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Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina horterzsis and Lumbricus terrestris)
2013
Leveque , Thibaut (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Capowiez , Yvan (INRA , Avignon (France). UR 1115 Unité de recherche Plantes et Systèmes de Culture Horticoles) | Schreck , Eva (Géosciences Environnement Toulouse, Toulouse(France). UMR 5563 CNRS/UPS/IRD/CNES) | Mazzia , Christophe (Institut Méditerranéen de Biodiversité et d'Écologie Marine et Continentale(France). UMR CNRS 7263) | Auffan , Mélanie (Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement, Aix-en-Provence(France). Europôle méditerranéen de l’Arbois) | Foucault , Yann (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelleSociété de Traitement Chimique des Métaux, Castanet-Tolosan31326 Castanet-Tolosan Toulouse(France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Austruy , Annabelle (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS) | Dumat , Camille (auteur de correspondance) (Université de ToulouseEcolab Laboratoire d'écologie fonctionnelle, Castanet-Tolosan31326 Castanet-Tolosan (France). INP-ENSATUMR 5245 CNRS-INP-UPS)
Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physicochemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]The impact of oscillating redox conditions: Arsenic immobilisation in contaminated calcareous floodplain soils
2013
Parsons, Christopher T. | Couture, Raoul-Marie | Omoregie, Enoma O. | Bardelli, Fabrizio | Greneche, Jean-Marc | Roman-Ross, Gabriela | Charlet, Laurent
Arsenic contamination of floodplain soils is extensive and additional fresh arsenic inputs to the pedosphere from human activities are ongoing.We investigate the cumulative effects of repetitive soil redox cycles, which occur naturally during flooding and draining, on a calcareous fluvisol, the native microbial community and arsenic mobility following a simulated contamination event.We show through bioreactor experiments, spectroscopic techniques and modelling that repetitive redox cycling can decrease arsenic mobility during reducing conditions by up to 45%. Phylogenetic and functional analyses of the microbial community indicate that iron cycling is a key driver of observed changes to solution chemistry. We discuss probable mechanisms responsible for the arsenic immobilisation observed in-situ. The proposed mechanisms include, decreased heterotrophic iron reduction due to the depletion of labile particulate organic matter (POM), increases to the proportion of co-precipitated vs. aqueous or sorbed arsenic with α-FeOOH/Fe(OH)3 and potential precipitation of amorphous ferric arsenate.
显示更多 [+] 显示较少 [-]Historical arsenic contamination of soil due to long-term phosphate fertiliser applications
2013
Hartley, Tom N. | Macdonald, Andy J. | McGrath, Steve P. | Zhao, Fang-Jie
Archived samples from the Park Grass Experiment, established in 1856, were analysed to determine the impacts of long-term phosphate fertiliser applications on arsenic concentrations in soil and herbage. In plots receiving 35 kg P ha−1 annually (+P), topsoil As concentrations almost doubled from an initial value of ∼10 mg kg−1 during 1888–1947 and remained stable thereafter. The phosphate fertilisers used before 1948 contained 401–1575 mg As kg−1, compared to 1.6–20.3 mg As kg−1 in the later samples. Herbage samples from the +P plots collected during 1888–1947 contained significantly more As than those from the −P plots, but later samples did not differ significantly. Mass-balance calculations show that the increase in soil As can be explained by the As input from P fertiliser applications before 1948. The results demonstrate that the P fertilisers used on the Park Grass Experiment before 1948 caused substantial As contamination of the soil.
显示更多 [+] 显示较少 [-]Micro x-ray absorption spectroscopic analysis of arsenic localization and biotransformation in Chironomus riparius Meigen (Diptera: Chironomidae) and Culex tarsalis Coquillett (Culicidae)
2013
Mogren, Christina L. | Webb, Samuel M. | Walton, William E. | Trumble, John T.
The distribution and speciation of arsenic (As) were analyzed in individuals of various life stages of a midge, Chironomus riparius, and the mosquito Culex tarsalis exposed to 1000 μg/l arsenate. X-ray absorption spectroscopy (XAS) revealed that C. riparius larvae accumulate As in their midgut, with inorganic arsenate [As(V)] being the predominant form, followed by arsenite [As(III)] and an As-thiol. Reduced concentrations of As in pupal and adult stages of C. riparius indicate excretion of As between the larval and pupal stages. In adults, As was limited to the thorax, and the predominant form was an As-thiol. In Cx. tarsalis, As was not found in high enough concentrations to determine As speciation, but the element was distributed throughout the larva. In adults, As was concentrated in the thorax and eyes of adults. These results have implications for understanding the biotransformation of As and its movement from aquatic to terrestrial environments.
显示更多 [+] 显示较少 [-]Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris)
2013
Leveque, Thibaut | Capowiez, Yvan | Schreck, Eva | Mazzia, Christophe | Auffan, Mélanie | Foucault, Yann | Austruy, Annabelle | Dumat, Camille
Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris).The combination of behavioural factors measurements (cast production and biomass) and physico-chemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation.
显示更多 [+] 显示较少 [-]Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species
2013
Norton, Gareth J. | Adomako, Eureka E. | Deacon, Claire M. | Carey, Anne-Marie | Price, Adam H. | Meharg, Andrew A.
Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic.
显示更多 [+] 显示较少 [-]Extractability and bioavailability of Pb and As in historically contaminated orchard soil: Effects of compost amendments
2013
Fleming, Margaret | Tai, Yiping | Zhuang, Ping | McBride, Murray B.
The availability of Pb and As in an historically contaminated orchard soil, after amendment with compost and aging in the field, was determined by single-step chemical extraction with 1.0 M ammonium acetate at pH 4.8, sequential extraction using the modified BCR test, and a redworm bioassay in the laboratory. The efficiency of soil Pb extraction by ammonium acetate was greater at higher total soil Pb but was reduced by compost amendment. Conversely, the extraction efficiency of total soil As increased with compost amendment, but was not sensitive to total soil As. The redworm bioassay indicated Pb (but not As) bioavailability to be reduced by soil amendment with compost, a result consistent with the ammonium acetate extraction test but not reflected in modified BCR test. Electron microprobe studies of the orchard soil revealed Pb and As to be spatially associated in discrete particles along with phosphorus and iron.
显示更多 [+] 显示较少 [-]Assessment of exposure to heavy metals and health risks among residents near abandoned metal mines in Goseong, Korea
2013
Ji, Kyunghee | Kim, Jungkon | Lee, Minjung | Park, Soyoung | Kwon, Ho-Jang | Cheong, Hae-Kwan | Jang, Jae-Yeon | Kim, Dae-Seon | Yu, Seungdo | Kim, Young Wook | Lee, Kwang-Young | Yang, Seoung-Oh | Jhung, Ik Jae | Yang, Won-Ho | Paek, Do-Hyun | Hong, Yun-Chul | Choi, Kyungho
Metal contamination from mining activity is of great concern because of potential health risks to the local inhabitants. In the present study, we investigated the levels of Cd, Cu, As, Pb, and Zn in environmental samples and foodstuffs grown in the vicinity of the mines in Goseong, Korea, and evaluated potential health risks among local residents. Soils near the mines exceeded the soil quality standard values of Cu, As, and Zn contamination. The concentrations of Cd, Cu, Pb, and Zn in crop samples collected from the study area were significantly higher than those of the reference area. Some rice samples collected from the study area exceeded the maximum permissible level of 0.2 mg Cd/kg. The intake of rice was identified as a major contributor (≥75%) to the estimated daily intake among the residents. The average estimated daily intakes of metals were, however, below the provisional tolerable daily intake.
显示更多 [+] 显示较少 [-]Environmental lead exposure risks associated with children's outdoor playgrounds
2013
Taylor, Mark Patrick | Camenzuli, Danielle | Kristensen, Louise Jane | Forbes, Miriam | Zahran, Sammy
This study examines exposure risks associated with lead smelter emissions at children's public playgrounds in Port Pirie, South Australia. Lead and other metal values were measured in air, soil, surface dust and on pre- and post-play hand wipes. Playgrounds closest to the smelter were significantly more lead contaminated compared to those further away (t(27.545) = 3.76; p = .001). Port Pirie post-play hand wipes contained significantly higher lead loadings (maximum hand lead value of 49,432 μg/m2) than pre-play hand wipes (t(27) = 3.57, p = .001). A 1% increase in air lead (μg/m3) was related to a 0.713% increase in lead dust on play surfaces (95% CI, 0.253–1.174), and a 0.612% increase in post-play wipe lead (95% CI, 0.257–0.970). Contaminated dust from smelter emissions is determined as the source and cause of childhood lead poisoning at a rate of approximately one child every third day.
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