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Sorption of apolar and polar organic contaminants by waste tire rubber and its chars in single- and bi-solute systems Full text
2011
Lian, Fei | Huang, Fang | Chen, Wei | Xing, Baoshan | Zhu, Lingyan
Single- and bi-solute sorption of organic compounds [1,3-dichlorbenzene (DCB), 1,3-dinitrobenzene (DNB) and 2,4-dichlorophenol (DCP)] on ground tire rubber and its chars was studied. The chars were prepared by pyrolyzing tire rubber at different temperatures (200–800 °C). Their surface area, aromaticity and hydrophobicity increase greatly with pyrolytic temperature, and the polymeric phase is partly converted into a condensed phase. The sorption of DNB and DCP increases with pyrolytic temperature and is characterized by a transition from a partition dominant to an adsorption dominant process. However, the sorption of DCB linearly decreases with the pyrolytic temperature. The enhanced adsorption of DNB and DCP on carbonized phase is primarily attributed to nonhydrophobic interactions such as π–π electron-donor–acceptor interactions and/or H bonding. The higher partition of DCB to polymeric phase is attributed to its high hydrophobicity. Competitive sorption between DCB and DCP on the tire chars is highly dependent on dissociation of the latter.
Show more [+] Less [-]Reduced ozone by air filtration consistently improved grain yield in wheat Full text
2011
This study considered effects of reduced [O₃] on wheat yield. Open-top chamber charcoal filtered air treatments were compared with non-filtered treatments for field-grown wheat. 30 experiments meeting requirements were found, representing nine countries in North America, Europe and Asia. 26 experiments reported improved yield and 4 experiments reduced yield by filtration, a significant positive effect. Average yield improvement was 9%. Average daytime [O₃] was reduced by filtration from 35 to 13 nmol mol⁻¹. Filtration efficiency was 63% for O₃ and 56% for SO₂. For NOₓ it was observed that NO₂ was reduced and NO increased by filtration. Thus, filters convert NO₂ to NO. Most experiments reported low or very low [SO₂] and [NOₓ]. Thus, O₃ can be concluded to be the main phytotoxic component in the experiments. Elevated [NO₂] was observed in one experiment. The conclusion is that current [O₃] over large parts of the world adversely affect wheat yield.
Show more [+] Less [-]Heavy metal concentration survey in soils and plants of the Les Malines Mining District (Southern France): implications for soil restoration Full text
2011
Escarré, José | Lefèbvre, Claude | Raboyeau, Stephan | dos Santos, Anabelle | Gruber, Wolf | Cleyet-Marel, Jean-Claude | Frérot, Hélène | Noret, Nausicaa | Mahieu, Stéphanie | Collin, Christian | van Oort, Folkert | Centre d’Ecologie Fonctionnelle et Evolutive (CEFE) ; Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Laboratoire d'Ecologie végétale et de Biogéochimie ; Université libre de Bruxelles (ULB) | Laboratoire des symbioses tropicales et méditerranéennes (UMR LSTM) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Montpellier 1 (UM1)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Génétique et évolution des populations végétales (GEPV) ; Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS) | Physicochimie et Ecotoxicologie des SolS d'Agrosystèmes Contaminés (PESSAC) ; Institut National de la Recherche Agronomique (INRA) | Agence de l'Environnement et de la Maitrise de l'Energie (04.72.C.0037)
Heavy metal concentration survey in soils and plants of the Les Malines Mining District (Southern France): implications for soil restoration Full text
2011
Escarré, José | Lefèbvre, Claude | Raboyeau, Stephan | dos Santos, Anabelle | Gruber, Wolf | Cleyet-Marel, Jean-Claude | Frérot, Hélène | Noret, Nausicaa | Mahieu, Stéphanie | Collin, Christian | van Oort, Folkert | Centre d’Ecologie Fonctionnelle et Evolutive (CEFE) ; Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Laboratoire d'Ecologie végétale et de Biogéochimie ; Université libre de Bruxelles (ULB) | Laboratoire des symbioses tropicales et méditerranéennes (UMR LSTM) ; Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Montpellier 1 (UM1)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro) | Génétique et évolution des populations végétales (GEPV) ; Université de Lille, Sciences et Technologies-Centre National de la Recherche Scientifique (CNRS) | Physicochimie et Ecotoxicologie des SolS d'Agrosystèmes Contaminés (PESSAC) ; Institut National de la Recherche Agronomique (INRA) | Agence de l'Environnement et de la Maitrise de l'Energie (04.72.C.0037)
International audience | Mining activities generate spoils and effluents with extremely high metal concentrations of heavy metals that might have adverse effects on ecosystems and human health. Therefore, information on soil and plant metal concentrations is needed to assess the severity of the pollution and develop a strategy for soil reclamation such as phytoremediation. Here, we studied soils and vegetation in three heavily contaminated sites with potential toxic metals and metalloids (Zn, Pb, Cd, As, TI) in the mining district of Les Malines in the Languedoc region (southern France). Extremely high concentrations were found at different places such as the Les Aviniéres tailing basins (up to 160,000 mg kg-1 Zn, 90,000 mg kg-1 Pb, 9,700 mg kg-1 of As and 245 mg kg-1 of Tl) near a former furnace. Metal contamination extended several kilometres away from the mine sites probably because of the transport of toxic mining residues by wind and water. Spontaneous vegetation growing on the three mine sites was highly diversified and included 116 plant species. The vegetation cover consisted of species also found in non-contaminated soils, some of which have been shown to be metaltolerant ecotypes (Festuca arvernensis, Koeleria vallesiana and Armeria arenaria) and several Zn, Cd and Tl hyperaccumulators such as Anthyllis vulneraria, Thlaspi caerulescens, Iberis intermedia and Silene latifolia. This latter species was highlighted as a new thallium hyperaccumulator, accumulating nearly 1,500 mg kg-1. These species represent a patrimonial interest for their potential use for the phytoremediation of toxic metal-polluted areas.
Show more [+] Less [-]Heavy Metal Concentration Survey in Soils and Plants of the Les Malines Mining District (Southern France): Implications for Soil Restoration Full text
2011
Escarré, Jose | Lefebvre, Claude | Raboyeau, Stephan | Dossantos, Anabelle | Gruber, Wolf | Cleyet Marel, Jean Claude | Frérot, Helene | Noret, Nausicaa | Mahieu, Stéphanie | Collin, Christian | van Oort, Folkert
Mining activities generate spoils and effluents with extremely high metal concentrations of heavy metals that might have adverse effects on ecosystems and human health. Therefore, information on soil and plant metal concentrations is needed to assess the severity of the pollution and develop a strategy for soil reclamation such as phytoremediation. Here, we studied soils and vegetation in three heavily contaminated sites with potential toxic metals and metalloids (Zn, Pb, Cd, As, TI) in the mining district of Les Malines in the Languedoc region (southern France). Extremely high concentrations were found at different places such as the Les Aviniéres tailing basins (up to 160,000 mg kg–1 Zn, 90,000 mg kg–1 Pb, 9,700 mg kg–1 of As and 245 mg kg–1 of Tl) near a former furnace. Metal contamination extended several kilometres away from the mine sites probably because of the transport of toxic mining residues by wind and water. Spontaneous vegetation growing on the three mine sites was highly diversified and included 116 plant species. The vegetation cover consisted of species also found in non-contaminated soils, some of which have been shown to be metal-tolerant ecotypes (Festuca arvernensis, Koeleria vallesiana and Armeria arenaria) and several Zn, Cd and Tl hyperaccumulators such as Anthyllis vulneraria, Thlaspi caerulescens, Iberis intermedia and Silene latifolia. This latter species was highlighted as a new thallium hyperaccumulator, accumulating nearly 1,500 mg kg–1. These species represent a patrimonial interest for their potential use for the phytoremediation of toxic metal-polluted areas.
Show more [+] Less [-]Remediation of polycyclic aromatic hydrocarbon (PAH) contaminated soil through composting with fresh organic wastes Full text
2011
Zhang, Yuan | Zhu, Yong-Guan | Houot, Sabine | Qiao, Min | Nunan, Naoise | Garnier, Patricia | State Key Laboratory for Mineral Deposits Research ; Nanjing University (NJU) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)
Remediation of polycyclic aromatic hydrocarbon (PAH) contaminated soil through composting with fresh organic wastes Full text
2011
Zhang, Yuan | Zhu, Yong-Guan | Houot, Sabine | Qiao, Min | Nunan, Naoise | Garnier, Patricia | State Key Laboratory for Mineral Deposits Research ; Nanjing University (NJU) | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Biogéochimie et écologie des milieux continentaux (Bioemco) ; École normale supérieure - Paris (ENS-PSL) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS)
International audience | Composting may enhance bioremediation of PAH-contaminated soils by providing organic substrates that stimulate the growth of potential microbial degraders. However, the influence of added organic matter (OM) together with the microbial activities on the dissipation of PAHs has not yet been fully assessed. Materials and methods An in-vessel composting-bioremediation experiment of a contaminated soil amended with fresh wastes was carried out. Four different experimental conditions were tested in triplicate during 60 days using laboratory-scale reactors: treatment S (100%soil),W(100%wastes), SW(soil/ wastemixture), and SWB(soil/wastemixture with inoculation of degrading microorganisms). Results and discussion A dry mass loss of 35±5% was observed in treatments with organic wastes during composting in all the treatments except treatment S. The dissipation of the 16 USEPA-listed PAHs was largely enhanced from no significant change to 50.5±14.8% (for SW)/63.7±10.0% (for SWB).More obvious dissipation was observed when fresh wastes were added at the beginning of composting to the contaminated soil, without significant difference between the inoculated and non-inoculated treatments. Phospholipid fatty acid (PLFA) profiling showed that fungi and G-bacteria dominated at the beginning of experiment and were probably involved in PAH dissipation. Subsequently, greater relative abundances of G+bacteria were observed as PAH dissipation slowed down. Conclusions The results suggest that improving the composting process with optimal organic compositions may be a feasible remediation strategy in PAH-contaminated soils through stimulation of active microbial populations.
Show more [+] Less [-]Remediation of polycyclic aromatic hydrocarbon (PAH) contaminated soil through composting with fresh organic wastes Full text
2011
Zhang, Yuan | Zhu, Yong-Guan | Houot, Sabine | Qiao, Min | Nunan, Naoise | Garnier, Patricia
INTRODUCTION: Composting may enhance bioremediation of PAH-contaminated soils by providing organic substrates that stimulate the growth of potential microbial degraders. However, the influence of added organic matter (OM) together with the microbial activities on the dissipation of PAHs has not yet been fully assessed. MATERIALS AND METHODS: An in-vessel composting-bioremediation experiment of a contaminated soil amended with fresh wastes was carried out. Four different experimental conditions were tested in triplicate during 60 days using laboratory-scale reactors: treatment S (100% soil), W (100% wastes), SW (soil/waste mixture), and SWB (soil/waste mixture with inoculation of degrading microorganisms). RESULTS AND DISCUSSION: A dry mass loss of 35 ± 5% was observed in treatments with organic wastes during composting in all the treatments except treatment S. The dissipation of the 16 USEPA-listed PAHs was largely enhanced from no significant change to 50.5 ± 14.8% (for SW)/63.7 ± 10.0% (for SWB). More obvious dissipation was observed when fresh wastes were added at the beginning of composting to the contaminated soil, without significant difference between the inoculated and non-inoculated treatments. Phospholipid fatty acid (PLFA) profiling showed that fungi and G-bacteria dominated at the beginning of experiment and were probably involved in PAH dissipation. Subsequently, greater relative abundances of G + bacteria were observed as PAH dissipation slowed down. CONCLUSIONS: The results suggest that improving the composting process with optimal organic compositions may be a feasible remediation strategy in PAH-contaminated soils through stimulation of active microbial populations.
Show more [+] Less [-]The removal of microorganisms and organic micropollutants from wastewater during infiltration to aquifers after irrigation of farmland in the Tula Valley, Mexico Full text
2011
Chávez, Alma | Maya, Catalina | Gibson, Richard | Jiménez, Blanca
The Tula Valley receives untreated wastewater from Mexico City for agricultural irrigation, half of which infiltrates to aquifers from where drinking water is extracted. Samples of wastewater and infiltrated water from three areas of the valley were analyzed for microorganisms, organic micropollutants, and some basic parameters. Concentrations of microorganisms in the infiltrated water were generally very low but the incidence of fecal coliforms (present in 68% of samples), somatic bacteriophages (36%), Giardia spp. (14%), and helminth eggs (8%) suggested a health risk. Organic micropollutants, often present at high concentrations in the wastewater, were generally absent from the infiltrated water except carbamazepine which was in 55% of samples (up to 193 ng/L). There was no correlation between carbamazepine concentrations and the presence of microorganisms but highest concentrations of carbamazepine and boron coincided. A treatment such as nanofiltration would be necessary for the infiltrated water to be a safe potable supply.
Show more [+] Less [-]Spatial and seasonal variations of polycyclic aromatic hydrocarbons in Haihe Plain, China Full text
2011
Wang, Rong | Cao, Hongying | Li, Wei | Wang, Wei | Wang, Wentao | Zhang, Liwen | Liu, Jiumeng | Ouyang, Huiling | Tao, Shu
A dynamic fugacity model was developed to simulate the spatial and seasonal variations of PAHs in Haihe Plain, China. The calculated and measured concentrations exhibited good consistency in magnitude with deviations within a factor of 4 in air and 2 in soil. The spatial distributions of PAHs in air were mainly controlled by emission while the seasonal variations were dominated by emission and gas–particle partition. In soil, the spatial distributions of PAHs were controlled by the soil organic carbon content while the seasonal variations were insignificant. The severest soil contamination was observed in Shanxi and followed by the southwest of Hebei province. Transfer fluxes of total PAHs between air and soil were calculated. The spatial distribution of air-to-soil flux was closely related to the landcover while the soil-to-air flux changed with soil organic matter content. Monte Carlo simulation was done to evaluate the uncertainty of the estimated results in air.
Show more [+] Less [-]Application of air pollution dispersion modeling for source-contribution assessment and model performance evaluation at integrated industrial estate-Pantnagar Full text
2011
Banerjee, T. | Barman, S.C. | Srivastava, R.K.
Source-contribution assessment of ambient NO₂ concentration was performed at Pantnagar, India through simulation of two urban mathematical dispersive models namely Gaussian Finite Line Source Model (GFLSM) and Industrial Source Complex Model (ISCST-3) and model performances were evaluated. Principal approaches were development of comprehensive emission inventory, monitoring of traffic density and regional air quality and conclusively simulation of urban dispersive models. Initially, 18 industries were found responsible for emission of 39.11 kg/h of NO₂ through 43 elevated stacks. Further, vehicular emission potential in terms of NO₂ was computed as 7.1 kg/h. Air quality monitoring delineates an annual average NO₂ concentration of 32.6 μg/m³. Finally, GFLSM and ISCST-3 were simulated in conjunction with developed emission inventories and existing meteorological conditions. Models simulation indicated that contribution of NO₂ from industrial and vehicular source was in a range of 45–70% and 9–39%, respectively. Further, statistical analysis revealed satisfactory model performance with an aggregate accuracy of 61.9%.
Show more [+] Less [-]Zinc accumulation and synthesis of ZnO nanoparticles using Physalis alkekengi L Full text
2011
Qu, Jiao | Yuan, Xing | Wang, Xinhong | Shao, Peng
A field survey and greenhouse experiments were conducted using Physalis alkekengi L. to investigate strategies of phytoremediation. In addition, ZnO nanoparticles were synthesized using P. alkekengi. P. alkekengi plants grew healthily at Zn levels from 50 to 5000mgkg⁻¹ in soils. The plants incorporated Zn into their aerial parts (with mean dry weight values of 235–10,980mgkg⁻¹) and accumulated biomass (with a mean dry weight of 25.7gplant⁻¹) during 12 weeks. The synthesized ZnO nanoparticles showed a polydisperse behavior and had a mean size of 72.5nm. The results indicate that P. alkekengi could be used for the remediation of zinc-contaminated soils. Moreover, the synthetic method of synthesizing ZnO nanoparticles from Zn hyperaccumulator plants constitutes a new insight into the recycling of metals in plant sources.
Show more [+] Less [-]Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China Full text
2011
Pan, Xiaohui | Tang, Jianhui | Chen, Yingjun | Li, Jun | Zhang, Gan
PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g⁻ ¹ dry weight (dw) with a mean value of 1.1 ng g⁻ ¹ dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.
Show more [+] Less [-]New insights into the sorption mechanism of cadmium on red mud Full text
2011
Luo, Lei | Ma, Chenyan | Ma, Yibing | Zhang, Shuzhen | Lv, Jitao | Cui, Mingqi
Effectiveness and mechanism of cadmium (Cd) sorption on original, acidified and ball milling nano-particle red muds were investigated using batch sorption experiments, sequential extraction analysis and X-ray absorption near edge structure (XANES) spectroscopy. The maximum sorption capacity of Cd was 0.16, 0.19, and 0.21mol/kg for the original, acidified, and nano-particle red muds at pH 6.5, respectively. Both acidification and ball-milling treatments significantly enhanced Cd sorption and facilitated transformation of Cd into less extractable fractions. The Cd LIII-edge XANES analysis indicated the formation of inner-sphere complexes of Cd similar to XCdOH (X represents surface groups on red mud) on the red mud surfaces although outer-sphere complexes of Cd were the primary species. This work shed light on the potential application of red mud to remediate Cd-contaminated soils and illustrated the promising tool of XANES spectroscopy for speciation of multicomponent systems of environmental relevance.
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