Publications by authors named "Marie-Laure Rouget"

5 Publications

  • Page 1 of 1

A new chemical separation procedure for the determination of rare earth elements and yttrium abundances in carbonates by ICP-MS.

Talanta 2020 Nov 13;219:121244. Epub 2020 Jun 13.

LaTIM (INSERM UMR 1101) Université de Bretagne Occidentale, 22, Avenue C. Desmoulins, 29238, Brest Cedex 3, France.

The determination of rare earth elements (REEs) and Y in carbonates can be complicated by low REE abundances and the presence of significant amounts of Ba resulting in problematic interferences when analysed by ICP-MS. We describe here a novel ion-exchange method using the DGA resin (TODGA), combined with addition of a Tm spike, which allows the separation of the REEs+Y as a whole prior to analysis using an Element XR ICP-MS. This method was validated with results obtained on three different reference carbonate materials (CAL-S, JLs-1 and BEAN, an in-house standard), yielding reproducibility levels better than 3% (RSD) in most cases. This new separation scheme is particularly well suited for carbonate samples having very low REE contents, but could be equally applied to various rock types and organic-rich sample matrices whenever quantitative Ba removal is required.
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http://dx.doi.org/10.1016/j.talanta.2020.121244DOI Listing
November 2020

Metal subcellular partitioning determines excretion pathways and sensitivity to cadmium toxicity in two marine fish species.

Chemosphere 2019 Feb 30;217:754-762. Epub 2018 Oct 30.

Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 CNRS/UBO/IRD/IFREMER, BP 70, 29280 Plouzané, France.

Subcellular cadmium (Cd) partitioning was investigated in the liver of two marine fish species, the European sea bass Dicentrarchus labrax and the Senegalese sole Solea senegalensis, dietary exposed to an environmentally realistic Cd dose for two months followed by a two-month depuration. The two species displayed different handling strategies during the depuration period. Cd was largely bound to detoxifying fractions such as heat stable proteins (HSP) including metallothioneins (MT) in sea bass, while Cd was more linked to sensitive fractions such as organelles in sole. Whole liver concentrations and subcellular partitioning were also determined for essential elements. The greatest impairment of essential metal homeostasis due to Cd exposure was found in sole. These elements followed the Cd partitioning pattern, suggesting that they are involved in antioxidant responses against Cd toxicity. Cd consumption diminished sole growth in terms of body weight, probably due to lipid storage impairment. The contrasting partitioning patterns showed by the two species might imply different pathways for Cd elimination from the liver. In sea bass, MT-bound Cd would be excreted through bile or released into blood, crossing the cell membrane via a protein transporter. In sole, MRG-bound Cd would be sequestered by organelles before being released into the blood via vesicular exocytosis. These distinct strategies in cellular Cd handling in the liver might account for differential sensitivity to Cd toxicity and differential Cd excretion pathways between the two marine fish species.
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http://dx.doi.org/10.1016/j.chemosphere.2018.10.212DOI Listing
February 2019

Significance of metallothioneins in differential cadmium accumulation kinetics between two marine fish species.

Environ Pollut 2018 May;236:462-476

Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 CNRS/UBO/IRD/IFREMER, BP 70, 29280 Plouzané, France.

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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http://dx.doi.org/10.1016/j.envpol.2018.01.002DOI Listing
May 2018

Trophic ecology influence on metal bioaccumulation in marine fish: Inference from stable isotope and fatty acid analyses.

Sci Total Environ 2016 Dec 20;573:83-95. Epub 2016 Aug 20.

Laboratoire des Sciences de l'Environnement Marin (LEMAR), UMR 6539 CNRS/UBO/IRD/IFREMER, BP 70, 29280 Plouzané, France.

The link between trophic ecology and metal accumulation in marine fish species was investigated through a multi-tracers approach combining fatty acid (FA) and stable isotope (SI) analyses on fish from two contrasted sites on the coast of Senegal, one subjected to anthropogenic metal effluents and another one less impacted. The concentrations of thirteen trace metal elements (As, Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Sn, U, and Zn) were measured in fish liver. Individuals from each site were classified into three distinct groups according to their liver FA and muscle SI compositions. Trace element concentrations were tested between groups revealing that bioaccumulation of several metals was clearly dependent on the trophic guild of fish. Furthermore, correlations between individual trophic markers and trace metals gave new insights into the determination of their origin. Fatty acids revealed relationships between the dietary regimes and metal accumulation that were not detected with stable isotopes, possibly due to the trace metal elements analysed in this study. In the region exposed to metallic inputs, the consumption of benthic preys was the main pathway for metal transfer to the fish community while in the unaffected one, pelagic preys represented the main source of metals. Within pelagic sources, metallic transfer to fish depended on phytoplankton taxa on which the food web was based, suggesting that microphytoplankton (i.e., diatoms and dinoflagellates) were a more important source of exposition than nano- and picoplankton. This study confirmed the influence of diet in the metal accumulation of marine fish communities, and proved that FAs are very useful and complementary tools to SIs to link metal accumulation in fish with their trophic ecology.
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http://dx.doi.org/10.1016/j.scitotenv.2016.08.035DOI Listing
December 2016

Stream chemical dynamic and metal accumulation in a temperate watershed affected by agricultural practices (Penzé, NW France).

Rapid Commun Mass Spectrom 2015 Oct;29(19):1795-804

Université de Bretagne Occidentale (Brest), LEMAR UMR-CNRS 6539, I.U.E.M., Place N. Copernic, 29280, Plouzané, France.

Rationale: Understanding the fate of metals in agricultural land is an important issue for agronomic sustainability. This study aimed at quantifying the export/retention of metals in a temperate watershed subject to important manuring activities.

Methods: The chemical composition of the Penzé stream was examined at high resolution during a 1-year study in 2012. After immediate on-site filtration, here demonstrated as necessary to avoid modification of the dissolved-particulate partition, the concentrations of 21 elements were determined using inductively coupled plasma (ICP) optical emission spectrometry and ICP mass spectrometry. This dataset was extended with the local atmospheric deposition of several metals (Cd, Cr, Cu, Pb, Ni and Zn) monitored on a monthly basis.

Results: Two groups were distinguished according to the evolution of the concentrations during floods. Some major cations (Na, Ca, Mg, Sr, K, Ba) and nitrate followed counter-clockwise hysteresis patterns originating from the dilution of the enriched groundwaters by surface waters. Conversely, Al, Fe, Mn, Ti, V, Cr, Co, Ni, Cu, Zn, Cd, Pb and U displayed high dissolved concentration increases at the early stage of floods due to washing out of the enriched soils.

Conclusions: The comparison of stream output fluxes for the two main inputs for the watershed, i.e. atmospheric deposition and manure spreading, indicates that the vast majority of the Cu and Zn (>99 and 96%, respectively), mainly originating from pig manure, is accumulated in the watershed. The accumulation rates for other metals were >60% for Ni and Cr, >75% for As and >90% for Pb and Cd.
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http://dx.doi.org/10.1002/rcm.7282DOI Listing
October 2015