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Determinants of airborne benzene evaporating from fresh crude oils released into seawater
2019
Gjesteland, Ingrid | Hollund, Bjørg Eli | Kirkeleit, Jorunn | Daling, Per Snorre | Sørheim, Kristin Rist
Benzene, toluene, ethylbenzene, xylenes, naphthalene and n-hexane evaporating from a thin oil film was measured for 30 min in a small-scale test system at 2 and 13 °C and the impact of physicochemical properties on airborne benzene with time after bulk oil release was studied. Linear mixed-effects models for airborne benzene in three time periods; first 5, first 15 and last 15 min of sampling, indicated that benzene content in fresh oil, oil group (condensate/light crude oil) and pour point were significant determinants explaining 63–73% of the total variance in the outcome variables. Oils with a high pour point evaporated considerably slower than oils with a low pour point. The mean air concentration of total volatile organic compounds was significatly higher at 13 °C (735 ppm) compared to 2 °C (386 ppm) immediately after release of oil, but at both temperatures the concentration rapidly declined. | acceptedVersion
Afficher plus [+] Moins [-]Airborne concentration and deposition of trace metals and metalloids in an urban area downwind of a manganese alloy plant
2019
Hernández Pellón, Ana María | Fernández Olmo, Ignacio | Universidad de Cantabria
The evaluation of the content of metals and metalloids in particulate matter (PM) and in atmospheric deposition in areas impacted by local industries is essential from an environmental and health risk perspective. In this study, the PM10 levels and atmospheric deposition fluxes of potentially toxic metals and metalloids were quantified at three urban sites of the Cantabrian region (northern Spain), located at different distances downwind of a Mn alloy plant. The content of Mn, V, Fe, Ni, Cu, Zn, As, Mo, Cd, Sb and Pb in PM10 and in the water-soluble and insoluble fractions of the deposition was determined by ICP-MS. Among the studied elements, the highest concentrations in PM10 and deposition rates were found for Mn, Fe, Zn and Pb, associated with the Mn alloy industry, and for Cu, related to non-exhaust traffic emissions. The levels of Mn, Fe, Zn and Pb in PM10 were higher in autumn, when the most frequent winds blow from the S-SW, whereas their highest deposition rates were found in winter and autumn, which are characterized by high monthly average precipitations. The water-soluble fraction of the atmospheric deposition of most metals increased with distance from the Mn alloy plant. The highest water-soluble fractions were found for Ni (72%), Zn (62%), Cu (60%) and Mn (49%). These results will be useful for the health risk assessment of the metal exposure associated with Mn alloy plants, as well as for the evaluation of the metal burden to soil, water and ecosystems related to this industrial activity. | This work was financially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the CTM2013-43904R Project. Ana Hernández-Pellón would like to thank the Ministry of Economy and Competitiveness (MINECO) for the FPI grant awarded, reference number BES-2014-068790.
Afficher plus [+] Moins [-]From mechanical to chemical impact of anchoring in seagrasses: the premises of anthropogenic patch generation in Posidonia oceanica meadows
2016
Abadie, Arnaud | Lejeune, Pierre | Pergent, Gérard | Gobert, Sylvie | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Intensive anchoring of leisure boats in seagrass meadows leads to mechanical damages. This anthropogenic impact creates bare mat patches that are not easily recolonized by the plant. Several tools are used to study human impacts on the structure of seagrass meadows but they are not able to assess the indirect and long term implication of mechanical destruction. We chose to investigate the possible changes in the substrate chemistry given contrasted boat impacts. Our observations show that hydrogen sulfide concentrations remain high at 15 and 20 m depth (42.6 µM and 18.8 µM) several months after the highest period of anchoring during the summer. Moreover, our multidisciplinary study reveals that anchoring impacts of large boats at 15 and 20 m depth can potentially change the seascape structure. By taking into account both structural and chemical assessments, different managing strategies must be applied for coastal areas under anthropogenic pressures. | STARE-CAPMED
Afficher plus [+] Moins [-]Environmental harm assessment of a wastewater discharge from Hammerfest LNG: A study with biomarkers in mussels (Mytilus sp.) and Atlantic cod (Gadus morhua)
2013
Beyer, Jonny | Aarab, Nadia | Tandberg, Anne Helene Solberg | Ingvarsdottir, Anna | Bamber, Shaw Duncan | Børseth, Jan Fredrik | Camus, Lionel | Velvin, Roger
Biologically treated wastewater (WW) from the Hammerfest LNG (liquefied natural gas) plant is discharged to the sea. A study using biomarkers in mussels and Atlantic cod was performed to examine whether this discharge meets a zero harmful emission requirement. Caging of mussels close to the outfall and exposure of mussels and fish to WW in the laboratory were conducted, and a suite of contaminant responsive markers was assessed in exposed animals. In mussels the markers included chemical contaminant levels, haemocyte lysosomal instability and nucleus integrity, cellular energy allocation, digestive gland and gonad histopathology and shell-opening behaviour. In fish, biliary PAH metabolites and gill histopathology biomarkers were measured. A consistent cause-effect relationship between WW treatments and markers measured in test animals was not found. The results therefore indicate that the WW emission is unlikely to represent a significant stress factor for the local marine environment under the conditions studied. | acceptedVersion
Afficher plus [+] Moins [-]Variation patterns in individual fish responses to chemical stress among estuaries, seasons and genders: the case of the European flounder (Platichthys flesus) in the Bay of Biscay
2013
Laroche , Jean (Université Européenne de BretagneInstitut Universitaire Européen de la MerCentre National de la Recherche ScientifiqueInstitut Français de Recherche pour l'Exploitation de la MerLaboratoire des Sciences de l’Environnement Marin LEMARUBO,Université de Bretagne Occidentale,Brest (FRA)Institut Français de Recherche pour l'Exploitation de la Mer, PlouzanéPlouzané(France).) | Gauthier , Olivier (Laboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la MerUniversité Européenne de BretagneCentre National de la Recherche ScientifiqueUBO,Université de Bretagne Occidentale,Brest (FRA)Institut Français de Recherche pour l'Exploitation de la Mer(France). UMR 6539 ) | Quiniou , Louis (Laboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la MerUniversité Européenne de BretagneUBO,Université de Bretagne Occidentale,Brest (FRA)Institut Français de Recherche pour l'Exploitation de la Mer, Plouzané(France). UMR6539) | Devaux , Alain (INRA (France). ) | Bony , Sylvie (INRA , Marcy-L'Étoile (France). UMR 1233 Mycotoxines et Toxicologie Comparée des Xénobiotiques) | Evrard , Esterine (Centre de Recherches Européennes de Rennes(France).) | Cachot , Jérôme (Université de Bordeaux, Talence(France).) | Cherel , Yan (INRA , Nantes (France). UMR 0703 Physiopathologie animale et biothérapies du muscle et du système nerveux) | Larcher , Thibaut (INRA , Nantes (France). UMR 0703 Physiopathologie animale et biothérapies du muscle et du système nerveux) | Riso , Ricardo (Laboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la MerUniversité Européenne de BretagneUBO,Université de Bretagne Occidentale,Brest (FRA)Institut Français de Recherche pour l'Exploitation de la Mer, Plouzané(France). UMR 6539) | Pichereau , Vianney (Laboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la MerUniversité Européenne de BretagneInstitut Français de Recherche pour l'Exploitation de la MerUBO,Université de Bretagne Occidentale,Brest (FRA), Plouzané(France). UMR 6539) | Devier , Marie-Hélène (Université de Bordeaux(France). EPOC UMR 5805) | Budzinski , Hélène (Université Bordeaux 1, Talence(France). EPOC UMR 5805)
The objective was to describe and model varia- tion patterns in individual fish responses to contaminants among estuaries, season and gender. Two hundred twenty- seven adult European flounders were collected in two sea- sons (winter and summer) in four estuaries along the Bay of Biscay (South West France), focusing on a pristine system (the Ster), vs. three estuaries displaying contrasted levels of contaminants (the Vilaine, Loire and Gironde). Twenty-three variables were measured by fish, considering the load of contaminants (liver metals, liver and muscle persistent organic pollutants, muscle polycyclic aromatic hydrocar- bons); the gene expression (Cyt C oxydase, ATPase, BHMT, Cyt P450 1A1, ferritin); the blood genotoxicity (Comet test); and liver histology (foci of cellular alteration–tumour, steatosis, inflammation, abnormal glycogen storage). Ca- nonical redundancy analysis (RDA) was used to model these variables using gender, season and estuary of origin as explanatory variables. The results underlined the homo- geneity of fish responses within the pristine site (Ster) and more important seasonal variability within the three contam- inated systems. The complete model RDA was significant and explained 35 % of total variance. Estuary and season respectively explained 30 and 5 % of the total independent variation components, whilst gender was not a significant factor. The first axis of the RDA explains nearly 27 % of the total variance and mostly represents a gradient of contami- nation. The links between the load of contaminants, the expression of several genes and the biomarkers were ana- lysed considering different levels of chemical stress and a possible multi-stress, particularly in the Vilaine estuary.
Afficher plus [+] Moins [-]The beta-receptor blocker metoprolol alters detoxification processes in the non-target organism Dreissena polymorpha
2010
Contardo-Jara, Valeska | Pflugmacher, Stephan | Nutzmann, Gunnar | Kloas, Werner | Wiegand, Claudia
Due to increasing amounts of pharmaceutically active compounds (PhACs) in the aquatic environment, their largely unknown effects to non-target organisms need to be assessed. This study examined physiological changes in the freshwater mussel Dreissena polymorpha exposed to increasing concentrations (0.534, 5.34, 53.4 and 534 mg L1) of the b-blocker metoprolol in a flow-through system for seven days.The two lower concentrations represent the environmentally relevant range. Surprisingly, metallothionein mRNA was immediately up-regulated in all treatments. For the two higher concentrations mRNA up-regulation in gills was found for P-glycoprotein after one day, and after four days for pi class glutathione S-transferase, demonstrating elimination and biotransformation processes, respectively. Additionally, catalase and superoxide dismutase were up-regulated in the digestive gland indicating oxidative stress. In all treated mussels a significant up-regulation of heat shock protein mRNA was observed in gills after four days, which suggests protein damage and the requirement for repair processes. Metoprolol was 20-fold bioaccumulated for environmentally relevant concentrations. | International audience
Afficher plus [+] Moins [-]Tracing sewage and natural freshwater input in a Northwest Mediterranean bay: Evidence obtained from isotopic ratios in marine organisms
2010
Lassauque, Julien | Lepoint, Gilles | Thibaut, T. | Francour, Patrice | Meinesz, A. | Université de Sophia Antipolis | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège
peer reviewed | Elemental carbon and nitrogen levels and isotope ratios were assessed in different biological compartments of a Northwest (NW) Mediterranean bay to trace the various sources of nutrient input from natural (river runoffs) and anthropogenic (harbor outflows, fish farms and urban sewage outfall) sources. Samples from transplanted mussels and natural sea grass communities (Posidonia oceanica leaves and epiphytes) were harvested from different locations throughout the bay during the touristic summer and rainy seasons. The results from the nitrogen analysis revealed that sewage and harbor outflow promote higher nitrogen levels, enrichment of N-15 in the tissues, and a higher seasonal variability in sea grass and epiphytes. In mussel tissues, the delta N-15 was also influenced by sewage and harbor outflow, whereas delta C-13 was influenced by terrestrial inputs. These results suggest that natural and anthropogenic nutrient inputs have a temporary and localized influence and affect the sensitivity of natural isotopic ratios to changes in hydrologic conditions, especially to rain and tourism. (C) 2010 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Bioactivity of MWCNT in conidia of entomopathogenic fungus Isaria fumosorosea
Anna Gorczyca | Marek Kasprowicz | Tadeusz Lemek
The bioactivity of three kinds of multi-walled carbon nanotubes (MWCNT) towards the conidia of entomopathogenic fungus Isaria fumosorosea was examined in an in vitro study. Commercial—raw and functionalized—carboxylated MWCNT were applied. A fungal conidia suspension was placed in contact with dispersed MWCNT over different time-periods. After contact with the nanomaterial, the conidia were cultured on dishes and both the linear vegetative mycelium growth and the sporulation and germination of the spores derived from the culture were investigated. Also, the pathogenicity of the conidia after contact with MWCNT was examined in relation to test larvae. No fungistatic activity of MWCNT relative to I. fumosorosea conidia was demonstrated. Conidia contact with MWCNT resulted in the following changes in vital processes in the subsequent culture compared to the control standard culture: (1) raw MWCNT limited mycelium inoculation, but the growth rate observed later in the log-phase was more intense; (2) after 24-h conidia contact with all MWCNT types, the mycelium sporulated the most intensively; longer contact resulted in sporulation process limitation. Germination of conidia after contact with the MWCNT was not significantly modified. Raw MWCNT potentiated conidia pathogenicity towards test insects. It was observed that carboxylation of MWCNT reduces the bioactivity of this nanomaterial towards the investigated conidia. | multi-walled carbon nanotubes, carboxylation, Isaria fumosorosea, conidia, culture, pathogenicity | 25 | 1-11
Afficher plus [+] Moins [-]Quantitative and Qualitative Changes of Precipitation Input to the Ojców National Park (South Poland) during 1997–1999
Stanisław Małek
Changes of the qualitative and quantitative features of snow and rain during the winter and the vegetation period, respectively, were studied during three years (1997–1999). The sites were located on Chełmova Góra Mt. in the Ojców National Park (South Poland), which is one of the most polluted areas in Poland. Standard methods of measuring bulk precipitation were used according to the ICP Forest Manual. One plot was near the summit part (OPN2), and the other plot was in the lower part close to the foot (OPN5) of the Chełmowa Góra Mt. The total amount of Ca decreased during the study period, while NO3 − and SO4 −2 decreased only in the vegetation period. During the winter period the snow carried high amounts of Cl−, NO3 −, SO4 −2, Na, Mg, and Ca. A decrease in pH was noticed during the winter periods, whereas an increase in pH was found during the vegetation period. Higher element concentrations were always found in the upper plot compared to the lower situated plot. This indicated that the upper and more exposed parts of the mountains in the Park were under higher pollution stress. | bulk, snow, precipitation, main anions and cations, Ojców National Park, Poland | 0 | 505-510 | 1-4
Afficher plus [+] Moins [-]Antimicrobial resistance and the presence of extended-spectrum beta-lactamase genes in Escherichia coli isolated from the environment of horse riding centers
Katarzyna Wolny-Koładka | Anna Lenart-Boroń
The aim of the study was to determine the antimicrobial resistance profile and the occurrence of extended-spectrum beta-lactamase genes and to analyze the genetic diversity of Escherichia coli strains isolated from the environment of horse riding centers. The study was conducted using E. coli strains isolated from the air, manure, and horse nostril swabs in three horse riding centers differing in the system of horse keeping-stable (OJK Pegaz and KJK Szary) and free-range (SKH Nielepice). Resistance to antibiotics was determined using the disk-diffusion method, and the PCR technique was employed to detect the extended-spectrum β-lactamase (ESBL) genes, while the genetic diversity of strains was assessed by rep-PCR. A total of 200 strains were collected during the 2-year study, with the majority isolated from KJK Szary, while the smallest number was obtained from SKH Nielepice. The strains were mostly resistant to ampicillin, aztreonam, and ticarcillin. The tested strains were most frequently resistant to one or two antibiotics, with a maximum of ten antimicrobials at the same time. Two multidrug-resistant (MDR) strains were detected in OJK Pegaz while in KJK Szary there were two MDR and one extensively drug-resistant (XDR) strain. The ESBL mechanism was most frequently observed in OJK Pegaz (20.31% of strains) followed by KJK Szary (15.53% of strains) and SKH Nielepice (15.15% of strains). Among the ESBL-determining genes, only blaTEM and blaCTXM-9 were detected-blaTEM was mostly found in KJK Szary (53.40% of strains), while the second detected gene-blaCTXM-9-was most frequent in SKH Nielepice (6.06% of strains). The rep-PCR genotyping showed high variation among the analyzed strains, whereas its degree differed between the studied facilities, indicating that the type of horse keeping (stable vs. free-range) affects the genetic diversity of the E. coli strains. Having regard to the fact that the tested strains of E. coli were derived from non-hospitalized horses that were not treated pharmacologically, we can assume that the observed antimicrobial resistance may be of both-natural origin, i.e., not the result of the selection pressure, and acquired, the source of which could be people present in the horse riding facilities, the remaining horses which were not included in the study, and air, as well as water, fodder, and litter of the animals. Therefore, it can be concluded that the studied horses are the source of resistant E. coli and it is reasonable to continue monitoring the changes in antimicrobial resistance in those bacteria. | Antibiotics; Antimicrobial resistance; Escherichia coli; Extended-spectrum beta-lactamases, horses | 30 | 21789-21800 | 22
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