ISEA, UNC, ARTeHiS, MCC, UB, CNRS, GSMA, URCA, CNRS
Protective Effects of and Aqueous Extracts against Cadmium- and Mercury-Induced Toxicities
The extracts of and are widely used in the folk medicine. The potential protective effects of these extracts have been evaluated against cadmium in the yeast , and against mercurial contamination in zebrafish . In yeast, both extracts efficiently protected the Δ mutant strain exposed to cadmium chloride restoring the growth, the expression of stress-response genes and decreasing the level of oxidative stress. In zebrafish, the supplementation of methylmercury-contaminated diet with both plant extracts similarly protected fish through the suppression of the methylmercury-induced lipid peroxidation, decrease of acetylcholinesterase activity, and restoring the expression levels of stress-response genes. This study particularly demonstrates the protective potential of both aqueous extracts against methylmercury, and could represent an interesting alternative for the Amazonian fish-eating communities to cope with the impact of chronic exposure to contaminated diets.
(Toxicological Research. vol. 35, n° 1976-8257, pp. 25-35, 01/09/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, UFOPA
Transcriptomic response of the benthic freshwater diatom Nitzschia palea exposed to Few Layer Graphene
Nanotechnology currently undergoes a rising development partly due to the increasing use of carbon-based nanoparticles, such as Few Layer Graphene (FLG). Owing to their numerous applications, their industrial production is likely to lead to environmental release, including into aquatic ecosystems. In this study, a transcriptomic approach was used to assess the effect of FLG at low (0.1 mg.L-1) and high (50 mg.L-1) concentration on the benthic freshwater diatom Nitzschia palea after 48h of exposure. Direct contact with FLG and induced shading were distinguished to compare the transcriptomic responses. Differentially expressed genes between each exposure and control conditions were identified and their functional description was discussed. Slight transcriptomic response related to cell wall repair was observed in diatoms exposed to low FLG concentration. Exposure to high FLG concentration induced a strong response involving 1907 transcripts. Notably, 16 transcripts involved in chlorophyll biosynthesis process were under-expressed (Log2FoldChange between -3 and -1.2),suggesting a down-regulation of photosynthetic metabolism. Diatoms exposed to high FLG concentration over-expressed about 13 transcripts encoding for extracellular proteins playing a role in cellular adhesion, and two highly up-regulated transcripts involved in cell wall repair. Light deprivation caused by shading induced a down-regulation of genes involved in the energetic metabolism of N. palea. Overall, these results revealed that metabolic pathways impacted by FLG exposure were concentration contact-dependent. Moreover, this study suggests that low FLG concentration, close to environmental conditions, will have minor impact on diatom biofilms whereas high FLG concentration, mimicking accidental release, might be critical for ecosystems.
(Environmental science.Nano. vol. 6, n° 2051-8153, pp. 1363-1381, 01/09/2026)
LEFE, INEE-CNRS, CNRS, UT3, Comue de Toulouse, CNRS, Toulouse INP, Comue de Toulouse, GBF, INRA, ENSAT, INP-ENSAT, AgroToulouse, INP-AgroToulouse, Toulouse INP, Comue de Toulouse, Toulouse INP, Comue de Toulouse, CIRIMAT, UT3, Comue de Toulouse, IUT Toulouse Auch Castres, UT3, Comue de Toulouse, INC-CNRS, CNRS, Toulouse INP, Comue de Toulouse, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Devenir des micropolluants et bioindicateur lipidique en Zone de rejet végétalisée
(pp. 18, 01/09/2026)
UR REVERSAAL, IRSTEA, UB, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, IRSTEA