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Photocatalytic Degradation of Ibuprofen Using TiO2 and Ecotoxicological Assessment of Degradation Intermediates against Daphnia similis  [PDF]
Farley S. Braz, Milady R. A. Silva, Flávio S. Silva, Sandro J. Andrade, Ana L. Fonseca, Márcia M. Kondo
Journal of Environmental Protection (JEP) , 2014, DOI: 10.4236/jep.2014.57063
Abstract:

Several pharmaceutical compounds have been detected in natural aqueous systems and ibuprofen (IBF), one of the most consumed medicament, has been detected in many countries. The degradation efficiency of IBF under TiO2/UV radiation was evaluated. Optimum degradation results were observed using 20 mg·L-1 of TiO2, pH 7.8 and 5 mg·L-1 of IBF. Under these experimental conditions total IBF removal was achieved in less than 60 min of irradiation. Although total IBF concentration was observed, the total mineralization of the compound was not achieved. The by-products generated during TiO2/UV reaction showed to be more toxic against Daphnia similis than the initial IBF present in aqueous solution.

Limnological and ecotoxicological studies in the cascade of reservoirs in the Tietê river (S?o Paulo, Brazil)
Rodgher, S.;Espíndola, E. L. G.;Rocha, O.;Fracácio, R.;Pereira, R. H. G.;Rodrigues, M. H. S.;
Brazilian Journal of Biology , 2005, DOI: 10.1590/S1519-69842005000400017
Abstract: an evaluation was made of the quality of samples of water and sediment collected from a series of reservoirs in the tietê river (sp), based on limnological and ecotoxicological analyses. the samples were collected during two periods (feb and jul 2000) from 15 sampling stations. acute toxicity bioassays were performed using the test organism daphnia similis, while chronic bioassays were carried out withceriodaphnia dubia and danio rerio larvae. the water samples were analyzed for total nutrients, total suspended matter and total cadmium, chromium, copper and zinc concentrations, while the sediment samples were examined for organic matter, granulometry and potentially bioavailable metals (cadmium, chromium, copper and zinc). the results obtained for the limnological variable, revealed differences in the water quality, with high contribution of nutrients and metals for tietê and piracicaba rivers, besides the incorporation and sedimentation, consequently causing a reduction of materials in barra bonita reservoir, thus promoting the improvement of the water quality in the other reservoirs. the toxicity bioassays revealed acute toxicity for daphnia similis only in the reservoirs located below barra bonita dam. on the other hand, chronic toxicity for ceriodaphnia dubia and acute for danio rerio showed a different pattern, decreasing in magnitude from barra bonita to três irm?os, demonstrating an environmental degradation gradient in the reservoirs.
Chemical constituents and ecotoxicological effects of leaf extracts Eucalyptus urograndis
Lucienir Pains Duarte, Rute Cunha Figueiredo, Débora Barbosa da Silva Soares, Marcela Maciel Nogueira,Fabíola Oliveira Lino de Araújo, Arnola Cecília Rietzler
Exatas Online , 2010,
Abstract: Artificial forests of Eucalyptus produce large amounts of litterbag that by the action of wind andrainwater are dragged into aquatic environment, with consequent alteration of the aquatic ecosystems.For evaluate the ecotoxicological effect of Eucalyptus urograndis litterbag in the aquatic environment;there were prepared organic extracts (hexane, chloroform, ethyl acetate and ethanol), besides anaqueous extract. These polar extracts were tested in vitro against Daphnia similis and D. laevis(Anomopoda: Daphiniidae) as the biological indicators while Chironomus xanthus (Diptera:Chironomidae) was used as bio-indicators for the less polar ones. The testing confirmed the presence oftoxic activity in all extracts and indicated the ecotoxicological potential of the E. urograndis leaves inaquatic environments. The test results pointed to the need of new sustainable technologies allow thepreservation of aquatic environments located in the vicinity of Eucalyptus sp. fields. Concomitantly tothe ecotoxicological studies, hexane and chloroform extracts of litterbag leaves were subjected tophytochemical study, leading to the isolation of 5-hydroxy-4’,7-dimethoxy-6,8-dimethylflavone(eucalyptin), 2-(4 -hydroxyphenyl)ethyl nonacosanoate and long chain alcohol. These two extracts,along with the aqueous extract were derivatized with BSTFA and then analyzed by GC-MS, allowingto detect 25 organic compounds, mainly fatty acids, long chain hydrocarbons, steroids, carbohydratesand long chain alcohols.
Influence of RANEY Nickel on the Formation of Intermediates in the Degradation of Lignin  [PDF]
Daniel Forchheim,Ursel Hornung,Philipp Kempe,Andrea Kruse,David Steinbach
International Journal of Chemical Engineering , 2012, DOI: 10.1155/2012/589749
Abstract: Lignin forms an important part of lignocellulosic biomass and is an abundantly available residue. It is a potential renewable source of phenol. Liquefaction of enzymatic hydrolysis lignin as well as catalytical hydrodeoxygenation of the main intermediates in the degradation of lignin, that is, catechol and guaiacol, was studied. The cleavage of the ether bonds, which are abundant in the molecular structure of lignin, can be realised in near-critical water (573 to 673?K, 20 to 30?MPa). Hydrothermal treatment in this context provides high selectivity in respect to hydroxybenzenes, especially catechol. RANEY Nickel was found to be an adequate catalyst for hydrodeoxygenation. Although it does not influence the cleavage of ether bonds, RANEY Nickel favours the production of phenol from both lignin and catechol. The main product from hydrodeoxygenation of guaiacol with RANEY Nickel was cyclohexanol. Reaction mechanism and kinetics of the degradation of guaiacol were explored. 1. Introduction Earth?s resources of crude oil are limited [1]. An important challenge for scientists and engineers is to develop technologies that are largely independent from fossil crude oils. Biomass, especially organic waste material, has a high potential to replace crude oil as a basic input material for the production of many organic chemicals. Lignocellulosic biomass is one of the most abundant renewable organic materials in the world. Lignin, a major component of lignocellulosic biomass, is mostly available as waste material. The paper industry produces more than 50 million tons of dry lignin every year worldwide [2]. It is mainly burned to recover its energetic value. Lignin has a structure similar to brown coal, being an aromatic heteropolymer. The three basic building blocks, p-coumaryl alcohol, coniferyl alcohol, and sinapyl alcohol. are interlinked by C–C or ether bonds. The latter is the weaker one of the two bonds mentioned and thus of high interest for lignin degradation. As lignin is relatively resistant to chemical or enzymatic degradation, harsh reaction conditions are required to break down this polymer [3]. By cleavage of the ether bonds, aromatic monomers are formed. Thus lignin provides high potential to serve as a renewable source for phenol or benzene [4]. Phenol is extremely interesting as building block for synthetic polymers, resins, and epoxy- or polyurethane [3]. It is however a challenge to gain a high-value product from a chemically complicated and inhomogeneous component as lignin. In order to do so, char formation is to be avoided. Char formation can be
Ecotoxicological evaluation of leachate from the Limeira sanitary landfill with a view to identifying acute toxicity  [cached]
Núbia Natália de Brito Pelegrini,Ronaldo Teixeira Pelegrini,José Euclides Stipp Paterniani
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2007,
Abstract: Final disposal of solid waste is still a cause for serious impacts on the environment. In sanitary landfills, waste undergoes physical, chemical, and biological decomposition, generating biogas and leachate. Leachate is a highly toxic liquid with a very high pollution potential. The purpose of this work is to evaluate toxicity of in natura leachate samples collected from Limeira Sanitary Landfill, in Limeira, SP. The ecotoxicological evaluation comprised acute toxicity assays using as test organisms Daphnia Similis, seeds of Eruca sativa (arugula), and Allium cepa roots (onion). Analyses of color, pH, turbidity, conductivity, hardness, nitrogen, total organic carbon (TOC), adsorbable organic halogen (AOX), and metals were also carried out. The main results for Eruca sativa (arugula) and Allium cepa (onion) indicated that the diluted leachate 50% presented similar toxicity to the phenol solution of 1000 mg.L-1 for arugula and 2000 mg.L-1 for onion. With the solution of Cr+6 concentrations of 3000 mg.L-1 for arugula and 2000 mg.L-1 for onion were found. For analyses with Daphnia Similis the EC50 was 9.3% on average. This way it was possible to observe that biological tests are necessary to evaluate the pollution in the effluents or water bodies. These tests serve to determine the toxic potential of a chemical agent or complex mixture.
Recent advances in microbial degradation of ibuprofen - A review
布洛芬微生物降解研究进展

Yahong Wei,Jie Liu,Dong Qu,
卫亚红
,刘杰,曲东

微生物学报 , 2011,
Abstract: Abstract: Ibuprofen has been recognized as an environmental endocrine disruptor due to its ability to interfere with prostaglandin synthesis. In order to address the myriad challenges faced by the issue of ibuprofen in the environment, the recent research progress was summarized in this paper to characterize the ibuprofen consumption, its potential hazard, and biodegradation and degradation mechanisms. The importance and urgency to carry out the ibuprofen degradable gene cloning, its function analysis and its molecular degradation mechanisms were emphasized.
Electrochemical detection and degradation of ibuprofen from water on multi-walled carbon nanotubes-epoxy composite electrode
Sorina Moto,Adriana Remes,Aniela Pop,Florica Manea,Joop Schoonman,
Sorina Moto
,Adriana Remes,Aniela Pop,Florica Mane,Joop Schoonman

环境科学学报(英文版) , 2013,
Abstract: This work describes the electrochemical behaviour of ibuprofen on two types of multi-walled carbon nanotubes based composite electrodes, i.e., multi-walled carbon nanotubes-epoxy (MWCNT) and silver-modified zeolite-multi-walled carbon nanotubes-epoxy (AgZMWCNT) composites electrodes. The composite electrodes were obtained using two-roll mill procedure. SEM images of surfaces of the composites revealed a homogeneous distribution of the composite components within the epoxy matrix. AgZMWCNT composite electrode exhibited the better electrical conductivity and larger electroactive surface area. The electrochemical determination of ibuprofen (IBP) was achieved using AgZMWCNT by cyclic voltammetry, differential-pulsed voltammetry, square-wave voltammetry and chronoamperometry. The IBP degradation occurred on both composite electrodes under controlled electrolysis at 1.2 and 1.75 V vs. Ag/AgCl, and IBP concentration was determined comparatively by differential-pulsed voltammetry, under optimized conditions using AgZMWCNT electrode and UV-Vis spectrophotometry methods to determine the IBP degradation performance for each electrode. AgZMWCNT electrode exhibited a dual character allowing a double application in IBP degradation process and its control.
Evaluation of Acute Chromium (III) Toxicity in Relation to Daphnia Similis  [PDF]
Petr Melnikov, Tania C. M. de Freitas
Journal of Water Resource and Protection (JWARP) , 2011, DOI: 10.4236/jwarp.2011.32015
Abstract: Acute chromium (III) toxicity in relation to Daphnia similis, most appropriate for Brazilian environment has been evaluated. The preliminary toxicity test showed that the median effective concentration was 10 mg/l. After having performed the final test, the immobility percentage was calculated for each concentration in relation to the total number of the used organisms within the chosen pH range. It was shown that the proposed methodology rendered realistic results and the 48-h CE50 value under the test conditions is 3.24 mg/l. The minimum concentration that did not show any toxicity to Daphnia similis was 2.5 mg of chromium (III) per liter. The obtained level is superior to the maximum limit recommended by the Brazilian norms, 0.5 mg/l.
Chlorobenzene degradation by electro-heterogeneous catalysis in aqueous solution: intermediates and reaction mechanism

WANG Jiade,MEI Yu,LIU Chenliang,CHEN Jianmeng,

环境科学学报(英文版) , 2008,
Abstract: This study was performed to investigate the variables that influence chlorobenzene (CB) degradation in aqueous solution by electro-heterogeneous catalysis. The effects of current density, pH, and electrolyte concentration on CB degradation were determined. The degradation efficiency of CB was almost 100% with an initial CB concentration of 50 mg/L, current density 15 mA/cm2, initial pH 10, electrolyte concentration 0.1 mol/L, and temperature 25℃ after 90 min of reaction. Under the same conditions, the degradation efficiency of CB was only 51% by electrochemical (EC) process, which showed that electro-heterogeneous catalysis was more efficient than EC alone. The analysis results of Purge-and-Trap chromatography-mass spectrometry (P&T/GC/MS) and ion chromatography the release of Cl-. Further oxidation of phenol and biphenyl produced p-Vinylbenzoic acid and hydroquinol. Finally, the compounds were oxidized to butenedioic acid and other small-molecule acids.
Adsorption and Photocatalytic Decomposition of the -Blocker Metoprolol in Aqueous Titanium Dioxide Suspensions: Kinetics, Intermediates, and Degradation Pathways  [PDF]
Violette Romero,Pilar Marco,Jaime Giménez,Santiago Esplugas
International Journal of Photoenergy , 2013, DOI: 10.1155/2013/138918
Abstract: This study reports the photocatalytic degradation of the -blocker metoprolol (MET) using TiO2 suspended as catalyst. A series of photoexperiments were carried out by a UV lamp, emitting in the 250–400?nm range, providing information about the absorption of radiation in the photoreactor wall. The influence of the radiation wavelength on the MET photooxidation rate was investigated using a filter cutting out wavelengths shorter than 280?nm. Effects of photolysis and adsorption at different initial pH were studied to evaluate noncatalytic degradation for this pharmaceutical. MET adsorption onto titania was fitted to two-parameter Langmuir isotherm. From adsorption results it appears that the photocatalytic degradation can occur mainly on the surface of TiO2. MET removed by photocatalysis was 100% conditions within 300?min, while only 26% was achieved by photolysis at the same time. TiO2 photocatalysis degradation of MET in the first stage of the reaction followed approximately a pseudo-first-order model. The major reaction intermediates were identified by LC/MS analysis such as 3-(propan-2-ylamino)propane-1,2-diol or 3-aminoprop-1-en-2-ol. Based on the identified intermediates, a photocatalytic degradation pathway was proposed, including the cleavage of side chain and the hydroxylation addition to the parent compounds. 1. Introduction The presence of pharmaceutical drugs and endocrine disruptors in surface, ground, and drinking waters is a growing environmental concern [1–9]. This pollution is caused by emission from production sites, direct disposal of surplus drugs in households, excretion after drug administration to humans and animals, wastewater from fish and other animal farms, and industry [3, 10, 11]. Some of these drugs, as -blockers, have been detected in the order of ng?L?1 to g?L?1 in the water [3–9, 12]. As an example, metoprolol tartrate salt (MET), which is usually prescribed as antihypertensive or antiarrhythmic, has been quantified up to 2? g?L?1 in sewage treatment plant (STP) effluents and to 240?ng?L?1 in rivers [13]. Metoprolol and atenolol together account for more than 80% of total -blockers consumption in Europe [6]. During the last years, metoprolol usage increased by a factor of 4, probably due to a change in human behavior [6]. Although full ecotoxicity data are not available [13, 14], it has been shown that they can adversely affect aquatic organisms, even at low concentration [2]. Due to its widespread occurrence and potential impact, MET must be removed from treated water before discharge or reuse. Several treatments for the
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