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1.
Water Sci Technol ; 88(10): 2677-2693, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38017685

RESUMEN

Vinasse, due to its high organic load, low pH, high corrosivity, and high potassium levels, can cause salinization, acidification, loss of fertility, and leaching of constituents when applied to agricultural soils. In this context, electrodialysis (ED) was used to remove potassium from this effluent, to concentrate it in the cathode concentrate compartment. The cathode concentrate was subjected to nanofiltration (NF), allowing the electrolyte to be reconditioned and simultaneously generating a solution rich in potassium, making it an input for the fertilizer industry. The conditions of NF were optimized by the design of experiments. The optimal conditions obtained were 6 bar pressure, 1.8 L min-1 flow, and 1.6× feed dilution factor. Although the reconditioned electrolyte has been feasible, the raw vinasse (pre-ultrafiltered) was compared and proved to be a sustainable option. The NF permeate had a potassium concentration of 90% and magnesium of 84%, in addition to the annual reduction in magnesium sulfate demand (139,450,988 kg) and distilled water (5,019 m3). It was also possible to obtain an increase of approximately 400% in the rate of the application of vinasse in fertigation without compromising the needs of the plantation, the quality of the soil, and groundwater.


Asunto(s)
Agricultura , Suelo , Potasio , Electrólitos
2.
Waste Manag Res ; 41(11): 1674-1683, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37265168

RESUMEN

The management of solid waste is one of the biggest challenges for sustainability. Aiming at gains of scale, guaranteeing universal access and the technical and economic viability of the services, intermunicipal cooperation has been implemented in several countries, and in Brazil, it presents itself as one of the main instruments of public policies in the sector of sanitation. The main objective of this article is to propose a set of indicators and the construction of an index to evaluate the performance of regionalized management of urban solid waste, applying them to intermunicipal public consortia operating in Brazil. Based on the Delphi methodology, a total of 15 indicators were defined, divided into 5 sustainability dimensions, used for the construction of the Regionalized Urban Solid Waste Management Performance Index (IDGRSU). In Brazil, the performance of regionalized management was classified as Regular for most of the operating consortia analysed. The adequacy of the final disposal in regional sanitary landfills is the common practice among the municipalities, and consequently, the reduction of the areas of dumps represents the main advance in the management. The index developed proved to be an important instrument to support municipalities and consortia for waste management, contributing to the implementation of sustainable strategies and to the development of policies, and its application in other countries is feasible, regardless of the size of the municipalities.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Residuos Sólidos , Instalaciones de Eliminación de Residuos , Brasil , Ciudades
3.
J Oral Pathol Med ; 51(7): 666-673, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35706152

RESUMEN

BACKGROUND: Giant cell granuloma of the jaws are benign osteolytic lesions of the jaws. These lesions are genetically characterized by mutually exclusive somatic mutations at TRPV4, KRAS, and FGFR1, and a fourth molecular subgroup which is wild-type for the three mutations. Irrespective of the molecular background, giant cell granulomas show MAPK/ERK activation. However, it remains unclear if these mutations lead to differences in their molecular signaling in giant cell granulomas. METHODS: Metabolomics, proteomics, and phosphoproteomics analyses were carried out in formalin-fixed paraffin-embedded samples of giant cell granuloma of the jaws. The study cohort consisted of five lesions harboring mutations in FGFR1, six in KRAS, five in TRPV4, and five that were wild-type for these mutations. RESULTS: Lesions harboring KRAS or FGFR1 mutations showed overall similar proteomics and metabolomics profiles. In all four groups, metabolic pathways showed similarity in apoptosis, cell signaling, gene expression, cell differentiation, and erythrocyte activity. Lesions harboring TRPV4 mutations showed a greater number of enriched pathways related to tissue architecture. On the other hand, the wild-type group presented increased number of enriched pathways related to protein metabolism compared to the other groups. CONCLUSION: Despite some minor differences, our results revealed an overall similar molecular profile among the groups with different mutational profile at the metabolic, proteic, and phosphopeptidic levels.


Asunto(s)
Granuloma de Células Gigantes , Canales Catiónicos TRPV , Granuloma de Células Gigantes/genética , Granuloma de Células Gigantes/metabolismo , Humanos , Maxilares/metabolismo , Maxilares/patología , Metabolómica , Mutación , Proteómica , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo
4.
Oral Dis ; 28(8): 2219-2229, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33978981

RESUMEN

OBJECTIVE: We aimed to assess which metabolic pathways would be implicated in the phenotypic changes of the epithelial lining of odontogenic keratocyst after marsupialization, comparing pre- and post-marsupialized lesions with adjacent oral mucosa. MATERIALS AND METHODS: Eighteen formalin-fixed and paraffin-embedded tissues from six subjects were divided into three paired groups: odontogenic keratocyst pre- (n = 6) and post-marsupialization (n = 6), and adjacent oral mucosa (n = 6). The metabolic pathways found in these groups were obtained by high-performance liquid chromatography-mass spectrometry-based untargeted metabolomics performed. RESULTS: Through putative metabolite annotation followed by pathway enrichment and predictive analysis with automated algorithms (Mummichog and Gene Set Enrichment Analysis), we found differences in many cellular processes that may be involved in inflammation, oxidative stress response, keratinocyte-basal membrane attachment, differentiation, and proliferation functions, all relevant to odontogenic keratocyst pathobiology and the phenotype acquired after marsupialization. CONCLUSION: Our study was able to identify several metabolic pathways potentially involved in the metaplastic changes induced by marsupialization of odontogenic keratocysts. An improved comprehension of this process could pave the way for the development of targeted therapies.


Asunto(s)
Quistes Odontogénicos , Tumores Odontogénicos , Formaldehído , Humanos , Quistes Odontogénicos/patología , Quistes Odontogénicos/cirugía , Proyectos Piloto
5.
Waste Manag Res ; 40(7): 892-904, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34877898

RESUMEN

This article presents an approach to compensate waste pickers in the informal sector of Minas Gerais state, Brazil, via a Payment for Urban Environmental Services (PUES) instrument, called 'Recycling Exchange'. The aim is to evaluate the effects of this instrument on the amount of waste diverted from landfill and reintroduced into the production chain, and to increase recognition of waste pickers' contributions to the state's economy. It was found that the 'Recycling Exchange' met the fundamental objectives of a PUES: the double social and economic benefits of the social inclusion of waste pickers in the execution of the public policy for solid waste management, and inducing (in the case of glass), ensuring and stabilising (plastic and paper) continuity of the activity of selling recyclables in times of wide price fluctuations for these recyclables. The instrument enhanced the provision of this environmental service and the positive externalities associated with recycling.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Brasil , Reciclaje , Residuos Sólidos/análisis
6.
J Environ Manage ; 288: 112475, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-33823445

RESUMEN

The necessity for landfill leachate treatment is a requisite to reduce the environmental impact related to municipal solid waste landfills and different aspects must be considered while deciding for an appropriate treatment process. For example, it was demonstrated that the landfill leachate stabilization in tropical regions is achieved right after its first year of operation, requiring technologies capable of treating leachates of a higher recalcitrant character if compared to those leachates from temperate regions and same landfill age. In view of its complexity and variability, stand-alone processes (either biological or physicochemical) are often ineffective in attaining the threshold values for its discharge in receiving bodies. Due to that fact, full-scale facilities have adopted integrated routes, harvesting the benefits of both biological and physicochemical processes. The implementation of membrane bioreactors followed by polishing membrane separation process (nanofiltration and reverse osmosis) seems to be a trend in leachate treatment by full-scale treatment plants. This technology is widely employed in China, European countries, and tropical countries as Brazil, generally with a treatment cost lower than the costs related to its disposal in domestic effluent collection systems. From the technologies already employed by full-scale facilities, four integrated routes were proposed for a sensitive analysis considering the treatment of a landfill leachate of different physicochemical characteristics. From all routes, those employing the membrane separation process as a polishing step had a better efficacy in attaining the threshold values for leachate disposal, being that an interesting alternative for leachate polishing by full-scale facilities.


Asunto(s)
Eliminación de Residuos , Contaminantes Químicos del Agua , Brasil , China , Europa (Continente) , Residuos Sólidos/análisis , Instalaciones de Eliminación de Residuos , Contaminantes Químicos del Agua/análisis
7.
Water Sci Technol ; 84(12): 3780-3790, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34928843

RESUMEN

The high resilience to biological treatments from the landfill leachate is generally associated with the presence of humic substances (HS). The brown color characteristic of this effluent is also related to these substances. Landfill leachate with low biodegradability can make biological treatments unfeasible, which can drive up the cost for the treatment of large leachate volumes. In this context, this research aimed to characterize the leachate in different seasonal periods, and verify the influence of HS species on the biodegradability of the effluent to assist in the selection of adequate treatment techniques. The HS quantification was performed using the modified Lowry method and speciation through fractionation according to the molar masses of the HS species. The tropical regions can be the precursor for the rapid stabilization of biodegradable organic matter. The warmer climate contributed to a reduced BOD/COD ratio (0.03) and the predominance of compounds of lower mass (e.g.: fulvic acids). The tests showed an HS concentration of 26.9% of the total COD in the raw leachate in the rainy season, which increased to 37.3% in the dry season. Approximately 70% of HS species refer to fulvic acids, a fraction identified as having the highest biologic treatment resilience.


Asunto(s)
Sustancias Húmicas , Contaminantes Químicos del Agua
8.
Ecotoxicology ; 29(7): 1062-1071, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32588236

RESUMEN

High consumption of drugs, combined with their presence in the environment, raises concerns about its consequences. Even though researches are often engaged in analyzing substances separately, that is not the environmental reality. Therefore, the aim of this study was to investigate the acute toxicity of the pharmaceuticals simvastatin, metformin, omeprazole and diazepam, and all possible mixtures between them, to the organism Aliivibrio fischeri, verifying possible synergistic or antagonistic effects and assessing byproducts formation. In terms of individual toxicity, omeprazole is the most toxic of the active ingredients, followed by simvastatin, diazepam and, finally, metformin. When the toxicity of mixtures was tested, synergism, antagonism and hormesis were perceived, most probably generated due to byproducts formation. Moreover, it was observed that even when compounds are at concentrations below the non-observed effect concentration (NOEC), there may be toxicity to the mixture. Hence, this work points to the urgent need for more studies involving mixtures, since chemicals are subject to interactions and modifications, can mix, and potentiate or nullify the toxic effect of each other.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Diazepam/toxicidad , Metformina/toxicidad , Omeprazol/toxicidad , Simvastatina/toxicidad , Pruebas de Toxicidad Aguda
9.
Waste Manag Res ; 35(12): 1254-1265, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29070007

RESUMEN

The implementation of reverse logistics systems (RLS) for post-consumer products provides environmental and economic benefits, since it increases recycling potential. However, RLS implantation and consolidation still face problems. The main shortcomings are the high costs and the low expectation of broad implementation worldwide. This paper presents two mathematical models to decide the number and the location of screening centers (SCs) and valorization centers (VCs) to implement reverse logistics of post-consumer packages, defining the optimum territorial arrangements (OTAs), allowing the inclusion of small and medium size municipalities. The paper aims to fill a gap in the literature on RLS location facilities that not only aim at revenue optimization, but also the participation of the population, the involvement of pickers and the service universalization. The results showed that implementation of VCs can lead to revenue/cost ratio higher than 100%. The results of this study can supply companies and government agencies with a global view on the parameters that influence RLS sustainability and help them make decisions about the location of these facilities and the best reverse flows with the social inclusion of pickers and serving the population of small and medium-sized municipalities.


Asunto(s)
Embalaje de Productos , Reciclaje , Administración de Residuos , Ciudades , Modelos Teóricos
10.
J Environ Manage ; 154: 8-12, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25700351

RESUMEN

This study aimed to evaluate the degradation of the antibiotic norfloxacin, using direct photolysis (UV), photolysis with hydrogen peroxide (UV/H2O2) and Fenton's oxidation processes. Initially, it was evaluated the behavior of the antibiotic norfloxacin on direct photolysis, in order to see if the process could be a pertinent way to eliminate the drug in water treatment stations. The results showed that the use of direct photolysis was not effective in the degradation of the antibiotic, reaching a degradation rate of 85% and a mineralization rate of 2% in 7 h of reaction; leading to the formation of intermediates products. To optimize the UV treatment, it was used the combined UV/H2O2 process. Several concentrations of hydrogen peroxide (0.7, 1.4, 2.1, 2.8, 3.5 and 4.2 mmol/L) at pH 7 were tested. The concentration of 2.1 mmol/L reached a degradation rate of 100% in 100 min of reaction. Based on this result, the speed of the reaction at pH 2, 3, 5, and 10 was evaluated for that same concentration of H2O2. The shortest reaction time (60 min) was verified at pH 2 and 3. For the treatment using Fenton oxidation, a degradation rate of 60% of the compound and a mineralization rate of 55% was obtained in 60 min. The study revealed that the Fenton oxidation and UV/H2O2 can be used for norfloxacin removal, reaching respectively degradation rates of 100% and 60%, and mineralization rates of 55% and 32%.


Asunto(s)
Antibacterianos/química , Antibacterianos/efectos de la radiación , Restauración y Remediación Ambiental/métodos , Peróxido de Hidrógeno/química , Norfloxacino/química , Fotoquímica , Rayos Ultravioleta , Contaminantes Químicos del Agua/efectos de la radiación , Purificación del Agua/métodos , Hierro , Oxidación-Reducción , Fotólisis
11.
Water Sci Technol ; 70(2): 265-71, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25051473

RESUMEN

The purpose of studying the biodegradability of pharmaceutical compounds is to evaluate their behaviors in relation to the treatment processes generally used in domestic and industrial wastewater treatment plants. The antibiotic norfloxacin was found to be a recalcitrant compound. The studies conducted showed norfloxacin removal rates of 12% and 18% when biomasses from treatments with activated sludge and anaerobic biodigesters, respectively, were used without acclimatization. This suggests that anaerobic digestion shows better performance for norfloxacin removal. Ecotoxicological tests, using the luminescent marine bacteria Aliivibrio fischeri as the test organism, show that anaerobic digestion could eliminate the toxicity of the antibiotic norfloxacin, even though total degradation of the drug was not observed. The release of norfloxacin during cell lysis suggests the importance of controlling this phenomenon in biological treatment systems that handle wastewater contaminated with norfloxacin, thus preventing the return of this drug to the environment.


Asunto(s)
Biodegradación Ambiental , Reactores Biológicos , Norfloxacino/química , Norfloxacino/metabolismo , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Aerobiosis , Anaerobiosis , Antibacterianos/química , Antibacterianos/metabolismo
12.
Water Sci Technol ; 68(7): 1607-13, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24135111

RESUMEN

Chemical precipitation of struvite as a technique of ammonium nitrogen (NH(4)-N) removal from concentrated wastewater has been shown to be an attractive alternative due to its high effectiveness, reaction rate, simplicity, environmental sustainability and, especially, the application potential of the generated solids for the fertilizer industry. The technique of experimental design has been used in order to identify and evaluate the optimum conditions of chemical precipitation reaction applied in a struvite sedimentation study. The preliminary tests were performed using synthetic effluent with a concentration equal to 500.0 mg N L(-1). The stoichiometric ratio Mg:NH(4):PO(4) equal to 1.5:1.0:1.25 and pH equal to 8.5 were taken to be the optimum conditions, where a NH(4)-N removal equal to 98.6% was achieved with only 10-min reaction time. This condition has been used to evaluate the struvite sedimentation from synthetic wastewaters, intending to check the optimum conditions achieved by the experimental design in different initial concentrations, 1,000 and 2,000 mg N L(-1). The results were typical of a good zonal sedimentation and can be used in the scale up the system.


Asunto(s)
Compuestos de Amonio/química , Compuestos de Magnesio/química , Fosfatos/química , Aguas Residuales/química , Precipitación Química , Magnesio , Análisis Multivariante , Estruvita , Purificación del Agua
13.
Leuk Lymphoma ; 64(11): 1771-1781, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37462418

RESUMEN

Altered metabolic fingerprints of Diffuse large B-cell lymphoma, not otherwise specified (DLBCL NOS) may offer novel opportunities to identify new biomarkers and improve the understanding of its pathogenesis. This study aimed to investigate the modified metabolic pathways in extranodal, germinal center B-cell (GCB) and non-GCB DLBCL NOS from the head and neck. Formalin-fixed paraffin-embedded (FFPE) tissues from eleven DLBCL NOS classified according to Hans' algorithm using immunohistochemistry, and five normal lymphoid tissues (LT) were analyzed by high-performance liquid chromatography-mass spectrometry-based untargeted metabolomics. Partial Least Squares Discriminant Analysis showed that GCB and non-GCB DLBCL NOS have a distinct metabolomics profile, being the former more similar to normal lymphoid tissues. Metabolite pathway enrichment analysis indicated the following altered pathways: arachidonic acid, tyrosine, xenobiotics, vitamin E metabolism, and vitamin A. Our findings support that GCB and non-GCB DLBCL NOS has a distinct metabolomic profile, in which GCB possibly shares more metabolic similarities with LT than non-GCB DLBCL NOS.


Asunto(s)
Biomarcadores de Tumor , Linfoma de Células B Grandes Difuso , Humanos , Biomarcadores de Tumor/metabolismo , Linfoma de Células B Grandes Difuso/patología , Linfocitos B/metabolismo , Centro Germinal/metabolismo , Redes y Vías Metabólicas , Pronóstico
14.
Environ Sci Pollut Res Int ; 29(11): 16203-16212, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34647211

RESUMEN

The current work assessed the degradation degree and the degradation products derived from norfloxacin (NOR) and gentamicin (GEN) using iodosylbenzene and iodobenzene diacetate, in the presence of manganese porphyrin as catalysts. Better results for NOR degradation (> 80%) were obtained when more hydrophobic porphyrins were employed. ß-brominated manganese porphyrins showed a lower GEN degradation (~ 25%) than the non-brominated ones (~ 35%), probably due to their steric hindrance. In any case, complete mineralization was achieved neither for NOR nor for GEN, and the assignment of the generated products, complemented by the study of their toxicity, was an important step performed. From the obtained results, no correlation was found between the number of identified products and the reported toxicity value (rSpearman,NOR = 0.006; p value = 0.986 and rSpearman,GEN = - 0,198; p value = 0.583), which reinforces the idea of synergism and antagonistic phenomena. The higher degradation degree could have led to products of lower steric hindrance and easier penetration into the A. fischeri cells, which subsequently led to an increase in toxicity for these experiments. In most cases, the products presented higher toxicity than the original compound, which raises a concern about their occurrence in environmental matrices.


Asunto(s)
Manganeso , Porfirinas , Catálisis , Gentamicinas , Norfloxacino , Oxidación-Reducción
15.
Environ Pollut ; 268(Pt B): 115902, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33160736

RESUMEN

The aim of the present study was to assess the risks of four different pharmaceutical active compounds (PhACs; diazepam, metformin, omeprazole and simvastatin). Acute and chronic toxicities were studied using the bacterium Aliivibrio fischeri and the microalgae Pseudokirchneriella subcapitata; while the repellency and attractiveness were assessed by avoidance tests with juvenile Cypirinus carpio using a multi-compartmented exposure system. Omeprazole was found to be an acutely toxic drug (EC50: 0.015 mg/L), while the other PhACs, except simvastatin, showed some chronic toxicity. Regarding avoidance, simvastatin and omeprazole induced an escape response for 50% of the fish population at 0.032 and 0.144 mg/L, respectively; contrarily, diazepam was attractive, even at lethal concentrations, representing a dangerous trap for organisms. The toxicity of the PhACs seemed not to be directly related to their repellency; and the mode of action seems to determine the repellency or attractiveness of the chemicals. Contamination by PhACs is of concern due to the environmental disturbance they might cause, either due to their acute and chronic toxicity (at the individual level), repellency (at the ecosystem level: loss of local biodiversity) or attraction to potentially lethal levels.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Aliivibrio fischeri , Animales , Organismos Acuáticos , Daphnia , Ecosistema , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
16.
Front Oral Health ; 2: 677731, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35048024

RESUMEN

Aging is not a matter of choice; it is our fate. The "time-dependent functional decline that affects most living organisms" is coupled with several alterations in cellular processes, such as cell senescence, epigenetic alterations, genomic instability, stem cell exhaustion, among others. Age-related morphological changes in dental follicles have been investigated for decades, mainly motivated by the fact that cysts and tumors may arise in association with unerupted and/or impacted teeth. The more we understand the physiology of dental follicles, the more we are able to contextualize biological events that can be associated with the occurrence of odontogenic lesions, whose incidence increases with age. Thus, our objective was to assess age-related changes in metabolic pathways of dental follicles associated with unerupted/impacted mandibular third molars from young and adult individuals. For this purpose, a convenience sample of formalin-fixed paraffin-embedded (FFPE) dental follicles from young (<16 y.o., n = 13) and adult (>26 y.o., n = 7) individuals was selected. Samples were analyzed by high-performance liquid chromatography-mass spectrometry (HPLC-MS)-based untargeted metabolomics. Multivariate and univariate analyses were conducted, and the prediction of altered pathways was performed by mummichog and Gene Set Enrichment Analysis (GSEA) approaches. Dental follicles from young and older individuals showed differences in pathways related to C21-steroid hormone biosynthesis, bile acid biosynthesis, galactose metabolism, androgen and estrogen biosynthesis, starch and sucrose metabolism, and lipoate metabolism. We conclude that metabolic pathways differences related to aging were observed between dental follicles from young and adult individuals. Our findings support that similar to other human tissues, dental follicles associated with unerupted tooth show alterations at a metabolic level with aging, which can pave the way for further studies on oral pathology, oral biology, and physiology.

17.
Sci Total Environ ; 746: 141011, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32763601

RESUMEN

The presence of pharmaceutically active compounds (PhACs) in water supply systems has been generating great concern about their effects on the environment and human health. Twenty-eight PhACs were monitored during one year in four Brazilian water sources, aiming to understand the factors that influence their occurrence and removal in conventional drinking water treatment plants (DWTPs) and to assess the environmental and human health risks. Trace levels of PhACs were detected in surface and drinking water in all assessed water sources. Effects of seasonality and socioeconomic aspects were observed in PhACs occurrence, like their higher concentrations during winter and in locales with higher values of gross domestic product per capita and human development index. Betamethasone, prednisone, and fluconazole were the most commonly detected PhACs, and also presented the highest concentrations. However, they were not related to toxicological risks. Nonetheless, all surface waters were subject to toxicological risk owing to at least one PhAC. PhACs related to the highest toxicological risks were loratadine, atorvastatin, norfloxacin, caffeine, and ranitidine, however, all these PhACs presented low quantification frequency. DWTPs capacity to remove PhACs was only partial, so treated water was still contaminated with these compounds. Furthermore, atorvastatin presented a margin of exposure below 100, indicating possible risk for public health. Thus, additional advanced treatment steps should be considered to improve PhACs removal during drinking water treatment.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua/análisis , Purificación del Agua , Brasil , Monitoreo del Ambiente , Humanos , Medición de Riesgo , Abastecimiento de Agua
18.
Water Environ Res ; 81(5): 499-505, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19472941

RESUMEN

This work presents results from a detailed characterization of landfill leachates of different ages from a landfill in a major Brazilian city. This characterization consists of determining the molecular size distribution and the inert chemical oxygen demand (COD) and the biodegradability of both aerobic and anaerobic processes. Results show that leachate with a high COD concentration leachate has low biodegradability. A significant fraction of the COD is not characterized as protein, carbohydrate, or lipids, which reinforces the hypothesis that the remaining fraction was present in all leachate fractions (less than 1 kDa; between 1 and 10 kDa; between 10 and 100 kDa; and greater than 100 kDa) and is refractory. These results suggest that leachates with such characteristics require treatment systems that use physical-chemical processes as a pre- or post-treatment step to biological processes.


Asunto(s)
Oxígeno/metabolismo , Contaminantes Químicos del Agua/química , Biodegradación Ambiental , Tamaño de la Partícula , Microbiología del Suelo , Contaminantes Químicos del Agua/metabolismo
19.
Environ Technol ; 40(22): 2897-2905, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29580169

RESUMEN

The appropriate treatment of sanitary landfill leachate is one of the greatest challenges nowadays due to the large volumes of solid waste generated. Thus, the aim of this study is to evaluate the performance of different routes involving the integration of advanced oxidation processes based on Fenton's reagents (AOP-Fenton) and microfiltration (MF) and nanofiltration (NF) membrane processes for the treatment of landfill leachate. MF module configuration (submerged or sidestream) and MF and NF recovery rate were evaluated. The combination of AOP-Fenton, MF and NF proved to be an effective treatment for landfill leachate. High removal efficiencies of chemical oxidation demand (94-96%) and colour (96-99%) were obtained. The configuration named route 3, composed of MF of raw landfill leachate (MF1), POA-Fenton-MF2 of the MF1 concentrate and NF of both MF1 and MF2 permeates, showed a higher global water recovery and was responsible for lower waste generation. It was considered the best one in terms of environmental, technical and economical aspects.


Asunto(s)
Contaminantes Químicos del Agua , Peróxido de Hidrógeno , Oxidación-Reducción , Residuos Sólidos
20.
Environ Technol ; 40(17): 2267-2275, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29424282

RESUMEN

We evaluated the salinity reduction of the experimental saline solutions through ion uptake capacity of two plant species, purslane (PU) (Portulaca oleraceae) and water hyacinth (WH) (Eichhornia crassipes). These species were grown in experimental hydroponic units simulating a floating system. The hydroponic system contained treatments with three nutrient solutions identified as A1, A2, and A3 composed of fixed concentrations of macro and micronutrients to which three different concentrations of sodium chloride had been added. After the experimental period, physicochemical and volume changes in the saline nutrient solutions were evaluated. The relative growth rate results were similar for both plant species, but with lower consumption of hydroponic nutrient solutions by PU. Despite higher solution volume loss, regardless of the nutrient solution applied, WH had greater weekly estimated potential of reduction of macronutrients (calcium and magnesium; >50%); however, PU showed the best weekly potential reduction of sodium (36%) with solution A2. Therefore, both plants present potential to be used for salinity reduction in the natural conditions.


Asunto(s)
Eichhornia , Portulaca , Hidroponía , Salinidad , Cloruro de Sodio
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