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Combining passive samplers and biomonitors to evaluate endocrine disrupting compounds in a wastewater treatment plant by LC/MS/MS and bioassay analyses Полный текст
2009
Liscio, C. | Magi, E. | Di Carro, M. | Suter, M.J.F. | Vermeirssen, E.L.M.
Two types of integrative sampling approaches (passive samplers and biomonitors) were tested for their sampling characteristics of selected endocrine disrupting compounds (EDCs). Chemical analyses (LC/MS/ MS) were used to determine the amounts of five EDCs (nonylphenol, bisphenol A, estrone, 17b-estradiol and 17a-ethinylestradiol) in polar organic chemical integrative samplers (POCIS) and freshwater mussels (Unio pictorum); both had been deployed in the influent and effluent of a municipal wastewater treatment plant (WWTP) in Genoa, Italy. Estrogenicity of the POCIS samples was assessed using the yeast estrogen screen (YES). Estradiol equivalent values derived from the bioassay showed a positive correlation with estradiol equivalents calculated from chemical analyses data. As expected, the amount of estrogens and EEQ values in the effluent were lower than those in the influent. Passive sampling proved to be the preferred method for assessing the presence of these compounds since employing mussels had several disadvantages both in sampling efficiency and sample analyses.
Показать больше [+] Меньше [-]Metal and metalloid accumulation in shrews (Soricomorpha, Mammalia) from two protected Mediterranean coastal sites Полный текст
2009
Sánchez-Chardi, Alejandro | López-Fuster, María José
Although ecotoxicological data on heavy metals are abundant, information on other potentially toxic elements with attributed deficiency and/or toxic disturbances is scarce. Here we quantify zinc, copper, iron, manganese, chromium, molybdenum, strontium, barium, and boron in bones of greater white-toothed shrews, Crocidura russula, inhabiting two protected Mediterranean coastal sites: the Ebro Delta, a wetland impacted by human activities, and the Medas Islands, a reference site. Natural and anthropogenic inputs significantly increase Fe, Mn, Mo, Sr, Ba, and B in specimens from the Ebro Delta, whereas Cu and Cr were higher in Medas' shrews. Principal component analysis allowed complete separation between sites along the first two axes in particular due to B, Sr, and Cu. This study provides metal reference values in bones of insectivores, explores their variability and bioaccumulation patterns in depth, and assesses the potential environmental risk and toxicity for biota exposed to the above elements. Sr, Ba, Fe, Mn, Mo and B were bioaccumulated in bones of shrews from the Ebro Delta area and Cu in Medas Islands, whereas Cr and Zn showed similar levels at both sites.
Показать больше [+] Меньше [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Полный текст
2009
Roche, H. | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, D. | Ramade, F.
Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Полный текст
2009
Roche, H. | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, D. | Ramade, F.
During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp'-DDE, dieldrin, aldrin, heptachlor, endosulfan ...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Показать больше [+] Меньше [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Полный текст
2009
Roche, Hélène | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, Damien | Ramade, F. | Ecologie Systématique et Evolution (ESE) ; Université Paris-Sud - Paris 11 (UP11)-AgroParisTech-Centre National de la Recherche Scientifique (CNRS) | Universidade Federal do Paraná [Curitiba, Brasil] = Federal University of Paraná [Curitiba, Brazil] = Université fédérale du Paraná [Curitiba, Brésil] (UFPR) | Réserve Nationale de Camargue ; Réserve Naturelle Nationale de Camargue ; Réserves Naturelles de France-Réserves Naturelles de France | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL)
International audience | During a decade (1996–2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan…) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Показать больше [+] Меньше [-]Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France) Полный текст
2009
Roche, Hélène | Vollaire, Y. | Persic, A. | Buet, A. | Oliveira-Ribeiro, C. | Coulet, E. | Banas, Damien | Ramade, F.
During a decade (1996–2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp′-DDE, dieldrin, aldrin, heptachlor, endosulfan…) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas. The Vaccarès Lagoon trophic web biomagnifies organochlorine pollutants.
Показать больше [+] Меньше [-]Predicting bioremediation of hydrocarbons: Laboratory to field scale Полный текст
2009
Diplock, E.E. | Mardlin, D.P. | Killham, K.S. | Paton, G.I.
There are strong drivers to increasingly adopt bioremediation as an effective technique for risk reduction of hydrocarbon impacted soils. Researchers often rely solely on chemical data to assess bioremediation efficiently, without making use of the numerous biological techniques for assessing microbial performance. Where used, laboratory experiments must be effectively extrapolated to the field scale. The aim of this research was to test laboratory derived data and move to the field scale. In this research, the remediation of over thirty hydrocarbon sites was studied in the laboratory using a range of analytical techniques. At elevated concentrations, the rate of degradation was best described by respiration and the total hydrocarbon concentration in soil. The number of bacterial degraders and heterotrophs as well as quantification of the bioavailable fraction allowed an estimation of how bioremediation would progress. The response of microbial biosensors proved a useful predictor of bioremediation in the absence of other microbial data. Field-scale trials on average took three times as long to reach the same endpoint as the laboratory trial. It is essential that practitioners justify the nature and frequency of sampling when managing remediation projects and estimations can be made using laboratory derived data. The value of bioremediation will be realised when those that practice the technology can offer transparent lines of evidence to explain their decisions. Detailed biological, chemical and physical characterisation reduces uncertainty in predicting bioremediation.
Показать больше [+] Меньше [-]The importance of ammonium mobility in nitrogen-impacted unfertilized grasslands: A critical reassessment Полный текст
2009
Mian, Ishaq Ahmad | Riaz, Muhammad | Cresser, Malcolm S.
The physico-chemical absorption characteristics of ammonium-N for 10 soils from 5 profiles in York, UK, show its high potential mobility in N deposition-impacted, unfertilized, permanent grassland soils. Substantial proportions of ammonium-N inputs were retained in the solution phase, indicating that ammonium translocation plays an important role in the N cycling in, and losses from, such soils. This conclusion was further supported by measuring the ammonium-N leaching from intact plant/soil microcosms. The ammonium-N absorption characteristics apparently varied with soil pH, depth and soil texture. It was concluded for the most acid soils especially that ammonium-N leached from litter horizons could be seriously limiting the capacity of underlying soils to retain ammonium. Contrary to common opinion, more attention therefore needs to be paid to ammonium leaching and its potential role in biogeochemical N cycling in semi-natural soil systems subject to atmospheric pollution. mmonium mobility is more important than previously thought in N-impacted, unfertilized grasslands.
Показать больше [+] Меньше [-]Assessment of atmospheric sulfur with the epilithic moss Haplocladium microphyllum: Evidences from tissue sulfur and δ34S analysis Полный текст
2009
Liu, Xue-Yan | Xiao, Hua-Yuan | Liu, Cong-Qiang | Xiao, Hong-Wei | Wang, Yan-Li
The application of geochemical signals in mosses is more and more popular to investigate the deposition of atmospheric pollutants, but it is unclear whether records of atmospheric sulfur in mosses differ between their diverse habitats. This study aimed to investigate the influence of growing condition on tissue sulfur and δ³⁴S of Haplocladium microphyllum. Epilithic and terricolous mosses in open fields, mosses under different canopy conditions were considered. We found that tissue sulfur and δ³⁴S of mosses under different habitats were not consistent and could not be compared for atmospheric sulfur research with each other even collected at the same site, moss sulfur and δ³⁴S records would be distorted by subsoil and upper canopies in different degrees, which possibly mislead the interpretation of atmospheric sulfur level and sources. Consequently, mosses on open rocks can be used reliably to assess atmospheric-derived sulfur in view of their identical sulfur and δ³⁴S evidences. Mosses on open rocky surfaces are reliable bioindicators of atmospheric sulfur deposition.
Показать больше [+] Меньше [-]Ozone and urban forests in Italy Полный текст
2009
Paoletti, Elena
Ozone levels along urban-to-rural gradients in three Italian cities (Milan, Florence, Bari) showed that average AOT40 values at rural and suburban sites were 2.6 times higher than those determined at urban sites. However, O3 also exceeded the European criteria to protect forest health at urban sites, even when the standards for human health protection were met. For protecting street trees in Mediterranean cities, the objectives of measurement at urban sites should extend from the protection of human health to the protection of vegetation as well. A review of forest effects on O3 pollution and of O3 pollution on forest conditions in Italian cities showed that it was not possible to distinguish the effect of O3 in the complex mixture of urban pollutants and stressors. A preliminary list of tree species for urban planning in the Mediterranean area shows the average tree capacity of O3 removal and VOC emission. European criteria to protect human health from ozone may not protect urban forests in the Mediterranean area.
Показать больше [+] Меньше [-]Integrative approach to delineate natural attenuation of chlorinated benzenes in anoxic aquifers Полный текст
2009
Stelzer, Nicole | Imfeld, Gwenaël | Thullner, Martin | Lehmann, Jürgen | Poser, Alexander | Richnow, Hans H. | Nijenhuis, Ivonne
Biodegradation of chlorobenzenes was assessed at an anoxic aquifer by combining hydrogeochemistry and stable isotope analyses. In situ microcosm analysis evidenced microbial assimilation of chlorobenzene (MCB) derived carbon and laboratory investigations asserted mineralization of MCB at low rates. Sequential dehalogenation of chlorinated benzenes may affect the isotope signature of single chlorobenzene species due to simultaneous depletion and enrichment of 13C, which complicates the evaluation of degradation. Therefore, the compound-specific isotope analysis was interpreted based on an isotope balance. The enrichment of the cumulative isotope composition of all chlorobenzenes indicated in situ biodegradation. Additionally, the relationship between hydrogeochemistry and degradation activity was investigated by principal component analysis underlining variable hydrogeochemical conditions associated with degradation activity at the plume scale. Although the complexity of the field site did not allow straightforward assessment of natural attenuation processes, the application of an integrative approach appeared relevant to characterize the in situ biodegradation potential. Lines of evidence for in situ biodegradation of chlorinated benzenes in an anoxic aquifer by combining hydrogeochemical and stable isotope data with multivariate statistics.
Показать больше [+] Меньше [-]Antibiotic removal from water: Elimination of amoxicillin and ampicillin by microscale and nanoscale iron particles Полный текст
2009
Ghauch, Antoine | Tuqan, Almuthanna | Assi, Hala Abou
Zerovalent iron powder (ZVI or Fe⁰) and nanoparticulate ZVI (nZVI or nFe⁰) are proposed as cost-effective materials for the removal of aqueous antibiotics. Results showed complete removal of Amoxicillin (AMX) and Ampicillin (AMP) upon contact with Fe⁰ and nFe⁰. Antibiotics removal was attributed to three different mechanisms: (i) a rapid rupture of the β-lactam ring (reduction), (ii) an adsorption of AMX and AMP onto iron corrosion products and (iii) sequestration of AMX and AMP in the matrix of precipitating iron hydroxides (co-precipitation with iron corrosion products). Kinetic studies demonstrated that AMP and AMX (20 mg L⁻¹) undergo first-order decay with half-lives of about 60.3 ± 3.1 and 43.5 ± 2.1 min respectively after contact with ZVI under oxic conditions. In contrast, reactions under anoxic conditions demonstrated better degradation with t1/2 of about 11.5 ± 0.6 and 11.2 ± 0.6 min for AMP and AMX respectively. NaCl additions accelerated Fe⁰ consumption, shortening the service life of Fe⁰ treatment systems. 21Fe⁰ is efficient for the aqueous removal of the β-lactam antibiotics and chlorides enhanced the removal rate by sustaining the process of iron corrosion.
Показать больше [+] Меньше [-]In vitro residual anti-bacterial activity of difloxacin, sarafloxacin and their photoproducts after photolysis in water Полный текст
2009
Kusari, Souvik | Prabhakaran, Deivasigamani | Lamshoft, Marc | Spiteller, M (Michael)
Fluoroquinolones like difloxacin (DIF) and sarafloxacin (SARA) are adsorbed in soil and enter the aquatic environment wherein they are subjected to photolytic degradation. To evaluate the fate of DIF and SARA, their photolysis was performed in water under stimulated natural sunlight conditions. DIF primarily degrades to SARA. On prolonged photodegradation, seven photoproducts were elucidated by HR-LC-MS/MS, three of which were entirely novel. The residual anti-bacterial activities of DIF, SARA and their photoproducts were studied against a group of pathogenic strains. DIF and SARA revealed potency against both Gram-positive and -negative bacteria. The photoproducts also exhibited varying degrees of efficacies against the tested bacteria. Even without isolating the individual photoproducts, their impact on the aquatic environment could be assessed. Therefore, the present results call for prudence in estimating the fate of these compounds in water and in avoiding emergence of resistance in bacteria caused by the photoproducts of DIF and SARA.
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