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1.
Braz. arch. biol. technol ; 63: e20180573, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132185

ABSTRACT

Abstract This work reports the study of the potential application of Zn/TiO2 catalysts, obtained by the sol-gel method, in processes of environmental decontamination through the reactions of photodegradation of textile dye, followed by electrospray mass spectrometry. The catalysts synthesis was performed according to a 2² factorial design with repetition at the central point. The characterization techniques used were: N2 adsorption measurements (BET method), scanning electron microscopy with energy dispersive X-ray (MEV/EDS), X-ray diffraction and point of zero charge (PZC). The photocatalytic tests were performed in batch in the presence of sunlight, and to evaluate the degradation kinetics study, a rapid direct injection electrospray mass spectrometry (DI-ESI-MS) method has been developed. By the photocatalytic tests, the calcination temperature of 400 °C has shown the best results of discoloration for the reactive Orange-122 dye (99.76%) in a reaction time of 2h. The discoloration kinetics were a pseudo-first order, and a statistical analysis was performed to investigate the effects of the variables and to optimize the conditions of discoloration to the dye. After the reactional time of 2 h, an ion of m/z 441.5 was detected by ESI-MS, indicating that the photocatalytic process was effective for the degradation of the dye to secondary compounds.


Subject(s)
Azo Compounds/toxicity , Biodegradation, Environmental , Decontamination/methods , Tandem Mass Spectrometry/methods , Environmental Restoration and Remediation/methods , Waste Water , Photochemistry , Textiles/toxicity , Microscopy, Electron, Scanning , Catalysis , Catalytic Domain , Spectrometry, Mass, Electrospray Ionization , Coloring Agents , Photobioreactors , Models, Theoretical
2.
Rev. argent. microbiol ; 51(1): 39-46, mar. 2019. ilus
Article in English | LILACS | ID: biblio-1003279

ABSTRACT

Tributyltin (TBT) is recognized as a major environmental problem at a global scale. Haloalkaliphilic tributyltin (TBT)-degrading bacteria may be a key factor in the remediation of TBT polluted sites. In this work, three haloalkaliphilic bacteria strains were isolated from a TBT-contaminated site in the Mediterranean Sea. After analysis of the 16S rRNA gene sequences the isolates were identified as Sphingobium sp. HS1, Stenotrophomonas chelatiphaga HS2 and Rhizobium borbori HS5. The optimal growth conditions for biodegradation of TBT by the three strains were pH 9 and 7% (w/v) salt concentration. S. chelatiphaga HS2 was the most effective TBT degrader and has the ability to transform most TBT into dibutyltin and monobutyltin (DBT and MBT). A gene was amplified from strain HS2 and identified as TBTB-permease-like, that encodes an ArsB-permease. A reverse transcription polymerase chain reaction analysis in the HS2 strain confirmed that the TBTB-permease-like gene contributes to TBT resistance. The three novel haloalkaliphilic TBT degraders have never been reported previously.


Se considera a la tributiltina (TBT) como un problema medioambiental serio a escala global. Las bacterias haloalcalifílicas degradadoras de TBT pueden constituir un factor clave para remediar áreas contaminadas con dicho xenobiótico. En este estudio se aislaron 3 cepas de bacterias haloalcalifílicas procedentes de un sitio contaminado con TBT en el mar Mediterráneo. Tras analizar las secuencias del gen de 16S del ARNr, se identificaron los aislados como Sphingo-bium sp. HS1, Stenotrophomonas chelatiphaga HS2 y Rhizobium borbori HS5. Las condiciones de crecimiento óptimas para la biodegradación de TBT por parte de las 3 cepas fueron pH 9 y 7% (p/v) de concentración de sal. S. chelatiphaga HS2 fue el degradador de TBT más efectivo, con capacidad de transformar la mayor parte de ese compuesto en dibutiltina y monobutiltina (DBT y MBT). Se amplificó un gen de la cepa HS2, que fue identificado como tipo TBTB-permeasa, que codifica para una ArsB permeasa. Un análisis de la cepa HS2 por reacción en cadena de la polimerasa con transcriptasa inversa (RT PCR) confirmó que el gen TBTB-permeasa contribuye a la resistencia al TBT. Estos 3 nuevos degradadores haloalcalifílicos de TBT no habían sido reportados previamente.


Subject(s)
Bacteria/isolation & purification , Environmental Restoration and Remediation/methods , Biodegradation, Environmental , Mediterranean Sea/epidemiology , Polymerase Chain Reaction/methods , Reverse Transcription/genetics , Environmental Restoration and Remediation/analysis
3.
São Paulo; s.n; 2017. 131 p.
Thesis in Portuguese | LILACS | ID: biblio-875738

ABSTRACT

A presença de contaminação por substâncias perigosas no solo e na água subterrânea acarreta inúmeros problemas, tais como: risco à saúde humana e aos ecossistemas; comprometimento da água para abastecimento público; e redução do valor econômico e da função social do terreno. Embora as tecnologias de remediação sejam aplicadas para resolver problemas ambientais e de saúde pública, estas também podem gerar externalidades ambientais negativas como consumo de energia e recursos naturais; desequilíbrio do ciclo da água; erosão do solo; e emissão de gases de efeito estufa. Tendo em vista a recente ocorrência com áreas contaminadas na Universidade de São Paulo (USP) o presente trabalho visou elaborar um plano de gestão sustentável para uma dessas áreas localizada no campus USP da Capital, contribuindo com o Programa de Políticas Ambientais, sob coordenação da Superintendência de Gestão Ambiental da USP. A metodologia de pesquisa foi baseada em revisão bibliográfica sobre remediação sustentável e construção sustentável e em a análise qualitativa das ações, práticas e lições aprendidas de casos bem sucedidos de gestão das áreas contaminadas com elementos sustentáveis como subsídio para elaboração do plano. A partir da caracterização de quatro áreas contaminadas existentes no campus USP da Capital, foi selecionada a área da USP Leste para estudo de caso para promover o uso de práticas sustentáveis em campus universitário, de tal forma que proteja a saúde humana e minimize os impactos ambientais adversos. Com o intuito de buscar melhorias à gestão do campus, por meio da inserção da sustentabilidade na gestão da contaminação da USP Leste, a elaboração do plano de gestão sustentável considerou as especificidades locais nas práticas sustentáveis a serem implementadas, conforme as necessidades e diretrizes da USP. As soluções propostas incluíram a combinação do planejamento das fases de investigação e remediação com o design da construção de edifícios, que possam trazer benefícios ambientais, econômicos e sociais a todas as partes interessadas, tais como redução de custos a longo prazo relacionados à redução do consumo de energia e eletricidade pela implantação de sistemas de energia renováveis para fornecimento de energia elétrica ao sistemas de ventilação de metano


The presence of contamination by hazardous substances in soil and groundwater causes numerous problems, such as risk to human health and ecosystems; water impairment as drinking water; and reduced economic value and social function of the land. Although remediation technologies solve environmental and public health issues, they can also generate negative environmental externalities such as energy and natural resources consumption; imbalance of water cycle; soil erosion; and greenhouse gas emissions. Due to recent occurrence with contaminated areas at the University of São Paulo (USP) the present work aims to develop a sustainable management plan for one of these areas located on the USP Capital campus, contributing to Program of Environmental Policies, coordinated by the Superintendence of Environmental Management of USP. The research methodology was based on literature review about sustainable remediation and construction; and qualitative analysis of actions, practices and lessons learned applied on successful case studies of contaminated sites management with sustainable elements as subsidy for elaboration of the plan. Based upon a characterization of four contaminated areas located on USP Capital campus, the site of USP Leste was selected as case study in order to promote the use of sustainable practices on campus, through an approach that protects human health and minimizes adverse environmental impacts. In order to seek improvements to the campus management by sustainability integration in contamination management of USP Leste, the elaboration of sustainable management plan considered local specificities on sustainable practices to be implemented, according to the needs and guidelines of USP. The proposed solutions included the planning of investigation and remediation stages with the construction design of buildings that can bring environmental, economic and social benefits to all stakeholders, such as long-term cost savings related to the reduction of energy consumption and electricity by the implementation of renewable energy systems to supply electricity to methane ventilation systems


Subject(s)
Biodegradation, Environmental , Environmental Management , Environmental Pollution , Environmental Restoration and Remediation/methods , Universities , Buildings , Conservation of Natural Resources , Construction Industry
4.
Electron. j. biotechnol ; 19(1): 29-32, Jan. 2016. ilus
Article in English | LILACS | ID: lil-781167

ABSTRACT

Background: Microbial-induced remediation of Zn2+ pollution based on the capture and utilization of carbon dioxide was investigated. In this study, carbon dioxide was absorbed and transformed into carbonate ions under the enzymatic action of Paenibacillus mucilaginosus, which was being utilized to mineralize Zn2+. Results: The compositional and morphological properties of the precipitations were studied using Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The thermal properties of the precipitates were investigated by thermogravimetric-differential scanning calorimetry (TG-DSC). The FTIR results confirmed that the functional groups of the precipitates were CO3² − and OH−. The XRD and EDS patterns showed that basic zinc carbonate could be obtained successfully by Microbial-induced remediation. The SEM micrographs demonstrated that the precipitates were in the nanometer range with sizes of 100-200 nm and were sphere-like in shape. Conclusions: The TG-DSC results showed that weight loss of the precipitates occurred around 253°C. The FTIR and TG-DSC results were in accord with the XRD and EDS results and proved again that the precipitates were basic zinc carbonate. This work thus demonstrates a new method for processing Zn2+ pollution based on the utilization of carbon dioxide.


Subject(s)
Zinc/metabolism , Carbon Dioxide/metabolism , Environmental Restoration and Remediation/methods , Paenibacillus , Spectrometry, X-Ray Emission , Thermogravimetry , X-Ray Diffraction , Spectroscopy, Fourier Transform Infrared , Biomineralization
5.
Bol. micol. (Valparaiso En linea) ; 30(1): 2-9, jun. 2015. ilus, graf
Article in Spanish | LILACS | ID: biblio-868795

ABSTRACT

La biotecnología ambiental recurre a organismos capaces de reducir los niveles de metales pesados, entre ellos el Cr(VI), contenido en residuos y efluentes agroindustriales. El objetivo del trabajo fue estudiar la biorremediación de un residuo como pulpa de limón contaminada con Cr(VI) y el efecto del metal sobre el crecimiento fúngico. Se utilizaron tres hongos filamentosos como Aspergillus niger; Penicillium expansum y P. islandicum para remediar pulpa de limón (residuo) contaminada con Cr(VI) (50 mg/L) que se realizó en las siguientes condiciones de cultivo: la pulpa se suplementó con urea, 0,006; (NH4) 2SO4, 0,012; KH2PO4,0,003 y KCl, 0,001 g/ g; 105 conidios/g, a pH 2,5, 30°C y 96 h de incubación. Se estudió el efecto tóxico de diferentes concentraciones (5; 10; 20 y 50 mg/L) del metal sobre el desarrollo del hongo de mayor eficiencia de remediación (Ef. por ciento). Aspergillus niger; obtuvo mayor EF. de remediación (97 por ciento) respecto a Penicillium expansum (95 por ciento) y P. islandicum (94 por ciento), del residuo contaminado con 50 mg/L de Cr(VI). Se determinó que la presencia de Cr(VI) y no su concentración estimuló la maduración temprana (48 h) de los conidios (blancos a negros) de A. niger, sin que se observe alteraciones en el micelio con respecto al control (72h), desarrollado en la pulpa sin el metal. En conclusión, A. niger fue más resistente y presentó altas Ef. de remediación de Cr(VI) de residuos sólidos, este proceso es una alternativa a las tecnologías físico-químicas, debido que los microorganismos pueden remover selectivamente diferentes iones de zonas contaminadas.


Environmental biotechnology uses organisms capable of reducing levels of heavy metals, including the Cr (VI), contained in waste and agro-industrial effluents. The objective of this work was to study bioremediation of waste contaminated with Cr(VI) lemon pulp and the effect of the metal on the fungal growth. We used three filamentous fungi such as Aspergillus niger; Penicillium expansum and P. islandicum to remedy pulp from lemon (residue) contaminated with Cr(VI) (50 mg/L) that was conducted in the following conditions of cultivation: the pulp is supplemented with urea, 0.006; (NH4) 2SO4, 0.012; KH2PO4, 0.003 and KCl, 0.001 g / g; 105 conidia/g, at pH 2.5, 30 ° C and 96 h of incubation. We studied the toxic effect of different concentrations (5, 10, 20 and 50 mg/L) of the metal on the development of the fungus increased efficiency of remediation (Ef. percent). Aspergillus niger; obtained greater EF. remediation (97 percent) with respect to Penicillium expansum (95 percent) and P. islandicum (94 percent), 50 mg/L of Cr (VI)-contaminated waste. It was determined that the presence of Cr (VI) and not its concentration stimulated early maturation (48 h) of conidia (white on black) from A. niger, unless you observe alterations in the mycelium as compared to the control (72 h), developed in the pulp without the metal. In conclusion, A. niger was stronger and presented high Ef. remediation of Cr (VI) waste, this process is an alternative to physico-chemical technologies, due to the micro-organisms be removed selectively different ions from contaminated areas.


Subject(s)
Humans , Aspergillus niger/growth & development , Biodegradation, Environmental , Chromium/toxicity , Penicillium/growth & development , Solid Waste/analysis , Environmental Restoration and Remediation/methods , Fungi/growth & development , Metals, Heavy/toxicity , Contaminant Removal/methods , Hazardous Substances/toxicity
6.
Journal of School of Public Health and Institute of Public Health Research. 2013; 10 (4): 91-104
in Persian | IMEMR | ID: emr-138538

ABSTRACT

Problems related to conventional Fenton oxidation, including neccesity of having a low pH and production of considerable amounts of sludge, have prompted researchers to consider chelating agents to improve the pH operating range and iron nano-oxide particles to reduce excess sludge. The main objective of this study was to remove pyrene from contaminated soils by a modified Fenton oxidation method at neutral pH. Experiments were conducted using various concentrations of H2O2 [0-500 mM], iron nano-oxides [0-60 mM], reaction times [0.5-24 hours] and several chelating agents, namely, sodium pyrophosphate, ethylene diamine tetra-acetic acid, sodium citrate, fulvic and humic acids, to eliminate pyrene from soil [concentrations of 100-500 mg/kg]. The efficiency of removal of pyrene at an initial concentration of 100 mg/kg was 99% at the following reaction conditions: H2O2 and iron nano-oxide concentrations of 300 mM and 30 mM, respectively; pH=3; and a reaction time of 6 hours. The initial pyrene concentration of 100 mg/kg decreased to 7 mg/kg at optimum conditions using sodium pyrophosphate as the chelating agent at pH 7. The modified Fenton oxidation method, using iron nano-oxide at optimum conditions as defined in this research, is an efficient alternative for chemical remediation or pre-treatment of soils contaminated with pyrene at neutral pH


Subject(s)
Soil Pollutants/analysis , Hydrogen Peroxide/chemistry , Iron/chemistry , Environmental Restoration and Remediation/methods , Industrial Waste , Chelating Agents , Sewage , Hydrogen-Ion Concentration
7.
Bol. micol. (Valparaiso En linea) ; 27(1): 3-7, jul. 2012. graf
Article in Spanish | LILACS | ID: lil-679647

ABSTRACT

Aspergillus nigerGC1 es un microorganismo potencial para ser utilizado en procesos de biorremediación de níquel (II). A las concentraciones ensayadas de níquel divalente (1,5 y 3,0 mg/l) no se produjo inhibición del crecimiento celular. A pH 4,5 se obtuvo una eficiencia de 60 y 73 por ciento, en la biorremediación de 1,5 y 3,0 mg/l de níquel (II) respectivamente, mayor al valor obtenido a pH 5,5. Se propone un mecanismo de detoxificación del Ni(II) en solución acuosa por la célula fúngica, sugiriendo que en primer lugar, el Ni (II) se adsorbe a la pared celular del hongo, y en segundo lugar, se produce la absorción del metal al interior celular, para ser posiblemente almacenado o secuestrado, en la estructura vacuolar, a fin de disminuir la toxicidad en el citoplasma celular.


Aspergillus niger GC1 is a potential microorganism to be used in processes of bioremediation of nickel (II). To concentrations of divalent nickel (1.5 and 3.0 mg/l) tested there was inhibition of cell growth. To pH 4.5 was achieved an efficiency of 60 and 73 percent in the bioremediation of 1.5 and 3.0 mg/l of nickel (II), respectively, more than the value obtained at pH 5.5. Proposed a mechanism of detoxification of the Ni (II) in aqueous solution by the fungal cell, suggesting that firstly, the Ni (II) was adsorbs to the cell wall of the fungus, and second, occurs the absorption of metal into the cell, to be possibly stored or sequestered in the vacuolar structure, in orden to reduce the toxicity in the cell cytoplasm.


Subject(s)
Aquatic Suspension , Aspergillus niger , Environmental Pollution , Metals, Heavy , Nickel , Environmental Restoration and Remediation/methods
8.
Rev. colomb. biotecnol ; 14(1): 20-30, ene.-jun. 2012. ilus, graf, tab
Article in English | LILACS | ID: lil-656937

ABSTRACT

Recalcitrance and contamination in Mahogany (Swietenia macrophylla King) and Spanish cedar (Cedrela odorata L.) stem tissues are the main causes of its ineffective in vitro propagation. The objectives of this research were: a) to evaluate sodium hypochlorite (NaOCl) and plant preservative mixture (PPM®) as surface disinfectants and/or added to the culture medium for the in vitro establishment of nodal explants taken from 10-year-old Mahogany and Spanish cedar plants, and b) to evaluate the in vitro response of such explants treated with N6-benzylaminopurine (BAP) (0, 2.2, 4.4, 8.8, 17.7 μM), silver nitrate (AgNO3) (0, 3 mg l-1), activated charcoal (0, 1 g l-1) and vented caps. All the experiments were arranged in a completely randomized design. The NaOCl at 15%, for 20 min, as a surface sterilization or PPM® at 2 ml l-1 into the culture medium, were the best treatments to reduce contamination for both species. For Mahogany explants, BAP at 17.7 μM resulted in higher percentages of bud breaks than Spanish cedar (64% and 25%, respectively). Leaves on elongated shoots dropped off by 20 days after starting the explants in culture and neither the activated charcoal nor the AgNO3 alone or combined prevented leaf abscission. The AgNO3 decreased contamination, but also increased leaf abscission. Bud breaks was two-fold higher for nodal explants established in vessels with vented caps than with normal caps. Mahogany nodal explants were easier to surface sterilize and more buds broke from BAP treated explants than Spanish cedar treated explants in the in vitro establishment.


La contaminación y la recalcitrancia de tejidos de tallo de Caoba (Swietenia macrophylla King) y Cedro español (Cedrela odorata L.) son las causas principales de su inefectiva micro-propagación. Los objetivos de la investigación fueron: a) evaluar el hipoclorito de sodio (NaClO) y una mezcal preservadora de plantas (PPM®) como desinfectantes superficiales y/o agregados al medio de cultivo para el establecimiento in vitro de explantes nodales de Caoba y Cedro español de 10 años de edad; b) evaluar la respuesta in vitro de tales explantes tratados con N6-benzylaminopurine (BAP) (0, 2.2, 4.4, 8.8, 17.7 μM), nitrato de plata (AgNO3) (0, 3 mg l-1), carbón activado (0, 1 g l-1) y tapas porosas. Los experimentos fueron establecidos bajo un diseño completamente al azar. La contaminación se redujo en ambas especies con NaOCl al 15% durante 20 min como desinfección superficial o con PPM® (2 ml l-1) agregado al medio de cultivo. El mayor porcentaje de brotación de explantes se obtuvo con BAP a 17.7 μM en caoba (64%) comparado con cedro (25%). Los brotes se defoliaron a los 20 días de cultivo y ni el carbón activado ni el AgNO3, solos o combinados evitaron la defoliación. El AgNO3 disminuyó la contaminación, pero incrementó la defoliación. La brotación fue dos veces mayor en los explantes nodales establecidos en recipientes con tapas porosas que cuando se utilizaron tapas normales. Los explantes nodales de Caoba respondieron mejor a la desinfección superficial y a los tratamientos de BAP comparados con los de Cedro español en el establecimiento in vitro.


Subject(s)
Environmental Pollution , Disinfection , In Vitro Techniques , Environmental Restoration and Remediation/analysis , Environmental Restoration and Remediation/statistics & numerical data , Environmental Restoration and Remediation/methods , Air Pollution , Biological Contamination/analysis , Biological Contamination/statistics & numerical data , Biological Contamination/methods , Biological Contamination/prevention & control , Physical Contamination/analysis , Physical Contamination/statistics & numerical data , Physical Contamination/methods , Physical Contamination/prevention & control , Environmental Pollution
9.
Braz. j. biol ; 70(4,supl.0): 1245-1247, Dec. 2010.
Article in English | LILACS | ID: lil-570553

ABSTRACT

The Sinos River Basin is often mentioned as a highly degraded watershed. A series of impacts on water quality, soil and air has been reported in this environment on a recurring basis over the years. This situation of environmental degradation has its origins in a process of huge economic development uncoupled from environmental conservation concerns. The intense consequent urbanization observed for the municipalities within the watershed was not preceded by urban planning proper zoning. The time has arrived for initiatives in scientific research in the Sinos River basin that are applicable to a more efficient and integrated management and recovery of the basin. In this article, a set of targets for research is suggested which the authors consider as the main priorities for the next few years, aiming for better knowledge and better management of the watershed. Some are still in course, while others have to be initiated as soon as possible.


A bacia hidrográfica do Rio dos Sinos é frequentemente citada como altamente degradada. Uma série de impactos sobre a qualidade da água, do solo e do ar tem sido relatada neste ambiente de forma recorrente ao longo dos anos. Esta situação de degradação ambiental tem suas origens em um processo de grande desenvolvimento econômico, desacoplado de preocupações com a conservação ambiental. A intensa urbanização observada para os municípios dentro da bacia hidrográfica não foi precedida pelo zoneamento e planejamento urbano adequados. É chegado o momento para iniciativas no domínio da investigação científica na bacia do Rio dos Sinos que tragam resultados aplicáveis a uma gestão mais eficiente e integrada da recuperação da bacia. Neste artigo, um conjunto de metas para a pesquisa são sugeridas como as principais prioridades para os próximos anos, visando um melhor conhecimento e uma melhor gestão da bacia. Alguns já estão em curso, enquanto outros têm de ser iniciados o mais rapidamente possível.


Subject(s)
Humans , Conservation of Natural Resources/methods , Environmental Monitoring/methods , Environmental Restoration and Remediation/methods , Rivers , Brazil
10.
Braz. j. biol ; 70(4): 977-986, Nov. 2010. ilus, graf, tab
Article in English | LILACS | ID: lil-569160

ABSTRACT

In 2000 there was an oil spill at the Getúlio Vargas Refinery (REPAR) in Paraná. Nearly five years after contamination and the use of bioremediation, a study was carried out to identify the effects of the contaminated soil and the bioremediated soil on the germination and initial growth of C. xanthocarpa. The experiment was established with soil from REPAR, with three treatment groups: contaminated soil (C), bioremediated soil (B) and uncontaminated soil (U); with five repetitions of 50 seeds each. There was no significant difference in the percentage of germination and the speed of germination index. The production of total biomass (30 - 60 days) and shoot biomass (60 days) was greater in the bioremediated soil compared to the other treatments. The averages for the root biomass were lower in the contaminated soil than in the bioremediated soil. The shoot length and the total length of the seedling in the contaminated soil and uncontaminated soil were lower than in the bioremediated soil.


Em 2000, ocorreu um vazamento de petróleo na área da Refinaria Getúlio Vargas (REPAR), no Paraná. Após cerca de cinco anos da contaminação e utilização do processo de biorremediação, pretendeu-se identificar os efeitos do solo contaminado e do solo biorremediado na germinação e no crescimento inicial de C. xanthocarpa. O experimento foi montado com solo da REPAR, com três tratamentos - solo contaminado (C), solo biorremediado (B), solo não contaminado (U) - e cinco repetições com 50 sementes cada. Não houve diferença significativa na porcentagem e no índice de velocidade de germinação. A produção de biomassa total (30 - 60 dias) e biomassa da parte aérea (60 dias) foram maiores no tratamento biorremediado em relação aos demais tratamentos. As médias para a biomassa da raiz foram menores no solo contaminado do que no solo biorremediado. O comprimento da parte aérea e o comprimento total da plântula no solo contaminado e no não contaminado foram menores do que no biorremediado.


Subject(s)
Environmental Restoration and Remediation/methods , Germination/physiology , Myrtaceae/growth & development , Petroleum , Soil Pollutants , Biomass
11.
Braz. j. biol ; 70(3,supl.0): 689-695, Oct. 2010. ilus
Article in English | LILACS | ID: lil-564125

ABSTRACT

Water in the XXI century has become the primary factor for sustainable development, eradication of poverty and reversal of ecosystem degradation. Increasing water demand for agriculture and urbanisation, combined with pollution, eutrophication and amplification of the stochastic character of climatic processes, increases water limitations for ecosystems and societies. The transdisciplinary science of Ecohydrology, which has been developed in the framework of the International Hydrological Programme of UNESCO, provides a systemic approach, to regulate hydrology-ecosystem-society interplay towards: 1) slowing down the transfer of water from the atmosphere to the sea, still considered as a priority to reduce the severity of floods and droughts impact; 2) reducing input and regulating the allocation of excess nutrients and pollutants to aquatic ecosystems, toward reversing ecosystems degradation and improvement of human well being; and 3) harmonisation of ecosystem potential with societal needs within the framework of IWRM.


A Água no século XXI tornou-se o fator primordial para o desenvolvimento sustentável, a erradicação da pobreza e as iniciativas para reverter à degradação dos ecossistemas. O aumento da demanda de águas para a agricultura e urbanização, eutrofização e poluição e a amplificação do caráter estocástico dos processos climáticos aumenta o limite de água disponível para os ecossistemas e as sociedades. A ciência transdisciplinar da Ecohidrologia, que se desenvolve no arcabouço do Programa Hidrológico Internacional da UNESCO, proporciona uma abordagem sistêmica na regulação das interações hidrologia-ecossistema e sociedade. Esta abordagem dá-se através dos seguintes processos e ações: 1) iminuindo a transferência da água da atmosfera para os oceanos, considerando-se esta ação como prioridade para reduzir a severidade das enchentes e secas; 2) Reduzindo a eutrofização e poluição dos sistemas aquáticos continentais revertendo a degradação do ecossistema e melhorando o bem estar humano; e 3) Harmonização do potencial dos ecossistemas com as necessidades da sociedade no arcabouço do programa Gerenciamento Integradas de Recursos Hídricos.


Subject(s)
Conservation of Natural Resources/methods , Ecosystem , Environmental Restoration and Remediation/methods , Fresh Water , Water Pollution/prevention & control , Biodiversity , Eutrophication , Water Supply
12.
J. appl. oral sci ; 18(2): 121-126, Mar.-Apr. 2010. ilus, tab
Article in English | LILACS | ID: lil-550403

ABSTRACT

Dental amalgam residues are probably the most important chemical residues generated from clinical dental practice because of the presence of heavy metals among its constituents, mainly mercury and silver. OBJECTIVE: The purpose of this study was to develop an alternative method for the recovery of silver residues from dental amalgam. MATERIAL AND METHODS: The residue generated after vacuum distillation of dental amalgam for the separation of mercury was initially diluted with 32.5 percent HNO3, followed by precipitation with 20 percent NaCl. Sequentially, under constant heating and agitation with NaOH and sucrose, the sample was reduced to metallic silver. However, the processing time was too long, which turned this procedure not viable. In another sequence of experiments, the dilution was accomplished with concentrated HNO3 at 90ºC, followed by precipitation with 20 percent NaCl. After washing, the pellet was diluted with concentrated NH4OH, water and more NaCl in order to facilitate the reaction with the reducer. RESULTS: Ascorbic acid was efficiently used as reducer, allowing a fast reduction, thus making the procedure viable. CONCLUSIONS: The proposed methodology is of easy application and does not require sophisticated equipment or expensive reagents.


Subject(s)
Dental Waste , Dental Amalgam/chemistry , Environmental Restoration and Remediation/methods , Silver/isolation & purification , Ascorbic Acid/chemistry , Fractional Precipitation/methods , Medical Waste Disposal , Nitric Acid/chemistry , Reducing Agents/chemistry , Sodium Chloride/chemistry , Sodium Hydroxide/chemistry , Sucrose/chemistry
13.
Iranian Journal of Health and Environment. 2010; 3 (3): 309-318
in Persian | IMEMR | ID: emr-122372

ABSTRACT

Arsenic is one of the most toxic and dangerous elements in drinking water that with increase in its application in agriculture, development of applications in agriculture, livestock, medicine, industry and other cases its entry to water resources and environment is much easier. Arsenic is a poisonous, cumulative substance and inhibitor of SH group enzymes and various studies revealed a significant correlation between high concentrations of arsenic in drinking water and liver cancer, nasal cavity cancer, lungs, skin, bladder and kidney cancer in men and women and prostate and liver in men. The aim of this was survey of arsenic removed from water using dissolved air floatation mechanism. At present study in first step for determination best conditions of arsenic removal by dissolved air floatation method, optimum amount of coagulants determined and then synthetic solution of arsenic [50, 100 and 200 micro g/L] prepared using sodium arsenate. In third step arsenic removal efficiency under various variables such as arsenic concentration, flocculation and floatation time and saturation pressure were analyzed. Finally residual arsenic concentration was determined by the silver diethyl dithiocarbamate method. Effect of optimum condition on arsenic removal efficiency at various initial concentration 50, 100 and 200 microg/Lshowed that the best coagulant for removal of arsenic is polyaluminumchloride. Also maximum efficiency [99.4%] was obtained in initial concentration equal 200 microg/L. It can be concluded that dissolved air floatation method with poly aluminum chloride as coagulant have high efficiency for arsenic removal even at high concentrations and therefore this method can be used for removal of arsenic from water as a suitable and safe option


Subject(s)
Water Pollutants, Chemical/isolation & purification , Environmental Restoration and Remediation/methods , Filtration/methods , Air
14.
Iranian Journal of Health and Environment. 2009; 2 (2): 114-123
in Persian | IMEMR | ID: emr-93666

ABSTRACT

Leachate is one of the landfill products and also a wastewater bearing the most advers effects on the environment. Biological methods are usually employed for treatment of young leachate [1-2 years] wich is of high concentration of organic compounds with low molecular weight. However these methods are not approprate for mature leachate [5-10years] due to having high rate of compounds with molecular weight and the presence of materials resistant to biodegradation and toxic compounds. Advanced oxidation process such as Fenton reagent used in treatment or biodegrability improvement of strong wastewater. In the present study the degrability improvement of mature leachate through oxidation fenton process in bench scale and in batch reactor has been investigated. The samples have been taken from Ahwaz landfill and factors such as initial COD and BOD, pH, BOD5/COD were studies as degradability, the amount of Hydrogen Peroxide, Fe[II], optimal reaction time and optimal pH. The highest amount of COD removal was observed in PH=3-3.5 and 90 minutes of reaction time. H2O2=29700mg/land Fe2+=16500 mg/l in [Fe2+]/[H2O2]=1/14.8 molarity ratio were obtained as optimal amounts BOD5/COD was equal to 0.38. This study indicates that Fenton oxidation enhances the biodegradability of leachate


Subject(s)
Environmental Restoration and Remediation/methods , Oxidation-Reduction , Hydrogen Peroxide/chemistry , Organic Chemicals/metabolism , Waste Disposal, Fluid/methods , Refuse Disposal , Iron/chemistry
15.
Rev. biol. trop ; 56(3): 1053-1061, sep. 2008. graf, tab
Article in Spanish | LILACS | ID: lil-637846

ABSTRACT

Experimental tolerance to boron of the plant species Nicotiana glauca, Jacaranda mimosifolia, Tecoma stans, Medicago sativa y Spinacea oleracea in Argentina. The activity of boron industries is a punctual and diffuse source of air, soil and water pollution. Therefore, it is a priority to study possible ways of reducing this impact. A relatively new technology for reducing soil pollution is phytoremediation, which uses plants and associate microorganisms. The first step in phytoremediation is to detect tolerant plant species, which is the objective of this work. A laboratory experiment to assess the germination, survival and growth of different species at different boron concentrations was carried out following a factorial design with two factors: plant species and boron concentration. Boron concentrations were determined at the beginning and the end of the experiment, taking into account substrates with and without vegetation. We found significant differences for treatment, species and the interaction species*treatment. N. glauca, M. sativa and J. mimosifolia were the most tolerant species. The other species had a decrease in the response variables, with the concentration of the pollutant. All the species had a low survival at the highest boron concentration. The reduction in boron concentration at the end of the experiment was higher in the 30 ppm treatment with M. sativa and the lower was registered in the 20 ppm treatment with J. mimosifolia and in 30 ppm with T. stans and S. oleraceae. We conclude that N. glauca, M. sativa and J. mimosifolia can be considered in remediation plans. Rev. Biol. Trop. 56 (3): 1053-1061. Epub 2008 September 30.


La actividad de las industrias borateras constituye una fuente puntual y difusa de contaminación del aire, suelo y aguas superficiales y profundas. Por lo tanto, el estudio y experimentación acerca de las posibles formas de contrarrestar este impacto constituye una prioridad. Una técnica relativamente nueva para descontaminar suelos es la fitorremediación, que emplea plantas y microorganismos asociados. El primer paso es detectar las especies vegetales tolerantes, lo que constituye el objetivo de este trabajo. Se realizó un experimento en laboratorio para evaluar la germinación, la supervivencia y el crecimiento de distintas especies en diferentes concentraciones de boro. Al comienzo y al final del experimento se determinó la concentración de boro en el sustrato para cada tratamiento y para sustratos con y sin vegetación. Se encontraron diferencias significativas debidas al tratamiento, la especie y la interacción especie *tratamiento. M. sativa, N. glauca y J. mimosifolia fueron las especies de mayor tolerancia al boro. Las otras especies presentaron una disminución en todas las variables-respuesta en función de la concentración del contaminante. Todas presentaron una baja supervivencia en la máxima concentración. La disminución de boro fue máxima en el tratamiento de 30 ppm de boro con M. sativa y la menor se registró en los tratamiento de 20 ppm de boro con J. mimosifolia y de 30 ppm de boro con T. stans y S. oleraceae. Se concluye que N. glauca, M. sativa y J. mimosifolia podrían considerarse como prometedoras en remediación.


Subject(s)
Magnoliopsida/drug effects , Boron/toxicity , Germination/drug effects , Argentina , Magnoliopsida/growth & development , Bignoniaceae/drug effects , Bignoniaceae/growth & development , Environmental Restoration and Remediation/methods , Medicago sativa/drug effects , Medicago sativa/growth & development , Spinacia oleracea/drug effects , Spinacia oleracea/growth & development , Time Factors , Tobacco/drug effects , Tobacco/growth & development
16.
J Environ Biol ; 2008 May; 29(3): 357-61
Article in English | IMSEAR | ID: sea-113485

ABSTRACT

Growth and nutrient uptake of seven tree species were evaluated with the goal of selecting the species that can be used for wastewater enhancement by dendro-purification, or green tree filtering, and for restoration of riparian woodlands. Trees were grown in pots with an inert mixture of perlite and vermiculite and irrigated with either nutrient solution or treated wastewater We measured the effects of species and irrigation water on biomass and nutrient content of leaves, stems and roots. For most of the species, treated wastewater had a positive effect on final biomass and above ground: below ground ratio compared to that of nutrient solution. However, growth of Cupressus sempervirens and Populus nigra were inhibited by water sodium concentration. Nerium oleander, Tamarix africana and Vitex agnus-castus were the species with the greatest final biomass. Pistacia terebinthus had the highest nitrogen and phosphorus content in leaves, stems and roots, while N. oleander and V. agnus-castus showed the best potassium accumulation. In general, P. terebinthus, N. oleander, T. africana and V. agnus-castus were the best qualified species for purification of wastewater.


Subject(s)
Ecosystem , Environmental Restoration and Remediation/methods , Water Pollutants , Wood
17.
Article in English | IMSEAR | ID: sea-114147

ABSTRACT

This article discusses the problem of iron and manganese contamination, the adverse effects and available control methods. The presence of iron and manganese in water causes serious commercial and health problems. Various treatment methods are available to treat water contaminated with these elements. However, catalytic media is an excellent choice particularly increasing given the preference for non-chemical water treatment. INDION ISR and BIRM are the most popularly used synthetically manufactured catalytic media.


Subject(s)
Environment , Environmental Monitoring/methods , Environmental Restoration and Remediation/methods , Ferric Compounds/analysis , Hydrogen-Ion Concentration , Ion Exchange , Iron/analysis , Manganese/analysis , Models, Chemical , Oxygen/chemistry , Risk , Water/analysis , Water Pollutants , Water Pollutants, Chemical , Water Supply
18.
Article in English | IMSEAR | ID: sea-114092

ABSTRACT

Cypermethrin is a pyrethroid pesticide and is used in the control of a wide range of insects on crops like vegetables, cereals, maize etc. In the present study, the adsorption efficiency of coconut shell based activated carbon for the removal of color and organic matter from cypermethrin pesticide manufacturing industrial wastewater was investigated. Effect of carbon dosage, pH and contact time on the removal of COD was also studied. Equilibrium and kinetic studies were carried out and the data was fitted in Freundlich and Langmuir models. The study proved that activated coconut shell carbon (acc) is an efficient adsorbent for treatment of cypermethrin industrial wastewaters under study.


Subject(s)
Adsorption , Carbon/analysis , Charcoal/chemistry , Cocos/chemistry , Environmental Restoration and Remediation/methods , Industrial Waste , Industry , Kinetics , Particle Size , Pyrethrins/analysis , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Water Purification/methods
19.
J Environ Biol ; 2006 May; 27(2 Suppl): 311-6
Article in English | IMSEAR | ID: sea-113631

ABSTRACT

Phytotoxicity, microbial activity, plant uptake and microbial degradation were examined using Rumex crispus in TNT and/or cadmium contaminated columns (TNT: 100 mg/kg of soil and Cd: 10 mg/kg of soil). The growth of plants was significantly inhibited by TNT, but not by Cd. The microbial activity was highly increased by plant root growth, decreased by Cd, and slightly reduced by TNT. The plant uptake of Cd was relatively well in Cd-contaminated column, but lowered by TNT in TNT+Cd-contaminated column. The microbial degradation of TNT occurred much faster in planted columns than in unplanted columns with minor effect of Cd (less 2-ADNT was produced). Therefore, it may be effective to treat TNT first and then Cd using phytoremediation in the TNT plus Cd contaminated sites.


Subject(s)
Cadmium/metabolism , Environmental Restoration and Remediation/methods , Plants/drug effects , Soil Microbiology , Soil Pollutants/metabolism , Trinitrotoluene/metabolism
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