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Spatial and sex differences in mercury contamination of skuas in the Southern Ocean
2022
Mills, William, | Ibañez, Andrés, | Bustamante, Paco | Carneiro, Ana, | Bearhop, Stuart | Cherel, Yves | Mariano-Jelicich, Rocío | Mcgill, Rona, | Montalti, Diego | Votier, Stephen, | Phillips, Richard,
Antarctic marine ecosystems are often considered to be pristine environments, yet wildlife in the polar regions may still be exposed to high levels of environmental contaminants. Here, we measured total mercury (THg) concentrations in blood samples from adult brown skuas Stercorarius antarcticus lonnbergi (n = 82) from three breeding colonies south of the Antarctic Polar Front in the Southern Ocean (southwest Atlantic region): (i) Bahía Esperanza/Hope Bay, Antarctic Peninsula; (ii) Signy Island, South Orkney Islands; and, (iii) Bird Island, South Georgia. Blood THg concentrations increased from the Antarctic Peninsula towards the Antarctic Polar Front, such that Hg contamination was lowest at Bahía Esperanza/Hope Bay (mean ± SD, 0.95 ± 0.45 µg g-1 dw), intermediate at Signy Island (3.42 ± 2.29 µg g-1 dw) and highest at Bird Island (4.47 ± 1.10 µg g-1 dw). Blood THg concentrations also showed a weak positive correlation with δ15N values, likely reflecting the biomagnification process. Males had higher Hg burdens than females, which may reflect deposition of Hg into eggs by females or potentially differences in their trophic ecology. These data provide important insights into intraspecific variation in contamination and the geographic transfer of Hg to seabirds in the Southern Ocean.
Show more [+] Less [-]Vulnerability and tolerance to nickel of periphytic biofilm harvested in summer and winter
2022
Laderriere, Vincent | Morin, Soizic | Eon, Mélissa | Fortin, Claude | Centre Eau Terre Environnement [Québec] (INRS - ETE) ; Institut National de la Recherche Scientifique [Québec] (INRS) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Nunavik
International audience | Metals are naturally present in freshwater ecosystems but anthropogenic activities like mining operations represent a long-standing concern. Metals released into aquatic environments may affect microbial communities such as periphytic biofilm, which plays a key role as a primary producer in stream ecosystems. Using two 28-day microcosm studies involving two different photoperiods (light/dark cycle of 16/8 vs 8/16), the present study assessed the effects of four increasing nickel (Ni) concentrations (0-6 mu M) on two natural biofilm communities collected at different seasons (summer and winter). The two communities were characterized by different structural profiles and showed significant differences in Ni accumulated content for each treatment. For instance, the biofilm metal content was four times higher in the case of summer biofilm at the highest Ni treatment and after 28 days of exposure. Biomarkers examined targeted both heterotrophic and autotrophic organisms. For heterotrophs, the 8-glucosidase and 8-glucosaminidase showed no marked effects of Ni exposure and were globally similar between the two communities suggesting low toxicity. However, the photosynthetic yield confirmed the toxicity of Ni on autotrophs with maximum inhibition of 81 +/- 7% and 60 +/- 1% respectively for the summer and winter biofilms. Furthermore, biofilms previously exposed to the highest long-term Ni con-centration ([Ni2+] = 6 mu M) revealed no acute effects in subsequent toxicity based on the PSII yield, suggesting a tolerance acquisition by the phototrophic community. Taken together, the results suggest that the biofilm response to Ni exposure was dependent of the function considered and that descriptors such as biofilm metal content could be seasonally dependent, information of great importance in a context of biomonitoring.
Show more [+] Less [-]Elasmobranchs as bioindicators of pollution in the marine environment
2022
Alves, Luís M.F. | Lemos, Marco F.L. | Cabral, Henrique | Novais, Sara | Marine and Environmental Sciences Centre [Portugal] (MARE) ; Instituto Universitário de Ciências Psicológicas, Sociais e da Vida = University Institute of Psychological, Social and Life Sciences (ISPA) | Ecosystèmes aquatiques et changements globaux (UR EABX) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
International audience | Bioindicator species are increasingly valuable in environmental pollution monitoring, and elasmobranch species include many suitable candidates for that role. By measuring contaminants and employing biomarkers of effect inrelevant elasmobranch species, scientists may gain important insights about the impacts of pollution in marine ecosystems. This review compiles biomarkers applied in elasmobranchs to assess the effect of pollutants (e.g.,metals, persistent organic pollutants, and plastics), and the environmental changes induced by anthropogenic activities (e.g., shifts in marine temperature, pH, and oxygenation). Over 30 biomarkers measured in more than12 species were examined, including biotransformation biomarkers (e.g., cytochrome P450 1A), oxidative stress-related biomarkers (e.g., superoxide anion, lipid peroxidation, catalase, and vitamins), stress proteins (e.g., heatshock protein 70), reproductive and endocrine biomarkers (e.g., vitellogenin), osmoregulation biomarkers (e.g., trimethylamine N-oxide, Na+/K+-ATPase, and plasma ions), energetic and neurotoxic biomarkers (e.g., lactatedehydrogenase, lactate, and cholinesterases), and histopathological and morphologic biomarkers (e.g., tissue lesions and gross indices).
Show more [+] Less [-]Occurrence, contamination level and ecological risk assessment of dissolved and particulate trace elements in rivers entering the southwestern Mediterranean Sea
2022
Benhalima, Moustafa | Boulahdid, Mostefa | Guendouzi, Yassine | Radakovitch, Olivier | Aroua, Mohamed | Fowler, Scott, W | Ambrosi, Jean-Paul | Angeletti, Bernard | Ecole Nationale Supérieure des Sciences de la Mer et de l'Aménagement du Littoral (ESSMAL) | CENTRE UNIVERSITAIRE DE TIPAZA OUED MERZOUG TIPAZA DZA ; 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) | Laboratoire de recherche sur les transferts des radionucléides dans les écosystèmes aquatiques (IRSN/PSE-ENV/SRTE/LRTA) ; Service de recherche sur les transferts et les effets des radionucléides sur les écosystèmes (IRSN/PSE-ENV/SRTE) ; Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN) | Stony Brook University [SUNY] (SBU) ; State University of New York (SUNY) | Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Directorate General for Scientific Research and Technological Development (DGRSDT)Algeria and French program METMAR-MERMEX as part of the PHCTASSILI project.
International audience | Metal pollution in rivers should not be overlooked before their entry into the sea. However, there are few studies for estimating such contamination in rivers entering the Algerian coastal waters. Semimonthly quantification of dissolved and particulate metals, near the mouths of two industrial-tainted rivers, El Harrach and Mazafran rivers, was carried out during a period of one year. All the trace metals analyzed are originating from anthropogenic sources (EF > 1.5), with higher contamination of dissolved Pb, Cd, Zn and Ni and a slight degree of contamination of particulate Cu and Zn (0 < I geo < 1). Particulate metals show a stable complex with the particulate phase (e.g. 2 < LogK d < 6). The risk assessment results indicate that particulate Pb and Zn have a 33% likelihood of toxicity for adverse biological effects. A significant toxicity effect (ΣTUi >4) of the combined particulate metals (Pb, Cd, Cu, Zn, Cr, Ni and As) was primarily due to the higher particulate Cd, Zn, and Cr availability.
Show more [+] Less [-]Screening of metallic pollution in complex environmental samples through a transcriptomic fingerprint method
2022
Cregut, Mickael | Hua, Anna | Jouanneau, Sulivan | Assaf, Ali | Cordella, Christophe, B Y | Thouand, Gérald | Durand, Marie-José | Traitement Eau Air Métrologie (GEPEA-TEAM) ; Laboratoire de génie des procédés - environnement - agroalimentaire (GEPEA) ; École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique) ; Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST) ; Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - Institut Universitaire de Technologie Saint-Nazaire (Nantes Univ - IUT Saint-Nazaire) ; Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique) ; Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST) ; Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - Institut Universitaire de Technologie Saint-Nazaire (Nantes Univ - IUT Saint-Nazaire) ; Nantes Université - pôle Sciences et technologie ; Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ) | Physiologie de la Nutrition et du Comportement Alimentaire (PNCA (UMR 0914)) ; AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | French Ministry of Research | General Council of Vendee | City of La Roche sur Yon | MATIERES Research program, Conseil Régional des Pays de la Loire
International audience | Characterizing waste ecotoxicity is laborious because of both the undefined nature of environmental samples and the diversity of contaminants that can be present. With regard to these limitations, traditional approaches do not provide information about the nature of the pollution encountered. To improve such assessments, a fluorescent library of 1870 transcriptomic reporters from Escherichia coli K12 MG1655 was used to report the ecotoxic status of environmental samples. The reliability of the approach was evaluated with 6 metallic pollutants (As, Cu, Cd, Hg, Pb, Zn) used alone and in mixture in pure and complex matrices. A total of 18 synthetic samples were used to characterize the specificity of the resulting metallic contamination fingerprints. Metallic contamination impacted 4.5 to 10.2% of the whole transcriptomic fingerprint of E. coli. The analysis revealed that a subset of 175 transcriptomic reporters is sufficient to characterize metallic contamination, regardless of the nature of the sample. A statistical model distinguished patterns due to metallic contamination and provided information about the level of toxicity with 93 to 98% confidence. The use of the transcriptomic assessment was validated for 17 complex matrices with various toxicities and metal contaminants, such as activated sludge, wastewater effluent, soil, wood and river water. The presence of metals and their associated toxicity, which seems linked to their bioavailabilities, were thereby determined. This method constitutes a possible tool to screen unknown complex samples for their metallic status and identify those for which a deeper characterization must be achieved by the use of traditional biosensors and analytical methods.
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