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Distributions and impact factors of antimony in topsoils and moss in Ny-Ålesund, Arctic Texto completo
2012
Jia, Nan | Sun, Liguang | He, Xin | You, Kehua | Zhou, Xin | Long, Nanye
The distribution of antimony (Sb) in topsoil and moss (Dicranum angustum) in disturbed and undisturbed areas, as well as coal and gangue, in Ny-Ålesund, Arctic was examined. Results show that the weathering of coal bed could not contribute to the increase of Sb concentrations in topsoil and moss in the study area. The distribution of Sb is partially associated with traffic and historical mining activities. The occurrence of the maximum Sb concentration is due to the contribution of human activities. In addition, the decrease of Sb content in topsoil near the coastline may be caused by the washing of seawater. Compared with topsoils, moss could be a useful tool for monitoring Sb in both highly and lightly polluted areas.
Mostrar más [+] Menos [-]Tissue-specific assimilation, depuration and toxicity of nickel in Mytilus edulis Texto completo
2012
Millward, Geoffrey E. | Kadam, Sandeep | Jha, Awadhesh N.
The tissue-specific accumulation and time-dependent depuration of radioactive ⁶³Ni by the byssus, gut, foot, gills, kidney, adductor muscle and faeces of Mytilus edulis has been investigated using a pulse-chase technique. The rate and extent of depuration of ⁶³Ni varied between tissues and, after 168 h, the concentration factors and assimilation efficiencies ranged from 1 to 35 L kg⁻¹ and 5%–13%, respectively. Mussels were also exposed to a range of environmentally-realistic concentrations of dissolved Ni, prior to the analysis of biological endpoints. The clearance rate was concentration-dependent and at the highest concentration decreased by 30%. Neutral red retention (NRR) assays indicated a cytotoxic response and DNA strand breaks were observed in the haemocytes. The association of DNA damage with that of physiological and cytotoxic effects suggests that Ni exerts a significant impact on Mytilus edulis at cellular and genetic levels.
Mostrar más [+] Menos [-]Reduced soil water availability did not protect two competing grassland species from the negative effects of increasing background ozone Texto completo
2012
Wagg, Serena | Mills, Gina | Hayes, Felicity | Wilkinson, Sally | Cooper, David | Davies, William J.
Two common (semi-) natural temperate grassland species, Dactylis glomerata and Ranunculus acris, were grown in competition and exposed to two watering regimes: well-watered (WW, 20–40% v/v) and reduced-watered (RW, 7.5–20% v/v) in combination with eight ozone treatments ranging from pre-industrial to predicted 2100 background levels. For both species there was a significant increase in leaf damage with increasing background ozone concentration. RW had no protective effect against increasing levels of ozone-induced senescence/injury. In high ozone, based on measurements of stomatal conductance, we propose that ozone influx into the leaves was not prevented in the RW treatment, in D. glomerata because stomata were a) more widely open than those in less polluted plants and b) were less responsive to drought. Total seasonal above ground biomass was not significantly altered by increased ozone; however, ozone significantly reduced root biomass in both species to differing amounts depending on watering regime.
Mostrar más [+] Menos [-]Multicorrelation models and uptake factors to estimate extractable metal concentrations from soil and metal in plants in pasturelands fertilized with manure Texto completo
2012
Lopes, Carla | Herva, Marta | Franco-Uría, Amaya | Roca, Enrique
Multicorrelation models and uptake factors to estimate extractable metal concentrations from soil and metal in plants in pasturelands fertilized with manure Texto completo
2012
Lopes, Carla | Herva, Marta | Franco-Uría, Amaya | Roca, Enrique
Environmental risk assessment (ERA) is a useful methodology to estimate the possible adverse effects to human health due to contaminants exposure. In the case of agricultural scenarios, this method requires knowing the concentrations of contaminants in soil solution and vegetation, among other parameters. This study aimed to develop multicorrelation models to estimate metal extractable from soil as a function of total metal concentration in soil and soil properties in a cattle manure application scenario. It also aimed to estimate metal concentrations in plant by soil–plant uptake factors (UF). All the multicorrelation models obtained were significant, ranging R² values from 0.44 for Cd to 0.92 for Cu. Soil–plant UF were an adequate method for the estimation of metal concentration in plant, since the relationship between the soil–plant UF and the extractable metal concentration from soil was significantly described by a power model, for all the heavy metals.
Mostrar más [+] Menos [-]Multicorrelation models and uptake factors to estimate extractable metal concentrations from soil and metal in plants in pasturelands fertilized with manure Texto completo
2012
Lopes, Carla | Herva, Marta | Franco-Uría, A. | Roca, Enrique
6 páginas, 1 figura, 3 tablas | Environmental risk assessment (ERA) is a useful methodology to estimate the possible adverse effects to human health due to contaminants exposure. In the case of agricultural scenarios, this method requires knowing the concentrations of contaminants in soil solution and vegetation, among other parameters. This study aimed to develop multicorrelation models to estimate metal extractable from soil as a function of total metal concentration in soil and soil properties in a cattle manure application scenario. It also aimed to estimate metal concentrations in plant by soil–plant uptake factors (UF). All the multicorrelation models obtained were significant, ranging R2 values from 0.44 for Cd to 0.92 for Cu. Soil–plant UF were an adequate method for the estimation of metal concentration in plant, since the relationship between the soil–plant UF and the extractable metal concentration from soil was significantly described by a power model, for all the heavy metals. | This work has been supported by the Spanish Government (Science and Innovation Ministry) through the Project INDIE (CTM2010-18893) ERDF included. Marta Herva wishes to thank the University of Santiago de Compostela for her pre-doctoral contract. Dr. Amaya Franco-Uría would like to thank MICINN for the support provided by the ‘‘Juan de la Cierva” Subprogram. | Peer reviewed
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean Sea: Atmospheric occurrence, deposition and decoupling with settling fluxes in the water column Texto completo
2012
Castro-Jiménez, Javier | Berrojalbiz, Naiara | Wollgast, Jan | Dachs, Jordi
∑₃₀PAH gas phase concentrations (13–86 and 22–40 ng m⁻³ in the Mediterranean and Black Seas, respectively) dominated the atmospheric levels due to the high contribution of phenanthrene, dibenzothiophene and their alkylated derivates. The high variability of PAH atmospheric concentrations in the different sub-basins is due to several factors (i.e. air-mass trajectory, proximity to sources and losses by deposition). The ∑₃₀PAH atmospheric deposition (dominated by low MW PAH net air–water diffusive fluxes) is estimated to be ∼3100 ton y⁻¹ (Mediterranean) and ∼500 ton y⁻¹ (Black Sea). Net volatilization for certain PAHs was estimated. Deposition fluxes (1–2 orders of magnitude higher than reported PAH settling fluxes in the water column) confirm an important depletion/sink of water column PAH in the photic zone, especially for low MW PAHs. Degradation processes in the water column may be responsible for this decoupling. Conversely, high MW PAHs dry deposition fluxes are similar to their settling fluxes.
Mostrar más [+] Menos [-]Atmospheric fate of poly- and perfluorinated alkyl substances (PFASs): II. Emission source strength in summer in Zurich, Switzerland Texto completo
2012
Wang, Zhanyun | Scheringer, Martin | Macleod, Matthew | Bogdal, Christian | Müller, Claudia E. | Gerecke, Andreas C. | Hungerbühler, Konrad
Fluorotelomer alcohols (FTOHs) and perfluorooctane sulfonamides (FOSAs) are present in consumer products and are semi-volatile precursors of persistent perfluoroalkyl acids (PFAAs). The high variability of levels of FTOHs and FOSAs in products makes it difficult to derive FTOH- and FOSA-emissions from urban areas based on emission factors. Here we used a multimedia mass balance model that describes the day–night cycle of semi-volatile organic chemicals in air to interpret measurements of 8:2 FTOH, 10:2 FTOH, MeFOSA and EtFOSA from a sampling campaign in summer 2010 in Zurich, Switzerland. The estimated emission source strength of the four substances follows the sequence: 8:2 FTOH (2.6 g/h) > 10:2 FTOH (0.75 g/h) > MeFOSA (0.08 g/h) > EtFOSA (0.05 g/h). There is no FTOHs- or FOSAs-related industry in Zurich. Accordingly, our estimates are representative of diffusive emissions during use and disposal of consumer products, and describe noticeable sources of these PFASs to the environment.
Mostrar más [+] Menos [-]Depleted soil carbon and nitrogen pools beneath impervious surfaces Texto completo
2012
Raciti, Steve M. | Hutyra, Lucy R. | Finzi, Adrien C.
Urban soils and vegetation contain large pools of carbon (C) and nitrogen (N) and may sequester these elements at considerable rates; however, there have been no systematic studies of the composition of soils beneath the impervious surfaces that dominate urban areas. This has made it impossible to reliably estimate the net impact of urbanization on terrestrial C and N pools. In this study, we compared open area and impervious-covered soils in New York City and found that the C and N content of the soil (0–15 cm) under impervious surfaces was 66% and 95% lower, respectively. Analysis of extracellular enzyme activities in the soils suggests that recalcitrant compounds dominate the organic matter pool under impervious surfaces. If the differences between impervious-covered and open area soils represent a loss of C and N from urban ecosystems, the magnitude of these losses could offset sequestration in other parts of the urban landscape.
Mostrar más [+] Menos [-]Relevance of aerosol size spectrum analysis as support to qualitative source apportionment studies Texto completo
2012
Manigrasso, M. | Febo, A. | Guglielmi, F. | Ciambottini, V. | Avino, P.
This work presents a diagnostic methodology in support to source apportionment studies to identify remote and local pollution sources. It is based on the temporal analysis of both PM size distributions and PM size fraction correlation along with natural radioactivity measurements as index of Planetary Boundary Layer dynamic. A correlation drop is indicative of changing aerosol sources. When this observation is coupled with decreasing level of natural radioactivity and increasing aerosol concentration, be it coarse or fine, it is indicative of the inflow of remote polluted air masses. The methodology defines in which size range operates the contribution of remote pollution sources. It was applied to two PM10 pollution episodes: the first involved the advection of coarse PM, the second entailed the inflow of two air masses, one transporting coarse dust and the other fine PM. Dust models and backward trajectories analysis confirmed such results, indicating the air mass provenience.
Mostrar más [+] Menos [-]Sorption kinetics of ofloxacin in soils and mineral particles Texto completo
2012
Pan, Bo | Wang, Peng | Wu, Min | Li, Jing | Zhang, Di | Xiao, Di
The environmental behavior of antibiotics is not well known and the precise environmental risk assessment is not practical. This study investigated the sorption kinetics of ofloxacin, a widely used antibiotics, on soil particles with different organic carbon contents as well as soil components (a humic acid, ferric oxide and kaolinite). Two-compartment sorption kinetics were mathematically recognized (except ferric oxide because of its very fast sorption). The apparent sorption rate and the contribution of fast sorption compartment decreased with the increased organic carbon content with the exception of humic acid, suggesting that the slow sorption sites were partially located in organo-mineral complex. The OFL concentration-dependent sorption kinetics suggested that the slow sorption compartment was not controlled by diffusion process as indicated by slower sorption at higher OFL loading. The difference between OFL sorption kinetics and those of hydrophobic organic contaminants was discussed and possible mechanism of OFL two-compartment sorption was proposed.
Mostrar más [+] Menos [-]Building materials. VOC emissions, diffusion behaviour and implications from their use Texto completo
2012
Katsoyiannis, Athanasios | Leva, Paolo | Barrero-Moreno, Josefa | Kotzias, Dimitrios
Five cement- and five lime-based building materials were examined in an environmental chamber for their emissions of Volatile Organic Compounds (VOCs). Typical VOCs were below detection limits, whereas not routinely analysed VOCs, like neopentyl glycol (NPG), dominated the cement-based products emissions, where, after 72 h, it was found to occur, in levels as high as 1400 μg m⁻³, accounting for up to 93% of total VOCs. The concentrations of NPG were not considerably changed between the 24 and 72 h of sampling. The permeability of building materials was assessed through experiments with a dual environmental chamber; it was shown that building materials facilitate the diffusion of chemicals through their pores, reaching equilibrium relatively fast (6 h).
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