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Resultados 161-170 de 5,152
Large-scale geographic patterns of mercury contamination in Morocco revealed by freshwater turtles Texto completo
2018
Slimani, Tahar | El Hassani, Mohamed Said | El Mouden, El Hassan | Bonnet, Marine | Bustamante, Paco | Brischoux, Francois | Brault-Favrou, Maud | Bonnet, Xavier | Faculté des Sciences Semlalia [Marrakech] ; Université Cadi Ayyad [Marrakech] (UCA) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS) | LIttoral ENvironnement et Sociétés (LIENSs) ; Institut national des sciences de l'Univers (INSU - CNRS)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)
Large-scale geographic patterns of mercury contamination in Morocco revealed by freshwater turtles Texto completo
2018
Slimani, Tahar | El Hassani, Mohamed Said | El Mouden, El Hassan | Bonnet, Marine | Bustamante, Paco | Brischoux, Francois | Brault-Favrou, Maud | Bonnet, Xavier | Faculté des Sciences Semlalia [Marrakech] ; Université Cadi Ayyad [Marrakech] (UCA) | Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC) ; Institut National de la Recherche Agronomique (INRA)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS) | LIttoral ENvironnement et Sociétés (LIENSs) ; Institut national des sciences de l'Univers (INSU - CNRS)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)
International audience | Mercury (Hg) is a toxic contaminant present in most aquatic ecosystems. High concentrations pose serious threats to organisms and to human health. Because previous studies focused on few countries, environmental hazard due to Hg contamination remains obscure in many geographic areas, and for example limited information is available in North Africa. We examined total Hg contamination in 13 sites in Morocco (12 rivers and one lake) spread over a large area, 400 km north–south and 350 km west–east, that encompasses different biogeographic zones separated by the Atlas Mountains. Due to their longevity and sedentary habits, we used freshwater turtles as biological probes to monitor Hg exposure. Keratinized tissues reflect long-term Hg exposure; thus, we assayed Hg concentration in the claws of > 200 individuals and supplemented these data with blood Hg concentrations of > 60 individuals (a tissue that provides shorter term Hg exposure integration). The results provide the first large-scale picture of Hg contamination in the aquatic freshwater systems of Morocco. Comparisons with previous studies revealed that some of the sites were highly contaminated (e.g. mean Hg concentrations were above 5 μg g⁻¹, a very high level in keratinized tissues) whereas other sites presented moderate or baseline levels. Unexpectedly, all highly contaminated sites were found in less densely populated areas, while more densely urbanized northern sites, even the sewers of large cities, were not highly contaminated. We hypothesize that silver mining activities in the southern High Atlas and in the Anti-Atlas contaminate rivers of the catchment basins over long distances. These findings indicate that fish, water consumption and contamination levels in local people should be further scrutinized.
Mostrar más [+] Menos [-]Large-scale geographic patterns of mercury contamination in Morocco revealed by freshwater turtles Texto completo
2018
Slimani, Tahar | El Hassani, MohamedSaid | El Mouden, ElHassan | Bonnet, Marine | Bustamante, Paco | Brischoux, François | Brault-Favrou, Maud | Bonnet, Xavier
Mercury (Hg) is a toxic contaminant present in most aquatic ecosystems. High concentrations pose serious threats to organisms and to human health. Because previous studies focused on few countries, environmental hazard due to Hg contamination remains obscure in many geographic areas, and for example limited information is available in North Africa. We examined total Hg contamination in 13 sites in Morocco (12 rivers and one lake) spread over a large area, 400 km north–south and 350 km west–east, that encompasses different biogeographic zones separated by the Atlas Mountains. Due to their longevity and sedentary habits, we used freshwater turtles as biological probes to monitor Hg exposure. Keratinized tissues reflect long-term Hg exposure; thus, we assayed Hg concentration in the claws of > 200 individuals and supplemented these data with blood Hg concentrations of > 60 individuals (a tissue that provides shorter term Hg exposure integration). The results provide the first large-scale picture of Hg contamination in the aquatic freshwater systems of Morocco. Comparisons with previous studies revealed that some of the sites were highly contaminated (e.g. mean Hg concentrations were above 5 μg g⁻¹, a very high level in keratinized tissues) whereas other sites presented moderate or baseline levels. Unexpectedly, all highly contaminated sites were found in less densely populated areas, while more densely urbanized northern sites, even the sewers of large cities, were not highly contaminated. We hypothesize that silver mining activities in the southern High Atlas and in the Anti-Atlas contaminate rivers of the catchment basins over long distances. These findings indicate that fish, water consumption and contamination levels in local people should be further scrutinized.
Mostrar más [+] Menos [-]Reconstructing long-term trajectories of fish assemblages using historical data: the Seine River basin (France) during the last two centuries Texto completo
2018
Belliard, Jérôme | Beslagic, S. | Delaigue, Olivier | Tales, Evelyne | Hydrosystèmes continentaux anthropisés : ressources, risques, restauration (UR HYCAR) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Hydrosystèmes et Bioprocédés (UR HBAN) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | POLE D'HISTOIRE ENVIRONNEMENTALE UNIVERSITY OF NAMUR BEL ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]QUASARE [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | We used historical sources from the end of the nineteenth to the mid-twentieth century and current data to retrace fish assemblage trajectories for the past 150 years on 29 river stretches distributed throughout the Seine River basin. We based our analyses on species presence/absence, occurrence of amphidromous and non-native species, and species ecological traits related to habitat preference, oxygen and temperature requirements, and diet. In accordance with general trends observed for Western Europe, we detected a general decline of amphidromous species and an increase in nonnative species, even if, at some sites, several non-native species were extirpated. These changes affecting amphidromous and non-native species led to a weak increase in beta-diversity in fish assemblages. Independently of amphidromous and non-native species, for a reduced set of sites, we noted that changes in the balance of ecological traits over time, trace, in a consistent way, the major steps that affected watercourses like waterway development, increasing pollution, dam construction, or, locally, the recent wastewater treatment improvement. Despite local variations, we found contrasted trends between, on one hand, large rivers and/or catchments which had experienced strong expansion in human population, where fish assemblages had deteriorated, and, on the other hand, upstream catchments, with a declining human population, where fish assemblages showed signs of improvement. Because our results suggested that long-term changes affecting fish assemblages cannot be summarized as an unequivocal gradual degradation, we questioned the use of historical data to define ecological reference conditions for river assessment and management purposes.
Mostrar más [+] Menos [-]Evaluation of psychiatric hospital wastewater toxicity: what is its impact on aquatic organisms? Texto completo
2018
Mazzitelli, Jean-Yves | Budzinski, Hélène | Cachot, Jérôme | Geffard, Olivier | Marty, Pierre | Chiffre, Axelle | François, Adeline | Bonnafé, Elsa | Geret, Florence | Biochimie et Toxicologie des Substances Bioactives (BTSB) ; Institut national universitaire Champollion (INUC) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Laboratoire de Physico et Toxico-Chimie des systèmes naturels (LPTC) ; Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Laboratoire de Parasitologie-Mycologie, Nice ; Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre Hospitalier Universitaire de Nice (CHU Nice)-Université Côte d'Azur (UniCA) | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Géographie de l'environnement (GEODE) ; Université Toulouse - Jean Jaurès (UT2J) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) | This work was supported by ANSES, the Adour-Garonne Water Agency, and the Midi-Pyrénées region.
Evaluation of psychiatric hospital wastewater toxicity: what is its impact on aquatic organisms? Texto completo
2018
Mazzitelli, Jean-Yves | Budzinski, Hélène | Cachot, Jérôme | Geffard, Olivier | Marty, Pierre | Chiffre, Axelle | François, Adeline | Bonnafé, Elsa | Geret, Florence | Biochimie et Toxicologie des Substances Bioactives (BTSB) ; Institut national universitaire Champollion (INUC) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Laboratoire de Physico et Toxico-Chimie des systèmes naturels (LPTC) ; Université Sciences et Technologies - Bordeaux 1 (UB)-Centre National de la Recherche Scientifique (CNRS) | Environnements et Paléoenvironnements OCéaniques (EPOC) ; École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Laboratoire de Parasitologie-Mycologie, Nice ; Université Nice Sophia Antipolis (1965 - 2019) (UNS)-Centre Hospitalier Universitaire de Nice (CHU Nice)-Université Côte d'Azur (UniCA) | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Géographie de l'environnement (GEODE) ; Université Toulouse - Jean Jaurès (UT2J) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS) | This work was supported by ANSES, the Adour-Garonne Water Agency, and the Midi-Pyrénées region.
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples <br/>[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | The primary source of pharmaceuticals to the aquatic environment is the discharge of wastewater effluents. Pharmaceuticals are a large and diverse group of compounds. Among them, psychotropic substances are particularly interesting to study due to their specific known mode of action. The present study was performed to investigate the effects of wastewater effluents from a psychiatric hospital wastewater treatment plant (WWTP) on several aquatic organisms. All the analyzed pharmaceuticals (10 compounds) were detected in WWTP effluents as well as in the receiving river. Although the environmental concentrations were generally at trace levels (ng L-1 to μg L-1), induce toxic effects were observed. This study showed the effects of the WWTP effluents on the oogenesis and/or embryogenesis of amphipod crustacean Gammarus fossarum, Japanese fish medaka Oryzias latipes, mollusk Radix peregra, and planarian Schmidtea polychroa. A decrease of the number of oocytes and produced embryos was observed for G. fossarum and S. polychroa. Similarly, the hatching rate of R. peregra was affected by effluents. In the receiving river, the macroinvertebrate community was affected by the wastewater effluents discharge.
Mostrar más [+] Menos [-]Evaluation of psychiatric hospital wastewater toxicity: what is its impact on aquatic organisms? Texto completo
2018
Mazzitelli, Jean-Yves | Budzinski, Hélène | Cachot, Jérôme | Geffard, Olivier | Marty, Pierre | Chiffre, Axelle | François, Adeline | Bonnafe, Elsa | Geret, Florence
The primary source of pharmaceuticals to the aquatic environment is the discharge of wastewater effluents. Pharmaceuticals are a large and diverse group of compounds. Among them, psychotropic substances are particularly interesting to study due to their specific known mode of action. The present study was performed to investigate the effects of wastewater effluents from a psychiatric hospital wastewater treatment plant (WWTP) on several aquatic organisms. All the analyzed pharmaceuticals (10 compounds) were detected in WWTP effluents as well as in the receiving river. Although the environmental concentrations were generally at trace levels (ng L⁻¹ to μg L⁻¹), induce toxic effects were observed. This study showed the effects of the WWTP effluents on the oogenesis and/or embryogenesis of amphipod crustacean Gammarus fossarum, Japanese fish medaka Oryzias latipes, mollusk Radix peregra, and planarian Schmidtea polychroa. A decrease of the number of oocytes and produced embryos was observed for G. fossarum and S. polychroa. Similarly, the hatching rate of R. peregra was affected by effluents. In the receiving river, the macroinvertebrate community was affected by the wastewater effluents discharge.
Mostrar más [+] Menos [-]Pesticide residue profiles in bee bread and pollen samples and the survival of honeybee colonies: a case study from Luxembourg Texto completo
2018
Beyer, M. | Lenouvel, A. | Guignard, C. | Eickermann, M. | Clermont, Antoine | Kraus, F. | Hoffmann, - | ENVIRONMENTAL RESEARCH AND INNOVATION DEPARTMENT LUX ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Information – Technologies – Analyse Environnementale – Procédés Agricoles (UMR ITAP) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | ADMINISTRATION DES SERVICES TECHNIQUES DE L'AGRICULTURE LUXEMBOURG LUX ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]INSPIRE [ADD1_IRSTEA]Équiper l'agriculture | International audience | Pesticide residues (112 compounds) were quantified by GC-MS/MS or LC-MS/MS in 85 bee bread samples and 154 pollen samples obtained from five apiaries each with three or four colonies (genotype Buckfast) in Luxembourg over the period 2011-2013. Thiacloprid, chlorfenvinphos, tebuconazole, and methiocarb were found most frequently in bee bread while thiacloprid, permethrin-cis, and permethrin-trans were detected most frequently in the pollen samples. Three neonicotinoid insecticides (clothianidin, imidacloprid, and thiamethoxam) that were restricted by an EU regulation in 2013 after our sampling campaign was finished were each found in less than 8% of the pollen or bee bread samples. The maximum concentrations of thiacloprid, metazachlor, and methiocarb measured in the pollen collected by a group of honeybee colonies (n=5) without survivors within the 3-year period of observation were 86.20 +/- 10.74ng/g, 2.80 +/- 1.26ng/g, and below the limit of quantification, respectively. The maximum concentrations of the same compounds measured in the pollen collected by a group of honeybee colonies with significantly (P=0.02) more survivors (7 out of 9) than expected, if the survivors had been distributed randomly among the groups of colonies, were 11.98 +/- 2.28ng/g, 0.44 +/- 0.29ng/g, and 8.49 +/- 4.13ng/g, respectively. No honeybee colony that gathered pollen containing more than 23ng/g thiacloprid survived the 3-year project period. There was no statistically significant association between pesticide residues in the bee bread and the survival of the colonies. Actions already taken or planned and potential further actions to protect bees from exposure to pesticides are discussed.
Mostrar más [+] Menos [-]One more step toward a push-pull strategy combining both a trap crop and plant volatile organic compounds against the cabbage root fly Delia radicum. Texto completo
2018
Lamy, Fabrice | Dugravot, Sébastien | Cortesero, Anne-Marie | Chaminade, Valérie | Faloya, Vincent | Poinsot, Denis | Institut de Génétique, Environnement et Protection des Plantes (IGEPP) ; Institut National de la Recherche Agronomique (INRA)-Université de Rennes (UR)-AGROCAMPUS OUEST | Project "PURE" | French ministry for research
International audience | The "push-pull" strategy aims at manipulating insect pest behavior using a combination of attractive and repulsive stimuli using either plants derived volatile organic compounds or insect host plant preferences. In a field experiment using broccoli as a crop, we combined in a "push-pull" context the oviposition deterrent effect of dimethyl disulfide and the attractive effect of a Chinese cabbage strip enhanced with Z-3-hexenyl-acetate. The push component dimethyl disulfide reduced Delia radicum L. (Diptera: Anthomyiidae) oviposition on broccoli by nearly 30%, and applying Z-3-hexenyl-acetate in the pull component of Chinese cabbage increased it by 40%. Moreover, pest infestation was 40% higher in Chinese cabbage compared to broccoli and parasitism by Trybliographa rapae Westwood (Hymenoptera: Figitidae) was four times higher on this trap plant. In addition, lab experiments confirmed that Chinese cabbage is a more suitable host plant than broccoli for the cabbage root fly. Taken together, our results demonstrate the technical possibility of using a push-pull strategy to manipulate the egg-laying behavior of D. radicum in the field.
Mostrar más [+] Menos [-]Chlordecone consumption estimated by sewage epidemiology approach for health policy assessment Texto completo
2018
Devault, Damien | Amalric, Laurence | Bristeau, Sébastien | Ecologie Systématique et Evolution (ESE) ; AgroParisTech-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) | Bureau de Recherches Géologiques et Minières (BRGM)
International audience | Chlordecone is an organochlorine insecticide that was intensively used in the French West Indies to control the black weevil Cosmopolites sordidus in bananas. Its usage, however, resulted in the widespread pollution of the environment with heavy sanitary and social consequences, leading to population exposure mainly through food. Time-consuming and costly programs have been used to tackle this problem, and this study proposes to use the emerging sewage epidemiology approach to evaluate the current situation and the effect of such programs. The results determine the maximal value of chlordecone consumption, and considering the detection limit of the analytical protocol, the wastewater was found to have undetectable amounts of chlordecone. This value confirms the efficiency of the population protection strategy provided by French sanitary and environmental authorities. It also bolsters the usage of sewage epidemiology in pesticide assessment and relativizes the chlordecone risk compared to other chemicals of lesser concern.
Mostrar más [+] Menos [-]Assessing the ratio of Bacillus spores and vegetative cells by shotgun proteomics Texto completo
2018
Mappa, Charlotte | Pible, Olivier | Armengaud, Jean | Alpha-Bazin, Béatrice | Médicaments et Technologies pour la Santé (MTS) ; Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Service de Pharmacologie et Immunoanalyse (SPI) ; Médicaments et Technologies pour la Santé (MTS) ; Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Laboratoire Innovations technologiques pour la Détection et le Diagnostic (LI2D) ; Service de Pharmacologie et Immunoanalyse (SPI) ; Médicaments et Technologies pour la Santé (MTS) ; Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Médicaments et Technologies pour la Santé (MTS) ; Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Paris-Saclay-Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience
Mostrar más [+] Menos [-]Macroplastic and microplastic contamination assessment of a tropical river (Saigon River, Vietnam) transversed by a developing megacity Texto completo
2018
Lahens, Lisa | Strady, Emilie | Kieu-le, Thuy-chung | Dris, Rachid | Boukerma, Kada | Rinnert, Emmanuel | Gasperi, Johnny | Tassin, Bruno
Both macroplastic and microplastic contamination levels were assessed for the first time in a tropical river estuary system, i.e. the Saigon River, that traverses a developing South East Asian megacity, i.e. Ho Chi Minh City, Vietnam. The analysis of floating debris collected daily on the Nhieu Loc - Thi Nghe canal by the municipal waste management service shows that the plastic mass percentage represents 11-43%, and the land-based plastic debris entering the river was estimated from 0.96 to 19.91 g inhabitant-1 d-1, namely 350 to 7270 g inhabitant-1 yr-1. Microplastics were assessed in the Saigon River and in four urban canals by sampling bulk water for anthropogenic fiber analysis and 300 μm mesh size plankton net exposition for fragment analysis. Fibers and fragments are highly concentrated in this system, respectively 172,000 to 519,000 items m-3 and 10 to 223 items m-3. They were found in various colors and shapes with smallest size and surface classes being predominant. The macroplastics and fragments were mainly made of polyethylene and polypropylene while the anthropogenic fibers were mainly made of polyester. The relation between macroplastic and microplastic concentrations, waste management, population density and water treatment are further discussed.
Mostrar más [+] Menos [-]Oligotrophy as a major driver of mercury bioaccumulation in medium-to high-trophic level consumers: A marine ecosystem-comparative study Texto completo
2018
Chouvelon, Tiphaine | Cresson, Pierre | Bouchoucha, Marc | Brach-papa, Christophe | Bustamante, Paco | Crochet, Sylvette | Marco-miralles, Francoise | Thomas, Bastien | Knoery, Joel
Mercury (Hg) is a global contaminant of environmental concern. Numerous factors influencing its bioaccumulation in marine organisms have already been described at both individual and species levels (e.g., size or age, habitat, trophic level). However, few studies have compared the trophic characteristics of ecosystems to explain underlying mechanisms of differences in Hg bioaccumulation and biomagnification among food webs and systems. The present study aimed at investigating the potential primary role of the trophic status of systems on Hg bioaccumulation and biomagnification in temperate marine food webs, as shown by their medium-to high-trophic level consumers. It used data from samples collected at the shelf-edge (i.e. offshore organisms) in two contrasted ecosystems: the Bay of Biscay in the North-East Atlantic Ocean and the Gulf of Lion in the North-West Mediterranean Sea. Seven species including crustaceans, sharks and teleost fish, previously analysed for their total mercury (T-Hg) concentrations and their stable carbon and nitrogen isotope compositions, were considered for a meta-analysis. In addition, methylated mercury forms (or methyl-mercury, Me-Hg) were analysed. Mediterranean organisms presented systematically lower sizes than Atlantic ones, and lower δ13C and δ15N values, the latter values especially highlighting the more oligotrophic character of Mediterranean waters. Mediterranean individuals also showed significantly higher T-Hg and Me-Hg concentrations. Conversely, Me-Hg/T-Hg ratios were higher than 85% for all species, and quite similar between systems. Finally, the biomagnification power of Hg was different between systems when considering T-Hg, but not when considering Me-Hg, and was not different between the Hg forms within a given system. Overall, the different parameters showed the crucial role of the low primary productivity and its effects rippling through the compared ecosystems in the higher Hg bioaccumulation seen in organisms from oligotrophic Mediterranean waters.
Mostrar más [+] Menos [-]Significance of metallothioneins in differential cadmium accumulation kinetics between two marine fish species Texto completo
2018
Le Croizier, Gael | Lacroix, Camille | Artigaud, Sebastien | Le Floch, Stephane | Raffray, Jean | Penicaud, Virginie | Coquille, Valerie | Autier, Julien | Rouget, Marie-laure | Le Bayon, Nicolas | Lae, Raymond | De Morais, Luis Tito
Impacted marine environments lead to metal accumulation in edible marine fish, ultimately impairing human health. Nevertheless, metal accumulation is highly variable among marine fish species. In addition to ecological features, differences in bioaccumulation can be attributed to species-related physiological processes, which were investigated in two marine fish present in the Canary Current Large Marine Ecosystem (CCLME), where natural and anthropogenic metal exposure occurs. The European sea bass Dicentrarchus labrax and Senegalese sole Solea senegalensis were exposed for two months to two environmentally realistic dietary cadmium (Cd) doses before a depuration period. Organotropism (i.e., Cd repartition between organs) was studied in two storage compartments (the liver and muscle) and in an excretion vector (bile). To better understand the importance of physiological factors, the significance of hepatic metallothionein (MT) concentrations in accumulation and elimination kinetics in the two species was explored. Accumulation was faster in the sea bass muscle and liver, as inferred by earlier Cd increase and a higher accumulation rate. The elimination efficiency was also higher in the sea bass liver compared to sole, as highlighted by greater biliary excretion. In the liver, no induction of MT synthesis was attributed to metal exposure, challenging the relevance of using MT concentration as a biomarker of metal contamination. However, the basal MT pools were always greater in the liver of sea bass than in sole. This species-specific characteristic might have enhanced Cd biliary elimination and relocation to other organs such as muscle through the formation of more Cd/MT complexes. Thus, MT basal concentrations seem to play a key role in the variability observed in terms of metal concentrations in marine fish species.
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