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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.
اظهر المزيد [+] اقل [-]Histopathological lesions and DNA adducts in the liver of European 1 flounder (Platichthysflesus) collected in the Seine estuary versus two reference estuarine systems on the FrenchAtlantic coast
2013
Cachot , Jérôme(auteur de correspondance) (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) | Pfohl-Leszkowicz , Annie (Université de Toulouse CNRS, Castanet-Tolosan(France).) | Laroche , Jean (Université de BrestLaboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la Mer, BrestPlouzané(France). UMR 6539) | Quiniou , Louis (Université de BrestLaboratoire des Sciences de l’Environnement Marin LEMARInstitut Universitaire Européen de la Mer, BrestPlouzané(France). UMR 6539) | Morin , Jocelyne (Institut Français de Recherche pour l'Exploitation de la Mer, Port en bessin(France).) | Schmitz , Julien (Institut Français du Pétrole, Rueil-Malmaison(France).) | Burgeot , Thierry (Institut Français de Recherche pour l'Exploitation de la Mer, Nantes(France). Département Polluants chimiques) | Pottier , Didier (Université de Caen Basse Normandie, Caen(France). UR ABTE EA 4651)
Arsenic mobility controlled by solid calcium arsenates: A case study in Mexico showcasing a potentially widespread environmental problem
2013
Martínez-Villegas, Nadia | Briones-Gallardo, Roberto | Ramos-Leal, José A. | Avalos-Borja, Miguel | Castañón-Sandoval, Alan D. | Razo-Flores, Elías | Villalobos, Mario
An As-contaminated perched aquifer under an urban area affected by mining was studied over a year to determine the contamination source species and the mechanism of As mobilization. Results show that the dissolution of calcium arsenates in residues disposed on an inactive smelter has caused high levels of As pollution in the adjoining downgradient 6-km perched aquifer, reaching up to 158 mg/L of dissolved As, and releasing a total of ca. 7.5 tons of As in a year. Furthermore, free calcium ion availability was found to control As mobility in the aquifer through the diagenetic precipitation of calcium arsenates (Ca5H2(AsO4)4·cH2O) preventing further mobilization of As. Results shown here represent a model for understanding a highly underreported mechanism of retention of arsenate species likely to dominate in calcium-rich environments, such as those in calcareous sediments and soils, where the commonly reported mechanism of adsorption to iron(III) oxyhydroxides is not the dominant process.
اظهر المزيد [+] اقل [-]Photochemical trajectory modeling of ozone concentrations in Hong Kong
2013
Cheng, H.R. | Saunders, S.M. | Guo, H. | Louie, P.K.K. | Jiang, F.
In this study, tropical cyclones over the East and South China Seas were found to be the most predominant weather conditions associated with the occurrence of high ozone (O3) episodes in Hong Kong in 2005–2009. A photochemical trajectory model coupled with Master Chemical Mechanism (MCM) was adapted to simulate the O3 concentrations during two O3 pollution episodes. The results agreed well with the observed data. A representative backward air mass trajectory was used to determine the contribution of each volatile organic compound (VOC) to the O3 levels. After taking into account both reactivity and mass emission of each VOC, 10 species were found to be the key O3 precursors in Hong Kong. Further analysis identified solvent related products accounting for 70% of the modeled O3 concentration in Hong Kong. The results highlight the importance of considering together reactivity and source sector emissions in developing targeted VOC reduction for O3 abatement strategies.
اظهر المزيد [+] اقل [-]Mercury concentrations in human placenta, umbilical cord, cord blood and amniotic fluid and their relations with body parameters of newborns
2013
Kozikowska, Iwona | Binkowski, Łukasz J. | Szczepańska, Katarzyna | Sławska, Helena | Miszczuk, Katarzyna | Śliwińska, Magdalena | Łaciak, Tomasz | Stawarz, Robert
Studies were conducted on samples taken from giving birth women (n = 40) living in Poland, representing three age groups: 19–25, 26–30 and 31–38 years old. Mercury concentrations were measured with CV-AAS in placenta, umbilical cord, cord blood and amniotic fluid.The placentas weight did not exceed the 750 g value and was heavier than 310 g. Mean values of Hg concentrations in blood, placenta and umbilical cord were similar (c.a. 9 μg/g). High levels of mercury were noted in cord blood which in 75% of all observations exceeded (up to 17 μg/L) the safe dose set by US EPA (5.8 μg/L). No statistically significant differences in medium level of Hg in all the studied tissues among age groups of women were observed. Positive correlations between Hg concentrations in placenta and umbilical cord and cord blood were revealed as well as some negative ones between mercury concentrations and pregnancy parameters.
اظهر المزيد [+] اقل [-]Levels of metals in blood samples from Mallards (Anas platyrhynchos) from urban areas in Poland
2013
Binkowski, Łukasz J. | Meissner, Włodzimierz
In this paper we present the studies conducted on blood samples taken from Mallards (Anas platyrhynchos). Birds were captured for ringing purposes (n = 43) in two small and two big towns (including highly urbanized areas). For comparison samples of blood from birds shot on fish ponds were used (n = 26). Based on the body mass all sampled individuals can be assessed as being in good condition. Levels of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) in blood samples were measured with AAS. Concentrations of metals did not differ statistically between sexes and made up a following order: Fe > Zn > Cu > Cr ≈ Ni > Pb > Cd. Mallards from towns revealed lower concentrations of Zn and Cu but higher concentration of Fe. There was no difference in exposition to Pb between birds from towns and fish ponds.
اظهر المزيد [+] اقل [-]Artifact weathering, anthropogenic microparticles and lead contamination in urban soils at former demolition sites, Detroit, Michigan
2013
Howard, Jeffrey L. | Dubay, Brian R. | Daniels, W Lee
A chronological sequence of urban soils 3–92 years old was studied to determine the effects of time on morphogenesis, artifact weathering, and the geochemical partitioning of Pb. Key chronofunctions determined are an increase in ˆA horizon Development Index (defined herein based on soil color) and water-soluble Pb, and a decrease in pH and C/N, with increasing soil age. Key artifact weathering reactions are: 1) portlandite in mortar altered to calcite, 2) ferrite in wrought-iron altered to ferrihydrite and goethite, and 3) carbonaceous materials altered to water-soluble organic substances. Mortar and wrought-iron were found to be Pb-bearing, but weather to produce immobilizing agents. Hence, they are both a source and a sink for Pb. The origin and mobilization of water-soluble Pb is complex and probably includes microbial extracellular polymeric substances, biodegraded soil organic matter, and solubilized organic substances derived from carbonaceous anthropogenic microparticles (soot, char and coal-related wastes).
اظهر المزيد [+] اقل [-]Tracing decadal environmental change in ombrotrophic bogs using diatoms from herbarium collections and transfer functions
2013
Poulíčková, Aloisie | Hájková, Petra | Kintrová, Kateřina | Bat'ková, Romana | Czudková, Markéta | Hájek, Michal
Central European mountain bogs, among the most valuable and threatened of habitats, were exposed to intensive human impact during the 20th century. We reconstructed the subrecent water chemistry and water-table depths using diatom based transfer functions calibrated from modern sampling. Herbarium Sphagnum specimens collected during the period 1918–1998 were used as a source of historic diatom samples. We classified samples into hummocks and hollows according to the identity of dominant Sphagnum species, to reduce bias caused by uneven sampling of particular microhabitats. Our results provide clear evidence for bog pollution by grazing during the period 1918–1947 and by undocumented aerial liming in the early 90-ies. We advocate use of herbarized epibryon as a source of information on subrecent conditions in recently polluted mires.
اظهر المزيد [+] اقل [-]Ionic profile of honey as a potential indicator of botanical origin and global environmental pollution
2013
Fermo, Paola | Beretta, Giangiacomo | Maffei Facino, Roberto | Gelmini, Fabrizio | Piazzalunga, Andrea
Aim of this study was to determine by Ion Chromatography ions (Na+, Ca++, Mg++, NH4+, Cl−, Br−, SO42−, NO3−, PO43−) in honeys (honeydew and floral nectar honeys) from different Italian Regions and from countries of the Western Balkan area. The compositional data were processed by multivariate analysis (PCA and HCA). Arboreal honeydew honeys from the Western Balkans had higher concentrations (from two to three times) of some environmental pollutants (Br−, SO42− and PO43− contents), due to industrial and agricultural activities, than those from Italian regions. The cationic profiles were very similar in both groups. Multivariate analysis indicated a clear difference between nectar honeys and arboreal/honeydew honeys (recognition of the botanical origin). These findings point to the potential of ionic constituents of honey as indicators of environmental pollution, botanical origin and authenticity.
اظهر المزيد [+] اقل [-]Influence of age, sex and breeding status on mercury accumulation patterns in the wandering albatross Diomedea exulans
2013
Tavares, S. | Xavier, J.C. | Phillips, R.A. | Pereira, M.E. | Pardal, M.A.
Although mercury bio-amplifies through the food chain and accumulates in top predators, mercury concentrations in tissues of the wandering albatross are greater than in any other vertebrate, including closely related species. In order to explore the alternative explanations for this pattern, we measured total mercury concentrations in feathers, plasma and blood cells of wandering albatrosses of known age, sex and breeding status sampled at South Georgia. Mercury concentrations were low in feathers and blood components of chicks, and higher in the feathers of young pre-breeders than in feathers or blood of older pre-breeders and breeding adults. There was no effect of sex on mercury concentrations in the feathers of pre-breeders or breeding adults, whereas levels were significantly higher in blood cells of breeding females than males. The high feather mercury concentrations of young pre-breeders compared with older birds suggest an increase in moult frequency as birds approach maturity.
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