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Legacy and emerging halogenated flame retardants in Lake Geneva fish Texte intégral
2021
Babut, Marc | Marchand, Philippe | Vénisseau, Anaïs | Veyrand, Bruno | Ferrari, Benoit J D | RiverLy - Fonctionnement des hydrosystèmes (RiverLy) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire d'étude des Résidus et Contaminants dans les Aliments (LABERCA) ; École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecole Polytechnique Fédérale de Lausanne (EPFL)
Legacy and emerging halogenated flame retardants in Lake Geneva fish Texte intégral
2021
Babut, Marc | Marchand, Philippe | Vénisseau, Anaïs | Veyrand, Bruno | Ferrari, Benoit J D | RiverLy - Fonctionnement des hydrosystèmes (RiverLy) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire d'étude des Résidus et Contaminants dans les Aliments (LABERCA) ; École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Ecole Polytechnique Fédérale de Lausanne (EPFL)
International audience | Legacy (i.e., polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD)) and alternative halogenated flame retardants (HFRs) were analyzed in 31 whole fish samples from Lake Geneva in 2018. Two fish species, namely, the burbot (Lota lota) and the roach (Rutilus rutilus), were selected, hypothetically representing different habitats, feeding behaviors, and different metabolic capacities. Roach (N = 20) and burbot (N = 11) displayed similar size and mass, but the latter species was overall leaner than the former. The sum of individual PBDE concentrations (0.54–9.86 ng g−1 wet weight (ww)) was similar in both species, but the respective molecular profiles suggested contrasted metabolic capacities. HBCDD sum of isomer concentrations ranged from non-detected to 3.477 ng g−1 (ww), also similar in both species. Both PBDEs and HBCDD levels were far below the threshold that indicates a risk to fish predators. Referring to previous surveys, which involved a wider range of species, PBDE concentrations have declined or are stable. HBCDD concentrations remained low, despite the PBDE ban, which could have fostered the consumption of other HFRs. The occurrence of alternative HFRs was also low for most compounds analyzed. Only dechloranes and decabromodiphenyl ethane (DBDPE) had detection rates above 50%. Dechloranes spanned a concentration range between 5 and 10 times the quantification limits (0.002 to 0.005 ng g−1 wet weight), lower than DBDPE (< 0.005 to 2.89 ng g−1 wet weight). Quality standards targeting biota are currently missing for these emerging chemicals.
Afficher plus [+] Moins [-]Legacy and alternative halogenated flame retardants in Lake Geneva fish Texte intégral
2021
Babut, Marc | Marchand, Philippe | Venisseau, Anaïs | Veyrand, Bruno | Ferrari, Benoit J. D.
Legacy (i.e., polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDD)) and alternative halogenated flame retardants (HFRs) were analyzed in 31 whole fish samples from Lake Geneva in 2018. Two fish species, namely, the burbot (Lota lota) and the roach (Rutilus rutilus), were selected, hypothetically representing different habitats, feeding behaviors, and different metabolic capacities. Roach (N = 20) and burbot (N = 11) displayed similar size and mass, but the latter species was overall leaner than the former. The sum of individual PBDE concentrations (0.54–9.86 ng g⁻¹ wet weight (ww)) was similar in both species, but the respective molecular profiles suggested contrasted metabolic capacities. HBCDD sum of isomer concentrations ranged from non-detected to 3.477 ng g⁻¹ (ww), also similar in both species. Both PBDEs and HBCDD levels were far below the threshold that indicates a risk to fish predators. Referring to previous surveys, which involved a wider range of species, PBDE concentrations have declined or are stable. HBCDD concentrations remained low, despite the PBDE ban, which could have fostered the consumption of other HFRs. The occurrence of alternative HFRs was also low for most compounds analyzed. Only dechloranes and decabromodiphenyl ethane (DBDPE) had detection rates above 50%. Dechloranes spanned a concentration range between 5 and 10 times the quantification limits (0.002 to 0.005 ng g⁻¹ wet weight), lower than DBDPE (< 0.005 to 2.89 ng g⁻¹ wet weight). Quality standards targeting biota are currently missing for these emerging chemicals.
Afficher plus [+] Moins [-]Fate of floating plastic debris released along the coasts in a global ocean model Texte intégral
2021
Chenillat, Fanny | Huck, Thierry | Maes, Christophe | Grima, Nicolas | Blanke, Bruno
Marine plastic pollution is a global issue, from the shores to the open ocean. Understanding the pathway and fate of plastic debris is fundamental to manage and reduce plastic pollution. Here, the fate of floating plastic pollution discharged along the coasts is studied by comparing two sources, one based on river discharges and the other on mismanaged waste from coastal populations, using a Lagrangian numerical analysis in a global ocean circulation model. About 1/3 of the particles end up in the open ocean and 2/3 on beaches. The input scenario largely influences the accumulation of particles toward the main subtropical convergence zones, with the South Pacific and North Atlantic being mostly fed by the coastal population inputs. The input scenario influences the number of beached particles that end up in several coastal areas. Beaching occurs mainly locally, although a significant number of particles travel long distances, allowing for global connectivity.
Afficher plus [+] Moins [-]An appraisal of systematic conservation planning for Pacific Ocean Tropical Islands coastal environments Texte intégral
2021
André, Laure | Van Wynsberge, Simon | Chinain, Mireille | Andrefouet, Serge
Systematic Conservation Planning (SCP) offers concepts and toolboxes to make spatial decisions on where to focus conservation actions while minimizing a variety of costs to stakeholders. Thirty-four studies of Pacific Ocean Tropical Islands were scrutinized to categorize past and current types of applications. It appeared that scenarios were often built on a biodiversity representation objective, opportunity costs for fishers was the most frequent cost factor, and an evolution from simple to sophisticated scenarios followed the need to maximize resilience and connectivity while mitigating climate change impacts. However, proxies and models were often not validated, pointing to data quality issues. Customary management by local communities motivated applications specific to the Pacific region, but several island features remained ignored, including invertebrate fishing, ciguatera poisoning and mariculture. Fourteen recommendations are provided to enhance scenarios' robustness, island specificities integration, complex modelling accuracy, and better use of SCP for island management. Previous article
Afficher plus [+] Moins [-]Distribution of mercury species in different tissues and trophic levels of commonly consumed fish species from the south Bay of Biscay (France) Texte intégral
2021
Mille, Tiphaine | Bisch, Amaëlle | Caill-milly, Nathalie | Cresson, Pierre | Deborde, Jonathan | Gueux, Aurore | Morandeau, Gilles | Monperrus, Mathilde
Mercury (Hg) is a contaminant of global concern in marine ecosystems, notably due to its ability to accumulate and concentrate in food webs. Concentrations of total mercury (THg), methylmercury (MeHg) and inorganic mercury (IHg) were assessed and compared in different tissues (liver, muscle, and gonads) of three common fish species (hake Merluccius merluccius, red mullet Mullus surmuletus, and sole Solea solea) from the continental shelf from the southern part of the Bay of Biscay. Several studies investigated Hg concentration in fish muscle, but few assessed concentrations in other organs, despite the importance of such data to understand contaminant organotropism and metabolization. Results showed that trophic position and feeding habitat are required to understand the variability of Hg concentration in muscle between fish species. In addition, high MeHg/THg ratio in muscle could be explained by the predatory behavior of the studied fish species and the biomagnification of this Hg species within the food web, MeHg. Despite differences between species, Hg concentration was always higher in muscle (from 118 ± 64 to 338 ± 101 ng g−1 w.w.) and liver (from 122 ± 108 to 271 ± 95 ng g−1 w.w.). These results can be related to physiological processes especially the MeHg detoxification strategies.
Afficher plus [+] Moins [-]Changes in benthic macrofauna in oyster parks during an OsHV-1 μVar oyster spat mortality outbreak Texte intégral
2021
Vanhuysse, Charles | Normand, Julien | Lepoittevin, Mélanie | Orvain, Francis
In intertidal areas, oyster farming creates a crosshatching pattern between oyster tables and aisles. Tables provide a refuge from the current and solar irradiance and the oysters facilitate the accumulation of OM, thereby structuring the spatial organization of the associated macrozoobenthic community at mesoscale. The aim of this study was to describe the quality of the oyster table environment at small scale and the response of the macrozoobenthic community to OsHV-1 μvar oyster mortality. The species assemblage was dominated by Golfingia vulgaris, Tubificoides benedii, Capitella capitata and Scoloplos armiger. The table habitat appeared to be in a bad ecological state throughout the 2-month survey (May and June 2017), whereas in the aisle, eutrophication occurred lately and was clearly related to be due to the massive stranding of dead seaweed at the end of the survey (in early July). So, this disturbance of the species assemblage seemed to occur in two phases: 1) after oyster spat mortality and 2) after seaweed stranding resulted in a bad ecological status, as revealed by macrofaunal indicators. Large quantities of OsHV-1 DNA were also found in some species, including small crabs and amphipods, one week after the mortality crisis, but there is no apparent virus reservoir found in the benthic species.
Afficher plus [+] Moins [-]Biogeochemical model of nitrogen cycling in Ahe (French Polynesia), a South Pacific coral atoll with pearl farming Texte intégral
2021
Seceh, C. | Pinazo, C. | Rodier, Martine | Lajaunie-salla, K. | Mazoyer, C. | Grenz, C. | Le Gendre, Romain
A biogeochemical model (ECO3M-Atoll) was configured to simulate the lower food web in Ahe Atoll lagoon where phytoplankton is mostly nitrogen limited. Understanding the dynamics of phytoplankton – the main food source for oysters – is crucial for the management and the allocation of new pearl farming sites. After parametrizing the model with in situ observations, we tested different hypotheses about nitrogen cycling (benthic remineralization, atmospheric N fixation, etc.) and compared the results to a large observational dataset. Model results show that simulated (pico- and nano-) phytoplankton biomass and nitrogen concentrations are close to in situ data. The simulated biogeochemical processes (uptake and primary production) are also very similar to the observed values. In the model, primary production ranged from 1.00 to 2.00 mg C m−3 h−1 for pico- and 0.40 to 1.00 mg C m−3 h−1 for nanophytoplankton; mean N uptake was 2.02 μmol N m−3 h−1 for pico- and 1.25 μmol N m−3 h−1 for nanophytoplankton.
Afficher plus [+] Moins [-]Development in the European flounder (Platichthys flesus) of a q-PCR assay for the measurement of telomere length, a potential biomarker of pollutant effects for biomonitoring studies Texte intégral
2021
Akcha, Farida | Cahuc, C. | Rouxel, Julien | Munschy, Catherine | Aminot, Yann | Chouvelon, Tiphaine | Mahe, Kelig | Budzinski, H. | Mauffret, Aourell
Telomeres protect the coding sequence of chromosome ends and Telomere Length (TL) has been proposed as a biomarker of cellular aging, cumulative stress exposure and life-span in humans. With the aim to propose new biomarkers, a q-PCR protocol was adapted for the measurement of TL in the European flounder Platichthys flesus. The protocol was then applied in 2-year-old flounders from the Seine Estuary. The absolute TL in the flounder is 54 ± 13 kbp per genome (mean ± standard error). Considering relative or absolute TL, no correlation was observed with DNA damage and any of the measured contaminant concentrations (trace elements, metabolites of polycyclic aromatic hydrocarbons, polychlorobiphenyls, organochlorinated pesticides, polybrominated diphenyl ethers, perfluoroalkyl substances). Because sampling was limited, further investigations are required to state a possible impact of chemical pollution on flatfish telomeres. This is motivated by correlations observed with organochlorinated compounds when decreasing statistical significance (p ≤ 0.10).
Afficher plus [+] Moins [-]Documenting decadal disturbance dynamics reveals archipelago-specific recovery and compositional change on Polynesian reefs Texte intégral
2021
Pérez-rosales, Gonzalo | Brandl, Simon J. | Chancerelle, Yannick | Siu, Gilles | Martinez, Elodie | Parravicini, Valeriano | Hédouin, Laetitia
Coral reefs are declining at an unprecedented rate as a consequence of local and global stressors. Using a 26-year monitoring database, we analyzed the loss and recovery dynamics of coral communities across seven islands and three archipelagos in French Polynesia. Reefs in the Society Islands recovered relatively quickly after disturbances, which was driven by the recovery of corals in the genus Pocillopora (84% of the total recovery). In contrast, reefs in the Tuamotu and Austral archipelagos recovered poorly or not at all. Across archipelagos, predation by crown-of-thorns starfish and destruction by cyclones outweighed the effects of heat stress events on coral mortality. Despite the apparently limited effect of temperature-mediated stressors, the homogenization of coral communities towards dominance of Pocillopora in the Society Archipelago and the failure to fully recover from disturbances in the other two archipelagos concern the resilience of Polynesian coral communities in the face of intensifying climate-driven stressors.
Afficher plus [+] Moins [-]The wave regimes of the Central Pacific Ocean with a focus on pearl farming atolls Texte intégral
2021
Dutheil, Cyril | Jullien, Swen | Aucan, J. | Menkes, C. | Le Gendre, Romain | Andréfouët, S.
Pearl farming sustainability in South Central Pacific (SCP) atolls strongly depends on water quality and renewal. These factors are partly controlled by the wave conditions that impact the lagoon circulation. To characterize the wave conditions around 83 SCP atolls including those hosting pearl farming activities, we used 18 years of WaveWatchIII simulation with a grid refined from 50 to 5 km resolution. Three regional wave regimes are statistically identified: two associated with long distant swells originating from mid-latitude storms, and one with local trade winds. All regimes occur with a relatively high frequency (22–44%), but with a marked seasonality. Wave conditions are also strongly modified locally during their propagation between the archipelagoes. Western and southern isolated atolls generally have a single regime all around their rims. In contrast, central Tuamotu atolls experience different regimes depending on their levels of protection. These results help understanding atoll hydrodynamics, which has implications for their management.
Afficher plus [+] Moins [-]Understanding connectivity of pearl oyster populations within Tuamotu atoll semi-closed lagoons: Cumulative insight from genetics and biophysical modelling approaches Texte intégral
2021
Andréfouët, Serge | Le Gendre, Romain | Thomas, Yoann | Lo-yat, Alain | Reisser, Celine
Connectivity affects species demography, (meta)population dynamics, evolution, phylogeny and biogeography. Various methodological approaches are applied to measure connectivity. Biophysical modelling can explore systematically the influence of atmospheric, oceanic and ecological forcing, while genetics measures connectivity patterns within the sampling strategy limit. In the Pacific Ocean pearl farming lagoons, the activity relies on spat collecting of the black lipped pearl oyster Pinctada margaritifera occurring after the larval dispersal phase, which follows spawning from wild or farmed populations. Biophysical 3D modelling and genomic studies have both separately brought insights on within-lagoon connectivity and on the origin of spats. Here, we combined previous genetics results with new realistic biophysical modelling scenarios to elucidate connectivity in Ahe Atoll lagoon. When combined, we identified the weather sequence likely explaining the realized connectivity observations. We discuss the strengths, weaknesses, opportunities and threats of combining these two approaches considering specific pearl farming demographic connectivity questions.
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