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Mercury in compact fluorescent lamps (CFLs): European legislation introduces an avoidable analytical bias النص الكامل
2014
Steinhauser, Georg | Stettner, Christoph | Foster, Michaela
European legislation has set a limit of 5 mg Hg per compact fluorescent lamp (CFL). Compliance with this regulation is tested with a method given in a European law from 2002 (“EU method”). According to the EU method, the arc tube has to be placed inside a fume cupboard and cut into segments. These pieces are collected and washed with HNO₃, which is finally analyzed for Hg. In this study, we investigated the losses of Hg via the gas phase, which are ignored by the EU method, using a semiquantitative radiochemical neutron activation analysis (RNAA) technique developed at the TRIGA Mark II reactor in Vienna (Austria). Depending on the product, the losses range as high as approximately 2 % at 20 °C. At higher ambient temperatures (hot summer days), the losses may increase by a factor of 4. Quality products generally suffer lower emission via the gas phase than cheap products, which is probably due to amalgam or other techniques that retain the Hg from broken CFLs. In any case, the EU method introduces a small but avoidable systematic error into the analysis and, in contrast to recommended practices, underestimates the Hg content of the CFL in question. Having technical alternatives at hand, we urge European lawmakers to adjust the law accordingly.
اظهر المزيد [+] اقل [-]Cell-programmed death induced by walnut husk washing waters in three horticultural crops النص الكامل
2014
Petriccione, Milena | Papa, Stefania | Ciniglia, Claudia
Walnut husk washing waters (WHWW), a by-product of walnut production, are indiscriminately used for irrigation without preliminary risk assessment. Basing on previous in vitro results on the toxicity of this by-product, we have followed the morphophysiological development of Zea mays, Lactuca sativa cv. Gentilina and L. sativa cv. Canasta under diluted and undiluted WHWW irrigation. Significant development alterations have been observed in root and shoot elongations for all crops as well as in total biomass and chlorophyll content. The genotoxic potential of WHWW has been concurrently verified; acridine orange/ethidium bromide staining evidenced chromatin modifications and DNA degradation and also was confirmed by DNA laddering. The DNA instability was also assessed through RAPD, thus suggesting the danger of the by-product of walnut processing and focusing the attention on the necessity of an efficient treatment of WHWWs. The findings obtained by PCA of agronomic and physiological traits suggested that establishing guidelines for the administration of WHWW for irrigation is of great importance, and it is necessary to supervise their use in agricultural soils.
اظهر المزيد [+] اقل [-]Discovery of characteristic molecular signatures for the simultaneous prediction and detection of environmental pollutants النص الكامل
2014
Song, Mi-Kyung | Choi, Han-Seam | Park, Yong-Keun | Ryu, Jae-Chun
Gene expression data may be very promising for the classification of toxicant types, but the development and application of transcriptomic-based gene classifiers for environmental toxicological applications are lacking compared to the biomedical sciences. Also, simultaneous classification across a set of toxicant types has not been investigated extensively. In the present study, we determined the transcriptomic response to three types of ubiquitous toxicants exposure in two types of human cell lines (HepG2 and HL-60), which are useful in vitro human model for evaluation of toxic substances that may affect human hepatotoxicity (e.g., polycyclic aromatic hydrocarbon [PAH] and persistent organic pollutant [POP]) and human leukemic myelopoietic proliferation (e.g., volatile organic compound [VOC]). The findings demonstrate characteristic molecular signatures that facilitated discrimination and prediction of the toxicant type. To evaluate changes in gene expression levels after exposure to environmental toxicants, we utilized 18 chemical substances; nine PAH toxicants, six VOC toxicants, and three POP toxicants. Unsupervised gene expression analysis resulted in a characteristic molecular signature for each toxicant group, and combination analysis of two separate multi-classifications indicated 265 genes as surrogate markers for predicting each group of toxicants with 100 % accuracy. Our results suggest that these expression signatures can be used as predictable and discernible surrogate markers for detection and prediction of environmental toxicant exposure. Furthermore, this approach could easily be extended to screening for other types of environmental toxicants.
اظهر المزيد [+] اقل [-]Will urban expansion lead to an increase in future water pollution loads?—a preliminary investigation of the Haihe River Basin in northeastern China النص الكامل
2014
Dong, Yang | Liu, Yi | Chen, Jining
Urban expansion is a major driving force changing regional hydrology and nonpoint source pollution. The Haihe River Basin, the political, economic, and cultural center of northeastern China, has undergone rapid urbanization in recent decades. To investigate the consequences of future urban sprawl on nonpoint source water pollutant emissions in the river basin, the urban sprawl in 2030 was estimated, and the annual runoff and nonpoint source pollution in the Haihe River basin were simulated. The Integrated Model of Non-Point Sources Pollution Processes (IMPULSE) was used to simulate the effects of urban sprawl on nonpoint source pollution emissions. The outcomes indicated that the urban expansion through 2030 increased the nonpoint source total nitrogen (TN), total phosphorous (TP), and chemical oxygen demand (COD) emissions by 8.08, 0.14, and 149.57 kg/km², respectively. Compared to 2008, the total nonpoint emissions rose by 15.33, 0.57, and 12.39 %, respectively. Twelve percent of the 25 cities in the basin would increase by more than 50 % in nonpoint source TN and COD emissions in 2030. In particular, the nonpoint source TN emissions in Xinxiang, Jiaozuo, and Puyang would rise by 73.31, 67.25, and 58.61 %, and the nonpoint source COD emissions in these cities would rise by 74.02, 51.99, and 53.27 %, respectively. The point source pollution emissions in 2008 and 2030 were also estimated to explore the effects of urban sprawl on total water pollution loads. Urban sprawl through 2030 would bring significant structural changes of total TN, TP, and COD emissions for each city in the area. The results of this study could provide insights into the effects of urbanization in the study area and the methods could help to recognize the role that future urban sprawl plays in the total water pollution loads in the water quality management process.
اظهر المزيد [+] اقل [-]Plant growth promotion by inoculation with selected bacterial strains versus mineral soil supplements النص الكامل
2014
Wernitznig, S. | Adlassnig, W. | Sprocati, A. R. | Turnau, K. | Neagoe, A. | Alisi, C. | Sassmann, S. | Nicoara, A. | Pinto, V. | Cremisini, C. | Lichtscheidl, I.
In the process of remediation of mine sites, the establishment of a vegetation cover is one of the most important tasks. This study tests two different approaches to manipulate soil properties in order to facilitate plant growth. Mine waste from Ingurtosu, Sardinia, Italy rich in silt, clay, and heavy metals like Cd, Cu, and Zn was used in a series of greenhouse experiments. Bacteria with putative beneficial properties for plant growth were isolated from this substrate, propagated and consortia of ten strains were used to inoculate the substrate. Alternatively, sand and volcanic clay were added. On these treated and untreated soils, seeds of Helianthus annuus, of the native Euphorbia pithyusa, and of the grasses Agrostis capillaris, Deschampsia flexuosa and Festuca rubra were germinated, and the growth of the seedlings was monitored. The added bacteria established well under all experimental conditions and reduced the extractability of most metals. In association with H. annuus, E. pithyusa and D. flexuosa bacteria improved microbial activity and functional diversity of the original soil. Their effect on plant growth, however, was ambiguous and usually negative. The addition of sand and volcanic clay, on the other hand, had a positive effect on all plant species except E. pithyusa. Especially the grasses experienced a significant benefit. The effects of a double treatment with both bacteria and sand and volcanic clay were rather negative. It is concluded that the addition of mechanical support has great potential to boost revegetation of mining sites though it is comparatively expensive. The possibilities offered by the inoculation of bacteria, on the other hand, appear rather limited.
اظهر المزيد [+] اقل [-]Continental bottled water assessment by stir bar sorptive extraction followed by gas chromatography-tandem mass spectrometry (SBSE-GC-MS/MS) النص الكامل
2014
Guart, Albert | Calabuig, Ignazio M. | Lacorte, Silvia | Borrell, Antonio
This study was aimed to determine the presence of 69 organic contaminants in 77 representative bottled waters collected from 27 countries all over the world. All water samples were contained in polyethylene terephthalate bottles. Target compounds were (1) environmental contaminants (including 13 polycyclic aromatic hydrocarbons (PAHs), 31 pesticides including organochlorine (OCPs), organophosphorus, and pyrethroids; 7 polychlorinated biphenyls (PCBs); and 7 triazines) and (2) plasticizers (including 6 phthalates and 5 other compounds). Samples were analyzed by stir bar sorptive extraction followed by gas chromatography-tandem mass spectrometry. PAHs, OCPs, PCBs, and triazines, which are indicators of groundwater pollution, were not detected in most of the samples, except for naphthalene (0.005–0.202 μg/L, n = 16). On the other hand, plastic components were detected in 77 % of the samples. Most frequently detected compounds were dimethyl phthalate and benzophenone at concentrations of 0.005–0.125 (n = 41) and 0.014–0.921 (n = 32), respectively. Levels detected are discussed in terms of contamination origin and geographical distribution. Target compounds were detected at low concentrations. Results obtained showed the high quality of bottled water in the different countries around the world.
اظهر المزيد [+] اقل [-]Spatial extraction model for soil environmental quality of anomalous areas in a geographic scale النص الكامل
2014
Yang, Chunlin | Guo, Ruiping | Wu, Zhifeng | Zhou, Kai | Yue, Qingling
An approach to establish a soil environmental assessment model was proposed to evaluate the soil environmental quality level. The kriging technique and a self-organizing map (SOM) were integrated to investigate the soil environmental quality in a geographic information system (GIS). In this study, SOM was applied to categorize the data set of nine heavy metals in topsoil. A total of 261 topsoil samples were collected to determine the concentrations of Cu, Pb, Zn, Cd, Ni, Cr, Hg, As, and Mn. The samples were clustered into three classes by SOM and visualized by GIS. The results show that different environmental quality categories are significantly different and that the soil environmental quality assessment model is effective.
اظهر المزيد [+] اقل [-]Framing environmental problems: Problem entrepreneurs and the issue of water pollution from agriculture in Brittany, 1970-2005 النص الكامل
2014
Bourblanc M.
Framing environmental problems: Problem entrepreneurs and the issue of water pollution from agriculture in Brittany, 1970-2005 النص الكامل
2014
Bourblanc M.
The claim that public problems are constructs is now widely recognized as justified and was first established in social problem theory. The high instability of problem definition activities in the case of water pollution coming from agriculture in Brittany demonstrates this particularly well. The objective of this article is to describe ways by which an environmental movement organization (EMO) conceives its activities of public problem construction. Inspired by social movement theory, but aiming at overcoming its weaknesses, the paper seeks to highlight the influence of EMO endogenous meaning production in problem construction processes, a dimension often overlooked even by framing theory. In a bid to support that claim, the paper shows the influence of the affective dimension over the strategic one within the problematization process. Forging a conceptual distinction characterized by a perceived problem and strategic definitions, the paper underlines the fundamental interrelated nature of these two components and consequently emphasizes the reciprocal dependence of the perceived problem over the strategic (either material or cognitive) definitions. Finally, the paper evokes the benefit and impact of this conceptual distinction on the policy-making process. (Résumé d'auteur)
اظهر المزيد [+] اقل [-]Framing Environmental Problems: Problem Entrepreneurs and the Issue of Water Pollution from Agriculture in Brittany, 1970–2005 النص الكامل
2014
Bourblanc, Magalie
The claim that public problems are constructs is now widely recognized as justified and was first established in social problem theory. The high instability of problem definition activities in the case of water pollution coming from agriculture in Brittany demonstrates this particularly well. The objective of this article is to describe ways by which an environmental movement organization (EMO) conceives its activities of public problem construction. Inspired by social movement theory, but aiming at overcoming its weaknesses, the paper seeks to highlight the influence of EMO endogenous meaning production in problem construction processes, a dimension often overlooked even by framing theory. In a bid to support that claim, the paper shows the influence of the affective dimension over the strategic one within the problematization process. Forging a conceptual distinction characterized by a perceived problem and strategic definitions, the paper underlines the fundamental interrelated nature of these two components and consequently emphasizes the reciprocal dependence of the perceived problem over the strategic (either material or cognitive) definitions. Finally, the paper evokes the benefit and impact of this conceptual distinction on the policy-making process.
اظهر المزيد [+] اقل [-]Biomarkers in the Siak River System, E. Sumatra, Indonesia النص الكامل
2014
Liebezeit, Gerd | Wöstmann, Ralf | Ziehe, Daniel
A total of 33 plant species and 122 surface sediments were obtained from March 2004 to November 2008 in the Siak River system including its major tributaries and coastal areas. Grain size distribution shows the sediments to be sands to silt with a general trend of coarser sediments in the upper reaches and fi ner ones in the estuary. The expected linear relationship between the content of organic carbon and the mud fraction of the sediments (<63 µm) is distorted by input of (a) clay-sized, organic-poor material from river bank erosion and (b) input of coarse plant detritus. All samples were analysed for n-alkanes and steroids. For all plant samples and a limited number of sediment samples, fatty acids were also determined. The data indicate a variety of organic carbon sources, the dominant one being river bank vegetation. Urban and industrial discharges, peat erosion and atmospheric deposition of black carbon and biomarkers might also play a role in controlling the lipid composition of the sedimentary organic carbon pool.
اظهر المزيد [+] اقل [-]Performance of the Arctic calanoid copepods Calanus glacialis and C. hyperboreus under elevated pCO2 and temperatures النص الكامل
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz-Josef
Performance of the Arctic calanoid copepods Calanus glacialis and C. hyperboreus under elevated pCO2 and temperatures النص الكامل
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz-Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10 days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and Calanus hyperboreus, at 0 °C at 390 and 3000 µatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10 °C). Incubation at 10 °C induced sublethal stress, which might have overruled effects of pCO2. At 5 °C and 3000 µatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
اظهر المزيد [+] اقل [-]Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus النص الكامل
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10 days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and C. hyperboreus, at 0 °C at 390 and 3000 µatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10 °C). Incubation at 10 °C induced sublethal stress, which might have overruled effects of pCO2. At 5 °C and 3000 µatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
اظهر المزيد [+] اقل [-]Long-term effects of elevated CO2 and temperature on the Arctic calanoid copepods Calanus glacialis and C. hyperboreus النص الكامل
2014
Hildebrandt, Nicole | Niehoff, Barbara | Sartoris, Franz Josef
The sensitivity of copepods to ocean acidification (OA) and warming may increase with time, however, studies >10days and on synergistic effects are rare. We therefore incubated late copepodites and females of two dominant Arctic species, Calanus glacialis and Calanushyperboreus, at 0°C at 390 and 3000μatm pCO2 for several months in fall/winter 2010. Respiration rates, body mass and mortality in both species and life stages did not change with pCO2. To detect synergistic effects, in 2011 C. hyperboreus females were kept at different pCO2 and temperatures (0, 5, 10°C). Incubation at 10°C induced sublethal stress, which might have overruled effects of pCO2. At 5°C and 3000μatm, body carbon was significantly lowest indicating a synergistic effect. The copepods, thus, can tolerate pCO2 predicted for a future ocean, but in combination with increasing temperatures they could be sensitive to OA.
اظهر المزيد [+] اقل [-]