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Why air quality in the Alps remains a matter of concern. The impact of organic pollutants in the alpine area Full text
2014
Schroeder, P. | Belis, C. A. | Schnelle-Kreis, J. | Herzig, R. | Prevot, A. S. H. | Raveton, M. | Kirchner, M. | Catinon, M.
In the middle of Europe, the Alps form a geographical and meteorological trap for atmospheric pollutants including volatile and semi-volatile organic compounds emitted in the surrounding lowlands. This is due to their barrier effects, high precipitation rates, and low ambient temperatures. Also the pollutants emitted in the cities inside the Alps spread in the region depending on orographic and meteorological conditions. Although a number of studies on the distribution and effect of pollutants in the Alps has been published, comprehensive information on potential hazards, and ways to improve this sensible environment are lacking. This opinion paper is the result of a discussion during the Winterseminar of the AlpsBioCluster project in Munich. It summarizes the current literature and presents some case studies on local pollution sources in the Alps, and the possibility of using biomonitoring techniques to assess critical pollution loads and distributions.
Show more [+] Less [-]Organotin compounds in surface sediments of the Southern Baltic coastal zone: a study on the main factors for their accumulation and degradation Full text
2014
Filipkowska, Anna | Kowalewska, Grażyna | Pavoni, Bruno
Sediment samples were collected in the Gulf of Gdańsk, and the Vistula and Szczecin Lagoons—all located in the coastal zone of the Southern Baltic Sea—just after the total ban on using harmful organotins in antifouling paints on ships came into force, to assess their butyltin and phenyltin contamination extent. Altogether, 26 sampling stations were chosen to account for different potential exposure to organotin pollution and environmental conditions: from shallow and well-oxygenated waters, shipping routes and river mouths, to deep and anoxic sites. Additionally, the organic carbon content, pigment content, and grain size of all the sediment samples were determined, and some parameters of the near-bottom water (oxygen content, salinity, temperature) were measured as well. Total concentrations of butyltin compounds ranged between 2 and 182 ng Sn g⁻¹d.w., whereas phenyltins were below the detection limit. Sediments from the Gulf of Gdańsk and Vistula Lagoon were found moderately contaminated with tributyltin, whereas those from the Szczecin Lagoon were ranked as highly contaminated. Butyltin degradation indices prove a recent tributyltin input into the sediments adjacent to sites used for dumping for dredged harbor materials and for anchorage in the Gulf of Gdańsk (where two big international ports are located), and into those collected in the Szczecin Lagoon. Essential factors affecting the degradation and distribution of organotins, based on significant correlations between butyltins and environmental variables, were found in the study area.
Show more [+] Less [-]Distinct diversity of the czcA gene in two sedimentary horizons from a contaminated estuarine core Full text
2014
Kaci, Assia | Petit, Fabienne | Lesueur, Patrick | Boust, Dominique | Vrel, Anne | Berthe, Thierry
In estuarine ecosystems, trace metals are mainly associated with fine grain sediments which settle on mudflats. Over time, the layers of sediments accumulate and are then transformed by diagenetic processes, recording the history of the estuary’s chemical contamination. In such a specific environment, we investigated to what extent a chronic exposure to contaminants could affect metal-resistant sedimentary bacteria in subsurface sediments. The occurrence and diversity of cadmium resistance genes (cadA, czcA) was investigated in 5- and 33-year-old sediments from a highly contaminated estuary (Seine France). Primers were designed to detect a 252-bp fragment of the czcA gene, specifically targeting a transmembrane helice domain (TMH IV) involved in the proton substrate antiport of this efflux pump. Although the cadA gene was not detected, the highest diversity of the sequence of the czcA gene was observed in the 5-year-old sediment. According to the percentage of identity at the amino acid level, the closest CzcA relatives were identified among Proteobacteria (α, β, γ, and δ), Verrucomicrobia, Nitrospirae, and Bacteroidetes. The most abundant sequences were affiliated with Stenotrophomonas. In contrast, in the 33-year-old sediment, CzcA sequences were mainly related to Rhodanobacter thiooxydans and Stenotrophomonas, suggesting a shaping of the metal-resistant microbial communities over time by both diagenetic processes and trace metal contamination.
Show more [+] Less [-]Specificity of metal tolerance and use of excluder metallophytes for the phytostabilization of metal polluted soils: the case of Silene paradoxa L Full text
2014
Colzi, Ilaria | Rocchi, Sonia | Rangoni, Mattia | Del Bubba, Massimo | Gonnelli, Cristina
This work was planned for providing useful information about the use of excluder metallophytes for phytostabilization of soils contaminated also with elements scarcely represented in the metalliferous environment of origin. To this aim, we investigated tolerance and accumulation of several different elements in a metallicolous and a nonmetallicolous population of Silene paradoxa through a hydroponic experiment. S. paradoxa metallicolous population showed increased tolerance not only to all the metals highly represented in the environment of origin but also to some of those scarcely present. Therefore, our results deposed in favor of the occurrence of the co-tolerance phenomenon in S. paradoxa for some elements. Metal accumulation was higher in the roots than in the shoots and lower in the metallicolous population than in the nonmetallicolous one, thus showing tolerance mechanisms to be based largely on metal exclusion. Anyway, the relative contribution of avoidance and of internal tolerance to metal tolerance was shown to be element-dependent. Present data revealed that metallicolous plants can effectively posses metal co-tolerances, which deserve to be investigated; as such, plants can actually represent a precious and exploitable tool also for the phytostabilization of soils contaminated with elements underrepresented in the environment of their origin.
Show more [+] Less [-]Variation of surface ozone in Campo Grande, Brazil: meteorological effect analysis and prediction Full text
2014
Pires, J. C. M. | Souza, A. | Pavão, H. G. | Martins, F. G.
The effect of meteorological variables on surface ozone (O₃) concentrations was analysed based on temporal variation of linear correlation and artificial neural network (ANN) models defined by genetic algorithms (GAs). ANN models were also used to predict the daily average concentration of this air pollutant in Campo Grande, Brazil. Three methodologies were applied using GAs, two of them considering threshold models. In these models, the variables selected to define different regimes were daily average O₃ concentration, relative humidity and solar radiation. The threshold model that considers two O₃ regimes was the one that correctly describes the effect of important meteorological variables in O₃ behaviour, presenting also a good predictive performance. Solar radiation, relative humidity and rainfall were considered significant for both O₃ regimes; however, wind speed (dispersion effect) was only significant for high concentrations. According to this model, high O₃ concentrations corresponded to high solar radiation, low relative humidity and wind speed. This model showed to be a powerful tool to interpret the O₃ behaviour, being useful to define policy strategies for human health protection regarding air pollution.
Show more [+] Less [-]Oxidation of polycyclic aromatic hydrocarbons by horseradish peroxidase in water containing an organic cosolvent Full text
2014
Chen, Zeyou | Li, Hui | Peng, Anping | Gao, Yanzheng
Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants that are toxic, mutagenic, and carcinogenic. We investigated the horseradish peroxidase (HRP)-catalyzed oxidation of PAHs in water containing N,N-dimethylformamide. Four PAHs (anthracene, phenanthrene, pyrene, and fluoranthene) were investigated using single-PAH and mixed-PAH systems. The results provide useful information regarding the preferential oxidation of anthracene over other PAHs regardless of the reaction time, enzyme dosage, and hydrogen peroxide concentration. The removal of PAHs was found to be very strongly correlated with the ionization potential (IP), and much greater PAH oxidation was observed at a lower IP. The oxidation of anthracene was specifically pH- and temperature-dependent, with the optimal pH and temperature being 8.0 and 40 °C, respectively. The redox mediators 1-hydroxybenzotriazole and veratryl alcohol promoted the transformation of anthracene by HRP; 9,10-anthraquinone was the main product detected from the anthracene oxidation system. The results of this study not only provide a better understanding of the oxidation of PAHs by utilizing a plant biocatalyst, but also provide a theoretical basis for establishing the HRP-catalyzed treatment of PAH-contaminated wastewater.
Show more [+] Less [-]Metabolic enzymes activity and histomorphology in the liver of whitefish (Coregonus lavaretus L.) and pike (Esox lucius L.) inhabiting a mineral contaminated lake Full text
2014
Churova, Maria V. | Murzina, Svetlana A. | Meshcheryakova, Olga V. | Nemova, Nina N.
The effects of wastewater from a mining and ore-dressing mill on fish in Lake Kostomukshskoe, which is used as a cesspool of circulating water and for storage of industrial wastes produced by the Kostomuksha mining and ore-dressing mill in northwest Russia, were studied. The lake is characterized by heavy mineralization, high pH, elevated levels of K⁺, Li⁺, SO₄²⁻, NO²⁻, Cl⁻, Li, Mn, and Ni, and the presence of a fine-dispersed mechanical suspension. To assess the impact of contamination on fish and determine the mechanisms of their adaptation, we investigated the biochemical indices and histology of the liver of whitefish (Coregonus lavaretus L.) and pike (Esox lucius L.) inhabiting Lake Kostomukshskoe, downstream Lake Koyvas (64° 47′ 30° 59′), and Lake Kamennoe, which is located in a nature preserve and has not been affected by anthropogenic activity (64° 28′ 30° 13′). Changes were detected in the activity of metabolic enzymes (cytochrome c oxidase (COX), lactate dehydrogenase, and glucose-6-phosphate dehydrogenase) in the liver. Specifically, the COX activity in the liver of both fish species from the contaminated lake decreased, indicating a low level of aerobic metabolism. Lipid infiltration was the most visible and widespread change observed in the liver of both fish species; therefore, it can be considered a marker of such long-term contamination. Lesions in pike liver demonstrated a wider range of severity than in those of whitefish. In summary, metabolic enzyme activity and histomorphology of the liver of whitefish and pike differed among lakes in a species-specific manner. The changes in enzyme activity and histomorphological alterations in fish that were observed can be applied for evaluation of freshwater systems that may be subjected to mineral pollution.
Show more [+] Less [-]Does energy consumption contribute to environmental pollutants? evidence from SAARC countries Full text
2014
Akhmat, Ghulam | Zaman, Khalid | Shukui, Tan | Irfan, Danish | Khan, Muhammad Mushtaq
The objective of the study is to examine the causal relationship between energy consumption and environmental pollutants in selected South Asian Association for Regional Cooperation (SAARC) countries, namely, Bangladesh, India, Nepal, Pakistan, and Srilanka, over the period of 1975–2011. The results indicate that energy consumption acts as an important driver to increase environmental pollutants in SAARC countries. Granger causality runs from energy consumption to environmental pollutants, but not vice versa, except carbon dioxide (CO₂) emissions in Nepal where there exists a bidirectional causality between CO₂ and energy consumption. Methane emissions in Bangladesh, Pakistan, and Srilanka and extreme temperature in India and Srilanka do not Granger cause energy consumption via both routes, which holds neutrality hypothesis. Variance decomposition analysis shows that among all the environmental indicators, CO₂ in Bangladesh and Nepal exerts the largest contribution to changes in electric power consumption. Average precipitation in India, methane emissions in Pakistan, and extreme temperature in Srilanka exert the largest contribution.
Show more [+] Less [-]Release of agronomical nutrient from zeolitite substrate containing phosphatic waste Full text
2014
Lancellotti, I. | Toschi, T. | Passaglia, E. | Barbieri, L.
The principal plant nutrients are phosphorous, nitrogen and potassium. Among these compounds, phosphorous is the most critical: it reacts rapidly, becoming an insoluble compound. The combination of zeolitites with phosphate materials (zeoponic substrate) agrees to a gradual and controlled phosphorous release in soils: phosphorous for plant uptake is released by the combination of dissolution and ion-exchange reactions. Animal bone ashes, rich in phosphorous and leached alone, release little amounts of soluble phosphorous and a great deal of alkaline sodium and potassium. Concerning chabazitic-zeolitite, it encourages a both gradual and growing soluble phosphorous release from animal bone ashes, in accordance with clinoptilolitic- and phillipsitic-zeolitite abilities; in particular, that release increases, thanks to both a higher zeolitite/bone ash ratio and ammonium enrichment of zeolitite. The use of zeolitite is environmentally sustainable in Italy because large amounts of deposits of zeolitite were present in Italy.
Show more [+] Less [-]Distribution of PCDD/Fs and dioxin-like PCBs in sediment and plants from a contaminated salt marsh (Tejo estuary, Portugal) Full text
2014
Nunes, Margarida | Vernisseau, Anaïs | Marchand, Philippe | Le Bizec, Bruno | Ramos, Fernando | Pardal, Miguel A.
Concentrations and profiles of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) were investigated in sediment and plants collected from a salt marsh in the Tejo estuary, Portugal. The highest PCDD/F and dl-PCB concentrations were detected in uncolonized sediments, averaging 325.25 ± 57.55 pg g⁻¹dry weight (dw) and 8,146.33 ± 2,142.14 pg g⁻¹dw, respectively. The plants Sarcocornia perennis and Halimione portulacoides growing in PCDD/F and dl-PCB contaminated sediments accumulated contaminants in roots, stems, and leaves. It was observed that PCDD/F and dl-PCB concentrations in roots were significantly lower in comparison with stems and leaves. In general, concentration of ΣPCDD/Fs and Σdl-PCBs in H. portulacoides tissues were found to be twofold higher than those in S. perennis, indicating a difference in the accumulation capability of both species. Furthermore, congener profiles changed between sediments and plant tissues, reflecting a selective accumulation of low chlorinated PCDD/Fs and non-ortho dl-PCBs in plants.
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