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Non-steroidal anti-inflammatory drugs in Indian rivers Texte intégral
2014
Shanmugam, Govindaraj | Sampath, Srimurali | Selvaraj, Krishna Kumar | Larsson, D. G Joakim | Ramaswamy, Babu Rajendran
Pharmaceutical concentration data for Indian surface waters are currently scarce. Sewage often enters Indian rivers without prior treatment, and so previously reported environmental concentrations from regions with routinely implemented sewage treatment cannot simply be used to predict concentrations in Indian surface water. Improved knowledge of pharmaceutical concentrations in Indian waters would enable determination of potential risks posed to aquatic wildlife and human health in this region. The concentrations of five common non-steroidal anti-inflammatory drugs (NSAIDs; diclofenac, ketoprofen, naproxen, ibuprofen, and acetylsalicylic acid) were determined in surface waters from 27 locations of the Kaveri, Vellar, and Tamiraparani Rivers in southern India. The samples were extracted by solid-phase extraction and analyzed by GC-MS. The measured concentrations of four of the five drugs in this reconnaissance were relatively similar to those reported elsewhere (ND–200 ng/l); however, acetylsalicylic acid, the most readily degradable of the investigated drugs, was found at all sites and at considerably higher concentrations (up to 660 ng/l) than reported in European surface waters. This is the first report on the occurrence of NSAIDs in Indian rivers. The finding of elevated concentrations of acetylsalicylic acid is most likely a result of direct discharges of untreated sewage. Therefore, readily degradable pharmaceuticals may present larger concern in regions without consistent sewage treatment. Based on measured environmental concentrations, the risks of direct toxicity to aquatic wildlife and of humans consuming the water are discussed.
Afficher plus [+] Moins [-]NAPL migration and ecotoxicity of conventional and renewable fuels in accidental spill scenarios Texte intégral
2014
Malk, Vuokko | Barreto Tejera, Eduardo | Simpanen, Suvi | Dahl, Mari | Mäkelä, Riikka | Häkkinen, Jani | Kiiski, Anna | Penttinen, Olli-Pekka
Fuels derived from non-petroleum renewable resources have raised interest due to their potential in replacing petroleum-based fuels, but information on their fate and effects in the terrestrial and aquatic environments in accidental spill scenario is limited. In this study, migration of four fuels (conventional diesel, conventional gasoline, renewable diesel NExBTL, and ethanol-blended gasoline RE85 containing maximum 85 % ethanol) as non-aqueous phase liquids (NAPL) in soil was demonstrated in a laboratory-scale experiment. Ecotoxicity data was produced for the same fuels. There was no significant difference in migration of conventional and renewable diesel, but gasoline migrated 1.5 times deeper and 7–9 times faster in sand than diesel. RE85 spread horizontally wider but not as deep (p < 0.05) as conventional gasoline. Conventional gasoline was the most toxic (lethal concentration [LC50] 20 mg/kg total hydrocarbon content [THC]) among the studied fuels in soil toxicity test with earthworm Eisenia fetida followed by ethanol-blended gasoline (LC50 1,643 mg/kg THC) and conventional diesel (LC50 2,432 mg/kg THC), although gasoline evaporated fast from soil. For comparison, the toxicity of the water-accommodated fractions (WAF) of the fuels was tested with water flea Daphnia magna and Vibrio fischeri, also demonstrating groundwater toxicity. The WAF of conventional gasoline and RE85 showed almost similar toxicity to both the aquatic test species. EC50 values of 1:10 (by volume) WAF were 9.9 %WAF (gasoline) and 9.3 %WAF (RE85) to D. magna and 9.3 %WAF (gasoline) and 12.3 %WAF (RE85) to V. fischeri. Low solubility decreased toxicity potential of conventional diesel in aquatic environment, but direct physical effects of oil phase pose a threat to organisms in nature. Renewable diesel NExBTL did not show clear toxicity to any test species.
Afficher plus [+] Moins [-]Electrochemical removal of synthetic textile dyes from aqueous solutions using Ti/Pt anode: role of dye structure Texte intégral
2014
Araújo, Cynthia K. C. | Oliveira, Gustavo R. | Fernandes, Nedja S. | Zanta, Carmem L. P. S. | Castro, Suely Souza Leal | da Silva, Djalma R. | Martínez-Huitle, Carlos A.
In this work, the efficiency of electrochemical oxidation (EO) was investigated for removing a dye mixture containing Novacron Yellow (NY) and Remazol Red (RR) in aqueous solutions using platinum supported on titanium (Ti/Pt) as anode. Different current densities (20, 40 and 60 mA cm⁻²) and temperatures (25, 40 and 60 °C) were studied during electrochemical treatment. After that, the EO of each of these dyes was separately investigated. The EO of each of these dyes was performed, varying only the current density and keeping the same temperature (25 °C). The elimination of colour was monitored by UV-visible spectroscopy, and the degradation of organic compounds was analysed by means of chemical oxygen demand (COD). Data obtained from the analysis of the dye mixture showed that the EO process was effective in colour removal, in which more than 90 % was removed. In the case of COD removal, the application of a current density greater than 40 mA cm⁻²favoured the oxygen evolution reaction, and no complete oxidation was achieved. Regarding the analysis of individual anodic oxidation dyes, it was appreciated that the data for the NY were very close to the results obtained for the oxidation of the dye mixture while the RR dye achieved higher colour removal but lower COD elimination. These results suggest that the oxidation efficiency is dependent on the nature of the organic molecule, and it was confirmed by the intermediates identified.
Afficher plus [+] Moins [-]Low-cost adsorbent prepared from sewage sludge and corn stalk for the removal of COD in leachate Texte intégral
2014
He, Ying | Liao, Xiaofeng | Liao, Li | Shu, Wei
Sewage sludge (SS) with corn stalk (CS) was used to prepare SS-based activated carbon (SAC) by pyrolysis with ZnCl₂. The effects of mixing ratio on surface area and pore size distribution, elemental composition, surface chemistry, and morphology were investigated. The results demonstrated that the addition of CS into SS samples improved the surface area (from 92 to 902 m²/g) and the microporosity (from 1.2 to 4.1 %) of the adsorbents and, therefore, enhancing the adsorption performance. The removal of leachate chemical oxygen demand (COD) was also determined. It was found that the COD removal rate reached 85 % at pH 4 with the SAC (90 wt% CS) dosage of 2 % (g/mL) and an adsorption time of 40 min. The adsorption experimental data were fitted by both Langmuir and Freundlich adsorption isotherms. Long-chain alkanes and refractory organics were found in raw leachate, but could be removed by SAC largely.
Afficher plus [+] Moins [-]Concentrations, atmospheric partitioning, and air–water/soil surface exchange of polychlorinated dibenzo-p-dioxin and dibenzofuran along the upper reaches of the Haihe River basin, North China Texte intégral
2014
Nie, Zhiqiang | Die, Qingqi | Yang, Yufei | Tang, Zhenwu | Wang, Qi | Huang, Qifei
Polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) were overall measured and compared in ambient air, water, soils, and sediments along the upper reaches of the Haihe River of North China, so as to evaluate their concentrations, profiles, and to understand the processes of gas–particle partitioning and air–water/soil exchange. The following results were obtained: (1) The average concentrations (toxic equivalents, TEQs) of 2,3,7,8-PCDD/PCDF in air, water, sediment, and soil samples were 4,855 fg/m³, 9.5 pg/L, 99.2 pg/g dry weight (dw), and 56.4 pg/g (203 fg TEQ/m³, 0.46 pg TEQ/L, 2.2 pg TEQ/g dw, and 1.3 pg TEQ/g, respectively), respectively. (2) Although OCDF, 1,2,3,4,6,7,8-HpCDF, OCDD, and 1,2,3,4,6,7,8-HpCDD were the dominant congeners among four environmental sinks, obvious discrepancies of these congener and homologue patterns of PCDD/PCDF were observed still. (3) Significant linear correlations for PCDD/PCDF were observed between the gas–particle partition coefficient (Kₚ) and the subcooled liquid vapor pressure (PL⁰) and octanol–air partition coefficient (Kₒₐ). (4) Fugacity fraction values of air–water exchange indicated that most of PCDD/PCDF homologues were dominated by net volatilization from water into air. The low-chlorinated PCDD/PCDF (tetra- to hexa-) presented a strong net volatilization from the soil into air, while high-chlorinated PCDD/PCDF (hepta- to octa-) were mainly close to equilibrium for air–soil exchange.
Afficher plus [+] Moins [-]Sensitivity of hypogean and epigean freshwater copepods to agricultural pollutants Texte intégral
2014
Di Lorenzo, T. | Di Marzio, W. D. | Sáenz, M. E. | Baratti, M. | Dedonno, A. A. | Iannucci, A. | Cannicci, S. | Messana, G. | Galassi, D. M. P.
Widespread pollution from agriculture is one of the major causes of the poor freshwater quality currently observed across Europe. Several studies have addressed the direct impact of agricultural pollutants on freshwater biota by means of laboratory bioassays; however, as far as copepod crustaceans are concerned, the ecotoxicological research is scarce for freshwater species and almost nonexistent for the hypogean ones. In this study, we conducted a comparative analysis of the available literature data on the sensitivity of freshwater copepods to agricultural pollutants. We also assessed the acute and chronic sensitivity of a hypogean and an epigean species, both belonging to the Crustacea Copepoda Cyclopoida Cyclopidae, to two N-fertilizers (urea and ammonium nitrate) and two herbicides (ARIANEᵀᴹII from Dow AgroSciences LLC, and Imazamox), widely used for cereal agriculture in Europe. According to the literature review, freshwater copepods are sensitive to a range of pesticides and N-fertilizers. Ecotoxicological studies on hypogean species of copepods account only one study. There are no standardized protocols available for acute and chronic toxicity tests for freshwater copepods, making comparisons about sensitivity difficult. From our experiments, ionized ammonia proved to be more toxic than the herbicide Imazamox, in both short and chronic bioassays. Urea was the less toxic chemical for both species. The hypogean species was more sensitive than the epigean one to all chemicals. For both species and for all tested chemicals, acute lethality and chronic lethality were induced at concentrations higher than the law limits of good water body quality in Europe, except for ionized ammonia, which provoked the chronic lethality of the hypogean species at a lower concentration. The hazardous concentration (HC) of un-ionized ammonia for 5 % of freshwater copepods, obtained by a species sensitivity distribution, was 92 μg l⁻¹, significantly lower than the HC computed for traditional test species from freshwater environments.
Afficher plus [+] Moins [-]High throughput and miniaturised systems for biodegradability assessments Texte intégral
2014
Cregut, Mickael | Jouanneau, Sulivan | Brillet, François | Durand, Marie-José | Sweetlove, Cyril | Chenèble, Jean-Charles | L’Haridon, Jacques | Thouand, Gérald
The society demands safer products with a better ecological profile. Regulatory criteria have been developed to prevent risks for human health and the environment, for example, within the framework of the European regulation REACH (Regulation (EC) No 1907, 2006). This has driven industry to consider the development of high throughput screening methodologies for assessing chemical biodegradability. These new screening methodologies must be scalable for miniaturisation, reproducible and as reliable as existing procedures for enhanced biodegradability assessment. Here, we evaluate two alternative systems that can be scaled for high throughput screening and conveniently miniaturised to limit costs in comparison with traditional testing. These systems are based on two dyes as follows: an invasive fluorescent dyes that serves as a cellular activity marker (a resazurin-like dye reagent) and a noninvasive fluorescent oxygen optosensor dye (an optical sensor). The advantages and limitations of these platforms for biodegradability assessment are presented. Our results confirm the feasibility of these systems for evaluating and screening chemicals for ready biodegradability. The optosensor is a miniaturised version of a component already used in traditional ready biodegradability testing, whereas the resazurin dye offers an interesting new screening mechanism for chemical concentrations greater than 10 mg/l that are not amenable to traditional closed bottle tests. The use of these approaches allows generalisation of high throughput screening methodologies to meet the need of developing new compounds with a favourable ecological profile and also assessment for regulatory purpose.
Afficher plus [+] Moins [-]Biodegradation potential of cyano-based ionic liquid anions in a culture of Cupriavidus spp. and their in vitro enzymatic hydrolysis by nitrile hydratase Texte intégral
2014
Neumann, Jennifer | Pawlik, Magdalena | Bryniok, Dieter | Thöming, Jorg | Stolte, Stefan
Biodegradation tests with bacteria from activated sludge revealed the probable persistence of cyano-based ionic liquid anions when these leave waste water treatment plants. A possible biological treatment using bacteria capable of biodegrading similar compounds, namely cyanide and cyano-complexes, was therefore examined. With these bacteria from the genera Cupriavidus, the ionic liquid anions B(CN)₄⁻, C(CN)₃⁻, N(CN)₂⁻combined with alkaline cations were tested in different growth media using ion chromatography for the examination of their primary biodegradability. However, no enhanced biodegradability of the tested cyano-based ionic liquids was observed. Therefore, an in vitro enzymatic hydrolysis test was additionally run showing that all tested ionic liquid (IL) anions can be hydrolysed to their corresponding amides by nitrile hydratase, but not by nitrilase under the experimental conditions. The biological stability of the cyano-based anions is an advantage in technological application, but the occurrence of enzymes that are able to hydrolyse the parent compound gives a new perspective on future cyano-based IL anion treatment.
Afficher plus [+] Moins [-]Phytomanagement of Cd-contaminated soils using maize (Zea mays L.) assisted by plant growth-promoting rhizobacteria Texte intégral
2014
Moreira, Helena | Marques, Ana P. G. C. | Franco, Albina R. | Rangel, António O. S. S. | Castro, Paula M. L.
Zea mays (L.) is a crop widely cultivated throughout the world and can be considered suitable for phytomanagement due to its metal resistance and energetic value. In this study, the effect of two plant growth-promoting rhizobacteria, Ralstonia eutropha and Chryseobacterium humi, on growth and metal uptake of Z. mays plants in soils contaminated with up to 30 mg Cd kg⁻¹was evaluated. Bacterial inoculation increased plant biomass up to 63 % and led to a decrease of up to 81 % in Cd shoot levels (4–88 mg Cd kg⁻¹) and to an increase of up to 186 % in accumulation in the roots (52–134 mg Cd kg⁻¹). The rhizosphere community structure changed throughout the experiment and varied with different levels of Cd soil contamination, as revealed by molecular biology techniques. Z. mays plants inoculated with either of the tested strains may have potential application in a strategy of soil remediation, in particular short-term phytostabilization, coupled with biomass production for energy purposes.
Afficher plus [+] Moins [-]Severe particulate pollution from the deposition practices of the primary materials of a cement plant Texte intégral
2014
Kourtidis, K. | Rapsomanikis, S. | Zerefos, C. | Georgoulias, A. K. | Pavlidou, E.
Global cement production has increased twofold during the last decade. This increase has been accompanied by the installation of many new plants, especially in Southeast Asia. Although various aspects of pollution related to cement production have been reported, the impact of primary material deposition practices on ambient air quality has not yet been studied. In this study, we show that deposition practices can have a very serious impact on levels of ambient aerosols, far larger than other cement production-related impacts. Analyses of ambient particulates sampled near a cement plant show 1.3–30.4 mg/m³total suspended particulates in the air and concentrations of particles with a diameter of 10 μm or less at 0.04–3 mg/m³. These concentrations are very high and seriously exceed air quality standards. We unequivocally attribute these levels to outdoor deposition of cement primary materials, especially clinker, using scanning electron microscopy/energy-dispersive X-ray spectroscopy. We also used satellite-derived aerosol optical depth maps over the area of study to estimate the extent of the spatial impact. The satellite data indicate a 33 % decrease in aerosol optical depth during a 10-year period, possibly due to changing primary material deposition practices. Although the in situ sampling was performed in one location, primary materials used in cement production are common in all parts of the world and have not changed significantly over the last decades. Hence, the results reported here demonstrate the dominant impact of deposition practices on aerosol levels near cement plants.
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