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Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate 全文
2008
Labanowski, J. | Monna, F. | Bermond, A. | Cambier, P. | Fernández, C. | Lamy, I. | Oort, F van
Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate 全文
2008
Labanowski, J. | Monna, F. | Bermond, A. | Cambier, P. | Fernández, C. | Lamy, I. | Oort, F van
Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (QM1) and less labile (QM2). In citrate extractions, total extractability (QM1 + QM2) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar QM1/QM2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth. Kinetically defined metal fractions mimic mobility aspects of heavy metals.
显示更多 [+] 显示较少 [-]Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate. 全文
2008
Labanowski , Jérome (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Monna , Fabrice (Centre National de la Recherche Scientifique, Dijon(France). Univ. de Bourgogne Centre des Sciences de la Terre) | Bermond , Alain (INRA , Thiverval-Grignon (France). UMR 1091 Environnement et Grandes Cultures) | Cambier , Philippe (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Fernandez , Christelle (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Lamy , Isabelle (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Van Oort , Folkert (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés)
Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (QM1) and less labile (QM2). In citrate extractions, total extractability (QM1 + QM2) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar QM1/QM2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth.
显示更多 [+] 显示较少 [-]Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate. 全文
2008
Labanowski, Jérôme | Monna, Fabrice | Bermond, Alain | Cambier, Philippe | Fernandez, Christelle | Lamy, Isabelle | van Oort, Folkert | Physicochimie et Ecotoxicologie des SolS d'Agrosystèmes Contaminés (PESSAC) ; Institut National de la Recherche Agronomique (INRA) | Archéologies, Cultures et Sociétés (ACS) ; Ministère de la Culture et de la Communication (MCC)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Biogéosciences [UMR 5561] [Dijon] ; Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech
Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (QM1) and less labile (QM2). In citrate extractions, total extractability (QM1 + QM2) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar QM1/QM2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth.
显示更多 [+] 显示较少 [-]Kinetic extractions to assess mobilization of Zn, Pb, Cu, and Cd in a metal-contaminated soil: EDTA vs. citrate. 全文
2008
Labanowski, Jérome | Monna, Fabrice | Bermond, Alain | Cambier, Philippe | Fernandez, Christelle | Lamy, Isabelle | Van Oort, Folkert
Kinetic EDTA and citrate extractions were used to mimic metal mobilization in a soil contaminated by metallurgical fallout. Modeling of metal removal rates vs. time distinguished two metal pools: readily labile (QM1) and less labile (QM2). In citrate extractions, total extractability (QM1 + QM2) of Zn and Cd was proportionally higher than for Pb and Cu. Proportions of Pb and Cu extracted with EDTA were three times higher than when using citrate. We observed similar QM1/QM2 ratios for Zn and Cu regardless of the extractant, suggesting comparable binding energies to soil constituents. However, for Pb and Cd, more heterogeneous binding energies were hypothesized to explain different kinetic extraction behaviors. Proportions of citrate-labile metals were found consistent with their short-term, in-situ mobility assessed in the studied soil, i.e., metal amount released in the soil solution or extracted by cultivated plants. Kinetic EDTA extractions were hypothesized to be more predictive for long-term metal migration with depth.
显示更多 [+] 显示较少 [-]Kinetic and dynamic aspects of soil-plant-snail transfer of cadmium in the field 全文
2008
Gimbert, F. | Mench, M. | Coeurdassier, M. | Badot, P.M. | Vaufleury, A de
Kinetic and dynamic aspects of soil-plant-snail transfer of cadmium in the field 全文
2008
Gimbert, F. | Mench, M. | Coeurdassier, M. | Badot, P.M. | Vaufleury, A de
The proper use of bioaccumulation in the assessment of environmental quality involves accounting for chemical fluxes in organisms. Cadmium (Cd) accumulation kinetics in a soil-plant-snail food chain were therefore investigated in the field under different soil contamination (from 0 to 40 mg kg-1), soil pH (6 and 7) and season. Allowing for an accurate and sensitive assessment of Cd transfer to snails, toxicokinetics appears an interesting tool in the improvement of risk assessment procedures and a way to quantify metal bioavailability for a defined target. On the basis of uptake fluxes, snails proved to be sensitive enough to distinguish moderate soil contaminations. The soil pH did not appear, in the range studied, as a modulating parameter of the Cd transfer from soil to snail whereas the season, by influencing the snail mass, may modify the internal concentrations. The present data specifying a time integrated assessment of environmental factors on metal bioavailability and transfer to terrestrial snails should ensure their rational use in environmental biomonitoring. Toxicokinetics and uptake fluxes can be used to describe the environment contamination by Cd, its bioavailability and transfer to Helix aspersa snails in the field.
显示更多 [+] 显示较少 [-]Kinetic and dynamic aspects of soil–plant–snail transfer of cadmium in the field 全文
2008
Gimbert, Frédéric | Mench, Michel | Coeurdassier, Michaël | Badot, Pierre-Marie | de Vaufleury, Annette | 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) | Université Sciences et Technologies - Bordeaux 1 (UB) | Unité sous contrat biologie environnementale ; Institut National de la Recherche Agronomique (INRA)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)
International audience
显示更多 [+] 显示较少 [-]The dispersal and storage of sediment-associated metals in an arid river system: The Leichhardt River, Mount Isa, Queensland, Australia 全文
2008
Taylor, M.P. | Hudson-Edwards, K.A.
This paper details the distribution of Cu, Pb and Zn in aquatic systems draining Mount Isa Ag-Cu-Pb-Zn Mine in arid northern Queensland, Australia. Sediment-metal concentrations in the <2 mm grain-size fraction adjacent to and downstream of the mine significantly exceed background concentrations (Cu, 159; Pb, 36; Zn, 86 ppm) as well as Australian government sediment quality low trigger guidelines (Cu, 65; Pb, 50; Zn, 200 ppm). Overbank sediments are more contaminated than channel sediments with mean values of Cu, 480; Pb, 540; Zn, 750 ppm. Mean concentrations in cut riverbank samples from the <2 mm fraction were Cu, 195; Pb, 724; Zn, 807 ppm. Corresponding <180 μm samples returned concentrations of Cu, 321; Pb, 995; Zn, 1110 ppm. Delivery of contaminants during wet seasons from Mount Isa Mine and historically contaminated riverbanks remains an ongoing issue. The ease of dust entrainment in arid zones means that sediments enriched in toxic concentrations of metals may be widely dispersed and ultimately ingested and absorbed by biota.
显示更多 [+] 显示较少 [-]Life cycle responses of the midge Chironomus riparius to polycyclic aromatic compound exposure 全文
2008
Paumen, M.L. | Borgman, E. | Kraak, M.H.S. | Gestel, C.A.M van
During acute exposure, polycyclic aromatic compounds (PACs) act mainly by narcosis, but during chronic exposure the same compounds may exert sublethal life cycle effects. The aim of this study was therefore to evaluate the chronic effects of sediment spiked PACs on the emergence of the midge Chironomus riparius. Three isomer pairs were selected, and 28-day LC50 values and 50% emergence times (EMt50) were determined. Concentration-response relationships were observed for phenanthrene, acridine, phenanthridine and acridone. Anthracene and phenanthridone had no effect on total emergence, but did cause a delay in emergence. Calculated porewater LC50 values correlated well with logKow values, suggesting narcosis as mode of action. In contrast, effect concentrations for delay in emergence (EMt50) deviated from narcosis, suggesting a specific mode of action during chronic exposure. It is concluded that emergence is a powerful endpoint to detect life cycle effects of PACs on a key sediment inhabiting invertebrate. Emergence of Chironomus riparius is a sensitive endpoint to detect life cycle effects of PACs.
显示更多 [+] 显示较少 [-]Induced cytochrome P450 1A activity in cichlid fishes from Guandu River and Jacarepaguá Lake, Rio de Janeiro, Brazil 全文
2008
Parente, T.E.M. | De-Oliveira, A.C.A.X. | Paumgartten, F.J.R.
The induction of cytochrome P4501A-mediated activity (e.g. ethoxyresorufin-O-deethylation, EROD) has been used as a biomarker for monitoring fish exposure to AhR-receptor ligands such as polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and polychlorinated dibenzo-dioxins/furans (PCDD/Fs). In this study we found that hepatic EROD is induced in fish (“Nile tilapia”, Oreochromis niloticus and “acará”, Geophagus brasiliensis) from the Guandu River (7-17-fold) and Jacarepaguá Lake (7-fold), Rio de Janeiro, Brazil. Since both cichlid fish are consumed by the local population and the Guandu River is the main source of the drinking water supply for the greater Rio de Janeiro metropolitan area, pollution by cytochrome P4501A-inducing chemicals is a cause for concern and should be further investigated in sediments, water and biota. We additionally showed that EROD activity in the fish liver post-mitochondrial supernatant--simpler, cheaper and less time consuming to prepare than the microsomal fraction--is sufficiently sensitive for monitoring purposes. Increased EROD activity in the liver of cichlid fishes indicated that Guandu River, the source of drinking water supply for Rio de Janeiro is polluted by CYP1A-inducing chemicals.
显示更多 [+] 显示较少 [-]Contribution of ambient ozone to Scots pine defoliation and reduced growth in the Central European forests: A Lithuanian case study 全文
2008
Augustaitis, Algirdas | Bytnerowicz, Andrzej
The study aimed to explore if changes in crown defoliation and stem growth of Scots pines (Pinus sylvestris L.) could be related to changes in ambient ozone (O(3)) concentration in central Europe. To meet this objective the study was performed in 3 Lithuanian national parks, close to the ICP integrated monitoring stations from which data on meteorology and pollution were provided. Contribution of peak O(3) concentrations to the integrated impact of acidifying compounds and meteorological parameters on pine stem growth was found to be more significant than its contribution to the integrated impact of acidifying compounds and meteorological parameters on pine defoliation. Findings of the study provide statistical evidence that peak concentrations of ambient O(3) can have a negative impact on pine tree crown defoliation and stem growth reduction under field conditions in central and northeastern Europe where the AOT40 values for forests are commonly below their phytotoxic levels.
显示更多 [+] 显示较少 [-]Immobilization of mercury by pyrite (FeS2) 全文
2008
Bower, Julia | Savage, Kaye S. | Weinman, Beth | Barnett, Mark O. | Hamilton, William P. | Harper, Willie F.
Elemental mercury (Hg0) is a metal with a number of atypical properties, which has resulted in its use in myriad anthropogenic processes. However, these same properties have also led to severe local subsurface contamination at many places where it has been used. As such, we studied the influence of various parameters on Hg(II) sorption onto pyrite (pH, time, Hg(II) concentration), a potential subsurface reactive barrier. Batch sorption studies revealed that total Hg(II) removal increases with both pH and time. X-ray absorption spectroscopy analysis showed that a transformation in the coordination environment at low pH occurred during aging over 2 weeks, to form an ordered monolayer of monodentate Hg–Cl complexes on pyrite. In column studies packed with pure quartz sand, the transport of Hg(II) was significantly retarded by the presence of a thin pyrite-sand reactive barrier, although dissolved oxygen inhibited Hg(II) sorption onto pyrite in the column. Pyrite may be an effective subsurface reactive barrier for Hg in groundwater.
显示更多 [+] 显示较少 [-]Impact of chronic cadmium exposure at environmental dose on escape behaviour in sea bass (Dicentrarchus labrax L.; Teleostei, Moronidae) 全文
2008
Faucher, Karine | Fichet, Denis | Miramand, Pierre | Lagardere, Jean-paul
The effect of chronic exposure to a low concentration (0.5 mu g l(-1)) of cadmium ions was investigated on escape behaviour of sea bass, Dicentrarchus labrax, using video analysis. Observations were also performed on the microanatomy of lateral system neuromasts. When fish were exposed for 4 h per day over 8 days to the cadmium ions, most of both types of neuromasts observed remained intact. However, some of them presented damaged sensory maculae. Whereas before cadmium exposure, fish responded positively to nearly all the lateral system stimulations, after exposure they decreased by about 10% their positive responses to Stimulations. From the 15th day after the beginning of cadmium exposure, neuromasts presented progressively less damage, cadmium accumulation in gills and scales decreased significantly and fish escape behaviour had recovered. This study presents a new concept in ecotoxicology: using behavioural change to reveal the effects of pollution levels, scarcely detectable by currently used techniques (physiological responses). (C) 2007 Elsevier Ltd. All rights reserved.
显示更多 [+] 显示较少 [-]Predicting sublethal effects of herbicides on terrestrial non-crop species in the field from greenhouse data 全文
2008
Riemens, M.M. | Dueck, T.A. | Kempenaar, C.
Guidelines provided by OECD and EPPO allow the use of data obtained in greenhouse experiments in the risk assessment for pesticides to non-target terrestrial plants in the field. The present study was undertaken to investigate the predictability of effects on field-grown plants using greenhouse data. In addition, the influence of plant development stage on plant sensitivity and herbicide efficacy, the influence of the surrounding vegetation on individual plant sensitivity and of sublethal herbicide doses on the biomass, recovery and reproduction of non-crop plants was studied. Results show that in the future, it might well be possible to translate results from greenhouse experiments to field situations, given sufficient experimental data. The results also suggest consequences at the population level. Even when only marginal effects on the biomass of non-target plants are expected, their seed production and thereby survival at the population level may be negatively affected. The response of greenhouse-grown wild plant species to herbicide exposure could be related to the response of the same species when grown in the field.
显示更多 [+] 显示较少 [-]Spatial and temporal variations of mercury levels in Okefenokee invertebrates: Southeast Georgia 全文
2008
George, B.M. | Batzer, D.
Accumulation of mercury in wetland ecosystems has raised concerns about impacts on wetland food webs. This study measured concentrations of mercury in invertebrates of the Okefenokee Swamp in Georgia, focusing on levels in amphipods, odonates, and crayfish. We collected and analyzed total mercury levels in these invertebrates from 32 sampling stations across commonly occurring sub-habitats. Sampling was conducted in December, May, and August over a two-year period. The highest levels of mercury were detected in amphipods, with total mercury levels often in excess of 20 ppm. Bioaccumulation pathways of mercury in invertebrates of the Okefenokee are probably complex; despite being larger and higher in the food chain, levels in odonates and crayfish were much lower than in amphipods. Mercury levels in invertebrates varied temporally with the highest levels detected in May. There was a lack of spatial variation in mercury levels which is consistent with aerial deposition of mercury. This study measured mercury levels in invertebrates and found the highest levels in amphipods.
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