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The Use of Natural Sorbents for Spilled Crude Oil and Diesel Cleanup from the Water Surface Full text
2014
Paulauskienė, T. | Jucikė, I. | Juščenko, N. | Baziukė, D.
Oil spills impose serious damage to the environment. A spilled crude oil or its products affect aquatic flora and fauna and influence the atmosphere as well. Such pollutants are especially dangerous for the water ecosystems, where biological self-purification processes are slower (for example the Baltic Sea), than in warmer regions. In this paper, we evaluate a sorption capacity of ecologically friendly natural sorbents, when the crude oil and diesel are spilled on the surface of water. The experiments are carried out in the laboratory, and the water from the Lithuanian Baltic Sea coastline and Curonian Lagoon is used. Moss, straw, wool, sawdust, and peat are the natural sorbents evaluated during the experiments. Chromatographic analysis of crude oil and diesel during the process of sorption was conducted as well. An experiment with some synthetic sorbents was carried out to compare the results with natural ones. The experiments showed that the most suitable material for crude oil or diesel fuel spilled on the water surface is peat. As well, Lagergren’s model was adopted to the case of the sorption processes we have investigated. It can be exploited as a decision support tool while deciding the required time interval to achieve maximum sorption capacity of the sorbent in use.
Show more [+] Less [-]Biosorption of Textile Dye by Aspergillus lentulus Pellets: Process Optimization and Cyclic Removal in Aerated Bioreactor Full text
2014
Kaushik, Prachi | Mishra, Abhishek | Malik, Anushree | Pant, Kamal Kishore
The present study was conducted to maximize the biosorption of dye by utilizing the native (untreated) pellets of Aspergillus lentulus. The native (55.0 mg/g) and heat-treated (56.7 mg/g) pellets showed excellent dye biosorption capacity which declined upon alginate immobilization (27.2 mg/g). Fourier transform infrared and EDX spectra revealed that phosphate and –CH₃groups are important in determining the biosorption capacity of the pretreated fungal biomass. The operating conditions of the aerated fed batch reactor were optimized and 90 % removal of Acid Blue 120 in 12 h was achieved after five biosorption–desorption cycles. At the end of the fifth cycle, 508.57 mg/L dye could be removed in 60 h with the removal rate of 8.48 mg/L/h. Further, the potential utilization of fungal biomass for the treatment of complex effluent was validated by studying the dye removal from unprocessed textile effluent wherein 58.0 % dye was removed within 4 h of contact.
Show more [+] Less [-]Effects of aluminium and bacterial lipopolysaccharide on oxidative stress and immune parameters in roach, Rutilus rutilus L Full text
2014
Jolly, S. | Jaffal, A. | Delahaut, L. | Palluel, O. | Porcher, J.-M. | Geffard, A. | Sanchez, W. | Betoulle, S.
Aluminium is used in diverse anthropogenic processes at the origin of pollution events in aquatic ecosystems. In the Champagne region (France), high concentrations of aluminium (Al) are detected due to vine-growing practices. In fish, little is known about the possible immune-related effects at relevant environmental concentrations. The present study analyzes the simultaneous effects of aluminium and bacterial lipopolysaccharide (LPS), alone and in combination, on toxicological biomarkers in the freshwater fish species Rutilus rutilus. For this purpose, roach treated or not with LPS were exposed to environmental concentrations of aluminium (100 μg/L) under laboratory-controlled conditions for 2, 7, 14 and 21 days. After each exposure time, we assessed hepatic lipoperoxidation, catalase activity, glutathione reductase activity and total glutathione content. We also analyzed cellular components related to the LPS-induced inflammatory response in possible target tissues, i.e. head kidney and spleen. Our results revealed a significant prooxidant effect in the liver cells and head kidney leukocytes of roach exposed to 100 μg of Al/L for 2 days. In liver, we observed more lipoperoxidation products and lower endogenous antioxidant activity levels such as glutathione reductase activity and total glutathione content. These prooxidant effects were associated with a higher oxidative burst in head kidney leukocytes, and they were all the more important in fish stimulated by LPS injection. These findings demonstrate that environmental concentrations of Al induce oxidative and immunotoxic effects in fish and are associated to an immunomodulatory process related to the inflammatory response.
Show more [+] Less [-]Spatial Risk Assessment of Farming on Wetland Habitats in Watershed System Full text
2014
Sekar, I. | Randhir, Timothy O.
Natural resource habitats, which are isolated from the surface water bodies, are often unregulated and face a higher risk of degradation. Vernal pools, habitats for amphibians, are vulnerable to external stressors that often lead to decline in biodiversity. There is a need to protect these through conservation measures at a spatially targeted level. This study is conducted in the Middle Connecticut River Watershed of Massachusetts State. We evaluate the risk faced by isolated vernal pools at the subwatershed scale. The assessment involves the impact of agricultural intensity and vernal pool distribution in proximity to agriculture parcels. This is performed using geoprocessing techniques within a geographic information system (GIS). The spatial data are used in a nonlinear regression model to evaluate potential stressors to vernal pool existence. The model included land use, geographic features, and hydrographic factors. Agriculture and open land positively influence vernal pool existence, because of vernal pool association with low-lying areas. In addition, elevation showed a negative influence on the number of vernal pool habitats. The results of the spatial risk evaluation of habitat are helpful to target efforts on specific subwatersheds in conserving vernal pool habitats.
Show more [+] Less [-]Efficient Removal of Dyes from Aqueous Solution by Mesoporous Nanocomposite Al2O 3/Ni 0.5Zn 0.5Fe 2O 4 Microfibers Full text
2014
Yang, Xinchun | Wang, Zhou | Jing, Maoxiang | Liu, Ruijiang | Jin, Lina | Shen, Xiangqian
A novel mesoporous, nanocomposite, magnetically separable adsorbent, namely activated alumina (γ-Al₂O₃)/ferrite (Ni₀.₅Zn₀.₅Fe₂O₄) microfibers have been successfully prepared by the sol–gel process. These nanocomposite γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers are formed after calcination of the precursor at 450 °C for 3 h, and characterized with high aspect ratios and uniform diameters of 1–10 μm. In the nanocomposite γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers, the spherical γ-Al₂O₃particles are homogeneously embedded on the microfiber. Their specific surface areas and magnetic properties are significantly influenced by the γ-Al₂O₃content and calcination conditions. With the designed γ-Al₂O₃mass fraction of 0.2 and the calcination temperature of 550 °C, the γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers possess a high specific surface area of 118.3 m²/g and saturation magnetization (Mₛ) of 20.4 Am² kg⁻¹, respectively. The adsorption behaviors of the nanocomposite γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers were examined using the Congo red and methyl blue dyes as the adsorbate. The adsorption kinetics, effects of the adsorbent dosage and solution pH, adsorption isotherms, and regeneration of the microfiber adsorbents were investigated. The pseudo-second-order model can be used to describe the adsorption kinetics. The resultant isotherm data are well fitted by the Temkin model, implying that the dyes adsorption on the γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers is a multilayer adsorption combined with some degrees of chemical interactions. Considering the simple synthesis process, high adsorption and unique magnetic property, these mesoporous, magnetic, nanocomposite γ-Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers can be used as a highly efficient, fast, and convenient adsorbent for dyes removal.Highlights The magnetic mesoporous Al₂O₃/Ni₀.₅Zn₀.₅Fe₂O₄microfibers were synthesized. Adsorption kinetics and adsorption isotherms were investigated. The separation, regeneration, and adsorption efficiency were enhanced.
Show more [+] Less [-]Effects of Emissions from an Aluminium Smelter in a Tree Tropical Species Sensitive to Fluoride Full text
2014
Sant’Anna-Santos, Bruno Francisco | Azevedo, Aristéa Alves | Alves, Thiago Gonçalves | Campos, Naiara Viana | Oliva, Marco Antônio | Valente, Vânia Maria Moreira
Effects of Emissions from an Aluminium Smelter in a Tree Tropical Species Sensitive to Fluoride Full text
2014
Sant’Anna-Santos, Bruno Francisco | Azevedo, Aristéa Alves | Alves, Thiago Gonçalves | Campos, Naiara Viana | Oliva, Marco Antônio | Valente, Vânia Maria Moreira
Fluoride is among the most phytotoxic atmospheric pollutants, commonly linked to the appearance of lesions in susceptible plants around emitting sources. In order to assess the effects of fluoride on leaves of Spondias dulcis Parkinson (Anacardiaceae), plants were examined 78 km (non-polluted area) and 0.78 km (polluted area) from an aluminium smelter. The level of fluoride increased with the exposure time of the plants in the polluted area. On the third day of exposure in the polluted area, necroses with typical colouration were observed. Micromorphological damage began at the abaxial epidermis, mainly associated with the stomata. Starch grain accumulation was more pronounced in the midrib. The cell membranes and chloroplasts were greatly affected by the pollutant. We observed accumulation of phenolic compounds and electron-dense material at the boundaries of the ending veinlets. The microscopic events described precede the appearance of symptoms and are therefore of prognostic value in predicting injury by fluoride and will be useful as biomarkers. The high sensitivity of S. dulcis to fluoride and the specificity of the symptoms confirm, for the first time, in an experiment of active biomonitoring, the potential of this species as a bioindicator.
Show more [+] Less [-]Effects of emissions from an aluminium smelter in a tree tropical species sensitive to fluoride Full text
2014
Sant’Anna-Santos, Bruno Francisco | Azevedo, Aristéa Alves | Alves, Thiago Gonçalves | Campos, Naiara Viana | Oliva, Marco Antônio | Valente, Vânia Maria Moreira
Fluoride is among the most phytotoxic atmospheric pollutants, commonly linked to the appearance of lesions in susceptible plants around emitting sources. In order to assess the effects of fluoride on leaves of Spondias dulcis Parkinson (Anacardiaceae), plants were examined 78 km (non-polluted area) and 0.78 km (polluted area) from an aluminium smelter. The level of fluoride increased with the exposure time of the plants in the polluted area. On the third day of exposure in the polluted area, necroses with typical colouration were observed. Micromorphological damage began at the abaxial epidermis, mainly associated with the stomata. Starch grain accumulation was more pronounced in the midrib. The cell membranes and chloroplasts were greatly affected by the pollutant. We observed accumulation of phenolic compounds and electron-dense material at the boundaries of the ending veinlets. The microscopic events described precede the appearance of symptoms and are therefore of prognostic value in predicting injury by fluoride and will be useful as biomarkers. The high sensitivity of S. dulcis to fluoride and the specificity of the symptoms confirm, for the first time, in an experiment of active biomonitoring, the potential of this species as a bioindicator.
Show more [+] Less [-]Assessment of the Cytogenetic Damage Induced by Chromium Short-Term Exposure in Root Tip Meristems of Barley Seedlings Full text
2014
Truţa, Elena | Mihai, Cosmin | Gherghel, Daniela | Vochita, Gabriela
Heavy metals are determinant factors in increasing environmental pollution, and chromium is considered to be of highest concern because of its genotoxicity in microorganisms, animals, and humans. Relatively few studies are focused on the injury induced in plant genetic material. Therefore, the main objective of this work was to evaluate the extent of the cytogenetic damage induced in root meristems of barley (Hordeum vulgare L.) after short-term seed exposure to 10, 100, 250, and 500 μM K₂Cr₂O₇(Cr(VI) concentration is 1.04, 10.39, 25.99, and 51.99 μg ml⁻¹) and 10, 100, 250, and 500 μM CrCl₃(Cr(III) concentration is 0.52, 5.19, 12.99, and 25.99 μg ml⁻¹). Chromium genotoxic potential was proved by significant increases in the rates of the ana-telophase chromosomal aberrations (1.3–2.3 times higher for K₂Cr₂O₇and 1.7–2.2 times higher for CrCl₃, as compared to the control; p < 0.05, p < 0.01) and of metaphase disturbances (5.0–7.5 times more numerous in chromium-treated groups than in control; p < 0.001). The pattern of the chromosomal aberrations is constituted by chromatid bridges, complex aberrations, lagging, and vagrant chromosomes, while the abnormal metaphases are c-like metaphases, sticky metaphases, and metaphases with chromosomes expulsed from equatorial plate. The mitotic indices and the growth of the barley plantlets in the early ontogeny were stimulated by chromium. The changes induced in the frequency of division stages mainly consisted in prophase and telophase accumulation and diminution of metaphase and anaphase proportion.
Show more [+] Less [-]A Strategy for Monitoring Nitrogen Dioxide Concentrations for Testing Compliance with Health Standards in Streets of a Middle Large City in South East Asia Full text
2014
Heeres, P. | Rineksa, S.
A simple strategy and method is presented to monitor NO₂ health standards in busy streets of middle large South East Asian cities.
Show more [+] Less [-]A New Dispersive Liquid–Liquid Microextraction Method for the Preconcentration of Copper Using 4-Phenyl-3-Thiosemicarbazide and FAAS Detection Full text
2014
The aim of this study is to develop a new method for the preconcentration of copper via a dispersive liquid–liquid microextraction method using 4-phenyl-3-thiosemicarbazide as a ligand and determination with FAAS in different sample types such as plants, soils and natural waters such as seawater. Optimum experimental conditions were determined, and the applicability of the proposed dispersive liquid–liquid microextraction method was investigated. In the first step of the work, the parameters that affect complex formation and extraction, such as volume of extractant/disperser solvent, pH and concentration of the chelating agent, NaCl and surfactant, were optimised. The interference effects from potential concomitants on the determination of the Cu(II) ion were investigated in synthetic mixtures that contain high levels of these ions. These results showed the analytical applicability of the proposed method in different kinds of samples. Under the optimal conditions, the calibration curve was linear over the range 2–600 μg L⁻¹of copper, and the detection limit was 0.69 μg L⁻¹in the original solution (3 Sb/m). The accuracy of the developed method was checked by analysing certified reference materials (QCS-19 (high purity standard), LGC 6156 (harbour sediment) and NBS 1572 (citrus leaves)). Results obtained were in agreement with certified values with a t test showing that no significant differences at the 95 % confidence interval levels were found. The proposed method was applied to seawater, river water, and plant and soil samples. The recovery values for spiked water samples were between 99.7 and 117.3 %.
Show more [+] Less [-]Effect of Coal Combustion Products in Reducing Soluble Phosphorus in Soil II: Leaching Study Full text
2014
Seshadri, Balaji | Bolan, Nanthi S. | Kunhikrishnan, Anitha | Choppala, Girish | Naidu, R.
Phosphorus (P) management in agriculture is crucial for both environmental health and future availability of P resource. Application of P as fertilisers (organic or inorganic) often results in either P accumulation in soil or loss to water bodies, rendering them unavailable to crops. In this study, the mobility of inorganic (KH₂PO₄(PP)) and organic (poultry manure (PM)) P sources, as affected by coal combustion products (CCPs: fly ash (FA) and fluidised bed combustion ash (FBC)) application to soils, was evaluated using column leaching experiments. The incubated samples were also characterised using X-ray diffraction (XRD) and scanning electron microscopy (SEM) to understand their surface properties in relation to P adsorption and leaching. The results showed differential effects of CCPs to P treatments—in the case of PP, the CCPs decreased P leaching by 12.11 % (FA) and 20.56 % (FBC), whereas in the case of PM treatment, both CCPs increased P in leachates by 35.53 % (FA) and 18.44 % (FBC). The decrease in P leaching for PP-treated soil as affected by CCPs was attributed to high pH and Ca concentration. There was a negative relationship between the increase in CCP-induced pH and P leaching demonstrating that pH plays a crucial role in P immobilisation, transformation and leaching. The increase in P leaching for CCP-incubated–PM-treated soils was because of the mineralisation of organic P from PM. The surface chemistry from XRD and SEM results showed an increased surface area for CCPs-incubated soil compared to the control and also showed the presence of Ca-rich minerals in CCPs such as ettringite, wollastonite and merwinite.
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