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A review of metal (Pb and Zn) sensitive and pH tolerant bioassay organisms for risk screening of metal-contaminated acidic soils Full text
2013
Chapman, E.Emily V. | Dave, Göran | Murimboh, John D.
To improve risk estimates at the screening stage of Ecological Risk Assessment (ERA), short duration bioassays tailored to undisturbed soil cores from the contaminated site could be useful. However, existing standardized bioassays use disturbed soil samples and often pH sensitive organisms. This is a problem as naturally acidic soils are widespread. Changing soil properties to suit the test organism may change metal bioavailability, leading to erroneous risk estimates. For bioassays in undisturbed soil cores to be effective, species able to withstand natural soil properties must be identified. This review presents a critical examination of bioassay species' tolerance of acidic soils and sensitivity to metal contaminants such as Pb and Zn. Promising organisms include; Dendrobaena octaedra, Folsomia candida, Caenorhabditis elegans, Oppia nitens, Brassica rapa, Trifolium pratense, Allium cepa, Quercus rubra and Acer rubrum. The MetSTICK test and the Bait lamina test were also identified as suitable microorganism tests.
Show more [+] Less [-]Cumulative impacts of human activities on urban garden soils: Origin and accumulation of metals Full text
2013
Szolnoki, Zs | Farsang, A. | Puskás, I.
The concentration of heavy metals and soil properties in fifty urban garden soils of Szeged (SE Hungary) were determined to evaluate the cumulative impacts of urbanization and cultivation on these soils. Using two enrichment factors (EFs) (based on reference horizon; Ti as reference element) and multivariate statistical analysis (PCA), the origin of the studied elements was defined.According to statistical coincidence of EFs confirmed by t-test, anthropogenic enrichment of Cu (EF = 4), Zn (EF = 2.7) and Pb (EF = 2.5) was significant in topsoils. Moreover, PCA also revealed the geogenic origin of Ni, Co, Cr and As and differentiated two groups of the anthropogenic metals [Pb, Zn] [Cu]. Spatial distribution of the metals visualized by GIS reflected the traffic origin of Pb; while based on ANOVA, the anthropogenic source of Cu is relevant (mainly pesticides) and there is a statistically significant difference in its concentration depending on land use.
Show more [+] Less [-]Nitrogen deposition alters nitrogen cycling and reduces soil carbon content in low-productivity semiarid Mediterranean ecosystems Full text
2013
Ochoa-Hueso, Raúl | Maestre, Fernando T. | de los Ríos, Asunción | Valea, Sergio | Theobald, Mark R. | Vivanco, Marta G. | Manrique, Esteban | Bowker, Mathew A.
Anthropogenic N deposition poses a threat to European Mediterranean ecosystems. We combined data from an extant N deposition gradient (4.3–7.3 kg N ha−1 yr−1) from semiarid areas of Spain and a field experiment in central Spain to evaluate N deposition effects on soil fertility, function and cyanobacteria community. Soil organic N did not increase along the extant gradient. Nitrogen fixation decreased along existing and experimental N deposition gradients, a result possibly related to compositional shifts in soil cyanobacteria community. Net ammonification and nitrification (which dominated N-mineralization) were reduced and increased, respectively, by N fertilization, suggesting alterations in the N cycle. Soil organic C content, C:N ratios and the activity of β-glucosidase decreased along the extant gradient in most locations. Our results suggest that semiarid soils in low-productivity sites are unable to store additional N inputs, and that are also unable to mitigate increasing C emissions when experiencing increased N deposition.
Show more [+] Less [-]Investigation of gold nanoparticles uptake and their tissue level distribution in rice plants by laser ablation-inductively coupled-mass spectrometry Full text
2013
Koelmel, Jeremy | Leland, Thomas | Wang, Huanhua | Amarasiriwardena, Dulasiri | Xing, Baoshan
The tissue level uptake and spatial distribution of gold nanoparticles (AuNPs) in rice (Oryza sativa L.) roots and shoots under hydroponic conditions was investigated using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Rice plants were hydroponically exposed to positively, neutrally, and negatively charged AuNPs [AuNP1(+), AuNP2(0), AuNP3(−)] with a core diameter of 2 nm. Plants were exposed to AuNPs having 1.6 mg Au/L for 5 days or 0.14 mg Au/L for 3 months to elucidate how the surface charges of the nanoparticles affects their uptake into living plant tissues. The results demonstrate that terminal functional groups greatly affected the AuNP uptake into plant tissues. Au concentration determined by LA-ICP-MS in 5 day treated rice roots followed this order: AuNP1(+) > AuNP2(0) > AuNP3(−) but this order was reversed for rice shoots, indicating preferential translocation of AuNP3(−). Bioimages revealed distributions of mesophyll and vascular AuNP dependent on organ or AuNP concentration.
Show more [+] Less [-]Enhanced degradation of 14C-HCB in two tropical clay soils using multiple anaerobic–aerobic cycles Full text
2013
Kengara, Fredrick Orori | Doerfler, Ulrike | Welzl, Gerhard | Rüth, Bernhard | Munch, Jean Charles | Schroll, Reiner
The aim of the study was to induce and enhance the degradation of hexachlorobenzene (HCB), a highly-chlorinated persistent organic pollutant, in two ecologically different tropical soils: a paddy soil (PS) and a non-paddy soil (FS). The degradation of HCB was enhanced using two anaerobic–aerobic cycles in model laboratory experiments. There was greater degradation of HCB in the PS (half-life of 224 days) relative to the FS (half-life of 286 days). It was further shown that soils amended with compost had higher metabolite concentrations relative to the non-amended soils. In the first cycle, there was little degradation of HCB in both soils. However, in the second cycle, there was enhanced mineralization in the PS under aerobic conditions, with the compost-treated samples showing higher mineralization. There was also extensive volatilization in both soils. The metabolite pattern revealed that the increased mineralization and volatilization was due to the formation of lower chlorinated benzenes.
Show more [+] Less [-]Short- and long-term temporal changes in soil concentrations of selected endocrine disrupting compounds (EDCs) following single or multiple applications of sewage sludge to pastures Full text
2013
Rhind, S.M. | Kyle, C.E. | Ruffie, H. | Calmettes, E. | Osprey, M. | Zhang, Z.L. | Hamilton, D. | McKenzie, C.
Temporal changes in soil burdens of selected endocrine disrupting compounds were determined following application to pasture of either sewage sludge or inorganic fertilizer. Soil polycyclic aromatic hydrocarbon and polychlorinated biphenyl concentrations were not altered. Changes in concentrations of diethylhexyl phthalate (DEHP) and PBDEs 47 and 99 differed with season but concentrations remained elevated for more than three weeks after application, when grazing animals are normally excluded from pasture. It is concluded that single applications of sewage sludge can increase soil concentrations of some, but not all classes of EDCs, possibly to concentrations sufficient to exert biological effects when different chemicals act in combination, but patterns of change depend on season and soil temperature. Analysis of soil from pasture subjected to repeated sludge applications, over 13 years, provided preliminary evidence of greater increases in soil burdens of all of the EDC groups measured, including all of the PBDE congeners measured.
Show more [+] Less [-]Anthropogenic contaminants in Indo-Pacific humpback and Australian snubfin dolphins from the central and southern Great Barrier Reef Full text
2013
Cagnazzi, Daniele | Fossi, Maria Cristina | Parra, Guido J. | Harrison, Peter L. | Maltese, Silvia | Coppola, Daniele | Soccodato, Alice | Bent, Michael | Marsili, Letizia
We present the first evidence of accumulation of organochlorine compounds (DDTs, PCBs, HCB) and polycyclic aromatic hydrocarbons (PAHs) in Indo-Pacific humpback and Australian snubfin dolphins from the central and southern Great Barrier Reef. These dolphins are considered by the Great Barrier Marine Park Authority to be high priority species for management. Analyses of biopsy samples, collected from free ranging individuals, showed PAHs levels comparable to those reported from highly industrialized countries. DDTs and HCB were found at low levels, while in some individuals, PCBs were above thresholds over which immunosuppression and reproductive anomalies occur. These results highlight the need for ongoing monitoring of these and other contaminants, and their potential adverse effects on dolphins and other marine fauna. This is particularly important given the current strategic assessment of the Great Barrier Reef World Heritage Area being undertaken by the Australian Government and the Queensland Government.
Show more [+] Less [-]Calibration and field evaluation of polar organic chemical integrative sampler (POCIS) for monitoring pharmaceuticals in hospital wastewater Full text
2013
Bailly, Emilie | Levi, Yves | Karolak, Sara
The Polar Organic Chemical Integrative Sampler (POCIS) is a new tool for the sampling of organic pollutants in water. We tested this device for the monitoring of pharmaceuticals in hospital wastewater. After calibration, a field application was carried out in a French hospital for six pharmaceutical compounds (Atenolol, Prednisolone, Methylprednisolone, Sulfamethoxazole, Ofloxacin, Ketoprofen).POCIS were calibrated in tap water and wastewater in laboratory conditions close to relevant environmental conditions (temperature, flow velocity). Sampling rates (Rs) were determined and we observed a significant increase with flow velocity and temperature. Whatever the compound, the Rs value was lower in wastewater and the linear phase of uptake was shorter.POCIS were deployed in a hospital sewage pipe during four days and the estimated water concentrations were close to those obtained with twenty-four hour composite samples.
Show more [+] Less [-]Dispersal of the radionuclide caesium-137 (137Cs) from point sources in the Barents and Norwegian Seas and its potential contamination of the Arctic marine food chain: Coupling numerical ocean models with geographical fish distribution data Full text
2013
Heldal, Hilde Elise | Vikebø, Frode | Johansen, Geir Odd
Dispersal of 137Cs from the nuclear submarine wrecks Komsomolets and K-159, which are resting on the seabed in the Norwegian and Barents Seas, respectively, is simulated using realistic rates and hypothetical scenarios. Furthermore, spatiotemporal 137Cs concentrations in Northeast Arctic cod and capelin are estimated based on survey data. The results indicate that neither continuous leakages nor pulse discharges will cause concentrations of 137Cs in cod muscle or whole body capelin exceeding the intervention level of 600 Bq/kg fw. Continuous leakages from Komsomolets and K-159 and pulse discharges from Komsomolets induced negligible activity concentrations in cod and capelin. A pulse discharge of 100% of the 137Cs-inventory of K-159 will, however, result in concentrations in muscle of cod of above 100 times the present levels in the eastern Barents Sea. Within three years after the release, 137Cs levels above 20 Bq/kg fw in cod are no longer occurring in the Barents Sea.
Show more [+] Less [-]Interactions of tetracycline with Cd (II), Cu (II) and Pb (II) and their cosorption behavior in soils Full text
2013
Zhao, Yanping | Tan, Yinyue | Guo, Yong | Gu, Xueyuan | Wang, Xiaorong | Zhang, Yan
Tetracycline (TC), a common antibiotic, can behave as an efficient ligand with cations, but the effect of its interaction with heavy metal cations on the mobility of both species in soils has not been well evaluated. In this study, the complexation affinities of TC with Cd (II), Cu (II) and Pb (II) were examined using potentiometric titration and spectroscopic methods. The cosorption behavior of TC and metal ions onto three selected Chinese soils was evaluated using batch adsorption experiments. The presence of metal cations promoted TC adsorption through an ion bridging effect in the order Cu (II) > Pb (II) > Cd (II), which is in accordance with their complexation ability with TC. The addition of TC affects metal adsorption differently depending on the solution pH and metal type. Therefore, it is necessary to consider the complexation ability of TC and divalent metal cations when evaluating their mobility in soils.
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