PAHs and fish-exposure monitoring and adverse effects-from molecular to individual level
Polycyclic aromatic hydrocarbons (PAHs) are a diverse family of more than one hundred compounds, containing at least two aromatic rings. In addition to parent compounds, the PAH family also includes substituted derivatives, bearing one or several alkyl groups, sulfur, or oxygen. In the environment, PAHs are ubiquitous and present as very complex mixtures. They can also be associated with metallic and/or other organic compounds. The composition of PAH mixtures depends on their origin. There are two major types of such PAH mixtures, petrogenic and pyrogenic, which enter the environment through different routes. Petrogenic mixtures originate from oils, including natural oil seeps. They enter the aquatic environment due to harbor activity or soil runoff or as a consequence of oil spills. Pyrolytic mixtures result from the incomplete combustion of organic matter, including fossil fuel, entering aquatic environments through deposits of atmospheric emissions directly into water or soil, followed by soil erosion and runoff. Directly linked to human activity, the release of PAHs into the environment has increased over the last few decades. As an example, the amount of PAHs released into the atmosphere has dramatically increased from under 50,000 tons in 1987 (Eisler 1987) to over 500,000 tons in 2004 (Zhang and Tao 2009)
(Environmental Science and Pollution Research. vol. 21, n° 0944-1344, pp. 13685-13688, 26/06/2026)
LPGP, INRA, Biosit : Biologie - Santé - Innovation Technologique, BE, IFREMER, UB, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Removal of Micropollutants from Secondary Effluents and Sludge by Various Processes in Rural and Peri-urban Areas
The present work details the results of a comprehensive study dealing with the fate of several families of micropollutants (with various physicochemical properties) through tertiary treatment processes of water and through sludge treatments. Powerful and sensitive analytical techniques were used: 16 metals and 39 organics (pharmaceuticals, polycyclic aromatic hydrocarbons, alkylphenols, pesticides) were analysed in wastewaters; 14 metals and 62 organic hydrophobic micropollutants were measured in sludge (estrogenic hormones, polychlorinated byphenyl, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, alkylphenols and other organics). We studied treatment processes adapted for rural areas involving low energy-consumption: trench system, polishing pond, horizontal subsurface flow constructed wetlands with various adsorbing materials (i.e. expanded clay, zeolite, activated carbon, apatite, gravels) running at tertiary stage of water treatment; and sludge drying reed-bed operated at two different resting periods. Our results show that the trench system was not efficient for additional removal of refractory micropollutants. The polishing pond had higher removal efficiencies (between 30 and 70%) for some pharmaceuticals due to indirect photodegradation. The horizontal subsurface flow constructed wetland (HSSF-CW) built with activated carbon showed almost full-removal during more than 330 days for pharmaceuticals, pesticides, several metals and nonylphenoxyacetic acid. For the HSSF-CWs built with expanded clay or zeolite, we obtained removal efficiencies of 70% for half of studied pharmaceuticals and alkylphenols mono- and di-ethoxylates. The removal efficiencies of other substances were much lower than the ones measured with activated carbon, but they were still higher than the ones measured with gravel (filter designed for denitrification) or apatite (designed for phosphorus removal). Due to better oxygen conditions, the sludge drying reed-bed with low frequency of sludge input resulted in better removal for organic micropollutants than the sludge drying reed-bed with high frequency of sludge input.
(pp. 5 p., 26/06/2026)
UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, CIRSEE
Living (stained) deep-sea Foraminifera off Hachinohe (NE Japan, Western Pacific): environmental interplay in oxygen-depleted ecosystems
Live (Rose-Bengal stained) deep-sea foraminiferal faunas have been studied at five stations between 500–2000-m depth along the NE Japanese margin (western Pacific) to understand how complex environmental conditions (e.g., oxygen depletion, organic matter) control their structure (i.e., diversity, standing stocks, and microhabitats). All stations are characterized by silty sediments with no evidence of recent physical disturbances. The three stations located between 760–1250 m are bathed by dysoxic bottom waters (<45 μmol/L). Although high organic-carbon contents are recorded at all stations (>2.2% DW), only the oxygen-depleted sites are characterized by higher concentrations of sugars, lipids, and enzymatically hydrolysable amino acids (EHAA). Sedimentary contents in chlorophyllic pigments decrease with water depth without any major change in their freshness (i.e., [Chl a/(Chl a + Pheo a)] ratios). Both Uvigerina akitaensis and Bolivina spissa are restricted to the stations bathed by dysoxic waters, proving their oxygen-depletion tolerance. In such conditions, both phytophagous taxa are obviously able to take advantage of labile organic compounds (e.g., lipids and EHAA) contained in phytodetritus. Nonionella stella and Rutherfordoides cornuta survive in oxygen-depleted environments probably via alternative metabolic pathways (e.g., denitrification ability) and a large flexibility in trophic requirements. At stations where oxygen availability is higher (i.e., >70 μmol/L in bottom water) and where bioavailable organic compounds are slightly less abundant, diversity indices remain low, and more competitive species (e.g., Uvigerina curticosta, U. cf. U. graciliformis, Nonionella globosa, Nonionellina labradorica, and Elphidium batialis) are dominant.
(Journal of Foraminiferal Research. vol. 44, n° 0096-1191, pp. p. 281-299, 26/06/2026)
GM, IFREMER, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, JAMSTEC, CEFREM, UPVD, INSU - CNRS, CNRS, CEREGE, IRD, INRA, AMU, CdF (institution), INSU - CNRS, CNRS, NIOZ
A chacun ses sciences participatives : Les conditions d’un observatoire participatif de la biodiversité sur le Bassin d’Arcachon
Cet article analyse les conditions préalables à la création d’un observatoire de sciences participatives de la biodiversité sur le Bassin d’Arcachon. L’enquête sociologique révèle les tensions entre finalités utilitaristes de recueil de données, nouveau mode collaboratif de construction des savoirs, instrument de communication politique, et démarche de vigilance citoyenne ; entre définition concertée de principes d’organisation des dispositifs et contrôle de positions de pouvoir sur le territoire. Loin du consensus apparent sur la protection de la biodiversité, le positionnement des acteurs du territoire redéfinit les enjeux environnementaux, précise les relations sciences - société et esquisse de nouvelles hiérarchies des priorités de gestion. / This paper considers the social and scientific requirements for a Citizen science monitoring programme on biodiversity in Arcachon Bay (France). The sociological study reveals tensions between different conceptions of what a Citizen science programme should be: a means for storing oriented-data; a new way to cocreate scientific knowledge; a political communication tool; a way to develop Citizen stewardship; or a place for expressing activist environmental demands. Citizen science programmes also tend to reveal tensions between participatory governance and classical management of environmental issues. Despite a seeming consensus amongst actors on biodiversity conservation, in practice contests over different citizen science conceptions have the potential to re-define environmental issues, to re-specify relationships between science and society and outline new management priorities.
(ESSACHESS – Journal for Communication Studies. vol. 7, n° 2066-5083, pp. p. 93 - p. 106, 26/06/2026)
UR ADBX, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Environmental effects of realistic pesticide mixtures on natural biofilm communities with different exposure histories
This study deals with the use of Polar Organic Chemical Integrative Sampler (POCIS) extracts to assess the impact of low-dose pesticide mixtures on natural biofilm communities originating from either a chronically contaminated or a reference field site. To investigate how natural biofilm communities, pre-exposed to pesticides in situ or not might respond to environmentally realistic changes in pesticide pressure, they were exposed to either clean water or to POCIS extracts (PE) in order to represent toxic pressure with a realistic pesticide mixture directly isolated from the field. The impacts of PE were assessed on structure, physiology and growth of biofilms. Initial levels of tolerance of phototrophic communities to PE were also estimated at day 0. PE exposure led to negative effects on diatom growth kinetics independently of in-field biofilm exposure history. In contrast, the impacts observed on dry weight, ash-free dry mass and algal fluorescence-related parameters followed different trends depending on biofilm origin. Exposure to PE induced changes in diatom assemblages for the biofilm originating from the reference field site with higher relative abundance of Eolimna minima and Nitzschia palea with PE exposure. Initial tolerance of phototrophic communities to PE was 8-fold higher for the biofilm originating from the chronically contaminated site compared to the reference field site. The use of POCIS extracts allowed us to highlight both chronic impacts of low doses of a mixture of pesticides on natural communities with regard to biofilm exposure history as well as initial levels of tolerance of phototrophic communities.
(Science of the Total Environment. vol. 473–474, n° 0048-9697, pp. 496-506, 26/06/2026)
UR EABX, IRSTEA, UR MALY, IRSTEA, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Geochemical composition of Trondheimsfjord surface sediments: Sources and spatial variability of marine and terrigenous components
High sedimentation rates in fjords provide excellent possibilities for high resolution sedimentary and geochemical records over the Holocene. As a baseline for an improved interpretation of geochemical data from fjord sediment cores, this study aims to investigate the inorganic/organic geochemistry of surface sediments and to identify geochemical proxies for terrestrial input and river discharge in the Trondheimsfjord, central Norway. Sixty evenly distributed surface sediment samples were analysed for their elemental composition, total organic carbon (C org), nitrogen (N org) and organic carbon stable isotopes (δ 13 C org), bulk mineral composition and grain size distribution. Our results indicate carbonate marine productivity to be the main CaCO 3 source. Also, a strong decreasing gradient of marine-derived organic matter from the entrance towards the fjord inner part is consistent with modern primary production data. We show that the origin of the organic matter as well as the distribution of CaCO 3 in Trondheimsfjord sediments can be used as a proxy for the variable inflow of Atlantic water and changes in river runoff. Furthermore, the comparison of grain size independent Al-based trace element ratios with geochemical analysis from terrigenous sediments and bedrocks provides evidence that the distribution of K/Al, Ni/Al and K/Ni in the fjord sediments reflect regional sources of K and Ni in the northern and southern drainage basin of the Trondheimsfjord. Applying these findings to temporally well-constrained sediment records will provide important insights into both the palaeoenvironmental changes of the hinterland and the palaeoceanographic modifications in the Norwegian Sea as response to rapid climate changes and associated feedback mechanisms.
(Continental Shelf Research. vol. 88, n° 0278-4343, pp. 61-71, 26/06/2026)
UiT, NGU, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Flash rip dynamics on a high-energy low-tide-terraced beach (Grand Popo, Benin, West Africa)
Rip currents are wave-driven intense seaward-flowing jets of water that are important to both beach morphodynamics and the overall ecosystem. Rip currents are also the leading deadly hazard to recreational beach users worldwide. More specifically, the African region is reported to have the highest rates of drowning in the world, yet both the occurrence and the type of rips developing along the African beaches are unknown. In February 2013, a 12-day field experiment was performed at the high-energy low-tide-terraced sandy beach of Grand Popo beach (Benin, West Africa). Human drifter data and video imagery are combined to address wave-driven circulation and rip current activity. Results show two prevailing rip current types. (1) Low-energy (~0.2-0.4 m/s) swash rips, with short life-spans of about 1 minute, extend about 5-10 m offshore and occur preferably at mid to high tide at fixed locations in the center of beach cusps. (2) Higher-energy (0.2 - 0.8 m/s) surfzone flash rips become active with the onset of intense wave breaking across the low-tide terrace. They tend to migrate downdrift with alonger time-span of about 2-5 minutes. The relatively weak longshore current (0.2 - 0.55 m/s) measured during the experiment suggests that flash rips were driven by vorticity generated by wave breaking rather than shear instabilities of the longshore current. Swash rips and flash rips are common at Grand Popo and often co-exist. We propose a conceptual model of both flash and swash rip activity on this stretch of the West African coast.
(Journal of Coastal Research. vol. SI 70, n° 0749-0208, pp. 633-638, 26/06/2026)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, ECOLA, LEGOS, IRD, UT3, Comue de Toulouse, INSU - CNRS, CNES, CNRS, CEREGE, IRD, INRA, AMU, CdF (institution), INSU - CNRS, CNRS, IRD [France-Ouest]
Multi-agent modelling of the trajectory of the LBK Neolithic: a study in progress
(26/06/2026)
EVS, ENS de Lyon, Mines Saint-Étienne MSE, IMT, UL2, UJML, INSA Lyon, INSA, UJM, UJM EPE, ENTPE, ENSAL, CNRS, ALLHiS, UJM, UJM EPE, ArScAn, UP1, UP8, UPN, MCC, CNRS, UMR LISAH, IRD, INRA, Montpellier SupAgro, Montpellier SupAgro, BioArch, MNHN, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, Inrap, CEPAM, UNS, CNRS, REEDS, UVSQ
Late Holocene surface water changes in the eastern Nordic Seas : the message from carbonate and organic-walled phytoplankton microfossils
Five marine sediment cores distributed along the Norwegian, western Barents Sea, and Svalbard continental margins have been investigated in order to reconstruct late Holocene changes in the poleward flow of the Norwegian Atlantic Current (NwAC) and West Spitsbergen Current (WSC) and the nature of the upper surface water masses within the eastern Nordic Seas. This research project is based on the use of dinocyst and coccolith assemblages for qualitative and quantitative reconstructions of surface water conditions from high resolution sediment cores, and involve upstream investigations on proxy reliabilities. The investigated area (66 to 77°N) was affected by an overall increase in the strength of the AW flow from 3000 cal. yrs BP to the Present. The long-term modulation of westerlies strength and location which are essentially driven by the dominant mode of the North Atlantic Oscillation (NAO), is thought to explain the observed dynamics of the AW flow. The same mechanism also reconciles the recorded opposite zonal shifts in the location of the Arctic Front between the area off western Norway and the western Barents Sea-eastern Fram Strait region. Submillenial changes in AW flow are organised according to known pre-Anthropocene warm (RWP, MCA and the Modern period: strong poleward flow) and cold (LIA, DA: weak poleward flow) climatic spells. A sudden short pulse of resumed high WSC flow interrupted the LIA in the eastern Nordic Seas from 330 to 410 cal. yrs BP. Our results are indicative of a major impact of AW flow dynamics on the Arctic sea ice distribution during the last millenium, when changes in reconstructed sea-ice extent are negatively correlated with the strength of the WSC flow off western Barents Sea and western Svalbard. The extensive decrease in sea ice extent during the last century is synchronous with an exceptional increase in AW flow. The previously reconstructed high amplitude warming of surface waters in eastern Fram Strait at the turn of the 19th century was therefore primarily induced by an excess flow of AW which stands as unprecedented over the last 3000 years.
(17/12/2013)
EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS
Turbulence and sediment transport over sand dunes and ripples
(15/12/2013)
M2C, UNICAEN, NU, INSU - CNRS, UNIROUEN, NU, CNRS, EPOC, EPHE, PSL, UB, INSU - CNRS, CNRS, LOS, IFREMER