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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Natural and anthropogenic influences on aluminium in the humic rich waters of northern Sweden /

Cory, Neil, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2006. / Härtill 4 uppsatser.
102

Investigating the efficacy of hydrogen peroxide agaisnt isolated environmental Escherichia coli strains

Giddey, Kirsten Francis 04 1900 (has links)
Thesis (MSc Food Sc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Surface water used for irrigation is often highly contaminated on a microbial level. Using contaminated surface water for the irrigation of fresh produce can lead to foodborne disease outbreaks and Escherichia coli has been a major cause of foodborne outbreaks associated with fresh produce over the past few years. There are many possible on-farm treatment options available to decrease the high microbial loads present in surface water, one of these is H2O2 and various factors can influence its use. The aim of this study was to determine the efficacy of H2O2 on different E. coli strains. Water from the Plankenburg River was sampled and treated with (250, 300 and 350 mg.L-1) H2O2 and the impact at 0, 30, 60, 90 and 120 min was then evaluated. It was found that the log reductions differed between samples. Log reductions ranged between 1.60 – 2.63 for Aerobic colony counts (ACC), total coliforms and Escherichia coli. The water was not considered safe for irrigation use although it had been treated with H2O2. Reference (ATCC) and environmental E. coli strains were individually treated with H2O2 (250, 300 and 350 mg.L-1) at 0, 30, 60, 90 and 120 min. Log reductions for the ATCC strains ranged between 2.13 – 5.48. This indicated a variation in H2O2 resistance between the different reference strains tested. Log reductions for the environmental E. coli strains ranged between 2.17 – 3.93. Escherichia coli M53 and MJ56 were the most resistant and most sensitive environmental strains to the H2O2 treatment, respectively. Once again it was observed that variations existed between the log reductions achieved for different strains. Overall, it was observed that the ATCC E. coli strains were more sensitive to the H2O2 treatments when compared the environmental strains. This indicates that ATCC strains should not be used for H2O2 treatment optimisation. Certain factors can influence the efficacy of H2O2 such as concentration and organic matter (chemical oxygen demand) present in the water. Different H2O2 concentrations were evaluated (50, 350, 700 and 1 000 mg.L-1) on two E. coli strains (M53 and W1371). Results indicated that 50 mg.L-1 was not effective as less than 1 log reduction was achieved after 120 min. When 350 and 700 mg.L-1 were used similar log reductions were achieved (1.78 – 2.27), which was not expected. Using 1 000 mg.L-1 was considered an effective concentration that resulted in no growth present after 120 min. Escherichia coli strain W1371 carried EPEC virulence factors (potential pathogen). This was included in the study in order to determine how a strain carrying virulence factors would react to H2O2. Escherichia coli W1371 was considered resistant to the H2O2 treatment and log reductions were similar to that achieved for M53. The catalase activity of the E. coli strains was studied to determine if a link existed between catalase activity and H2O2 resistance. Although a trend was observed between heat-stable catalase activity and H2O2 resistance, there were exceptions. It was concluded that high catalase activity does not always coincide with H2O2 resistance and that other mechanisms might also contribute to E. coli survival. Overall, it was observed that there are certain factors that influence the efficacy of H2O2 as a treatment option. It can be concluded that environmental E. coli strains are generally more resistant to the H2O2 treatment compared to ATCC E. coli strains, this needs to be considered when using H2O2 or other chemical disinfectants as a treatment option. / AFRIKAANSE OPSOMMING: Oppervlakwater wat gebruik word vir besproeiing is dikwels op ‘n mikrobiese vlak hoogs gekontamineer. Die gebruik van oppervlakwater vir die besproeiing van vars produkte kan tot die uitbraak van voedselgedraagde siektes lei. Escherichia coli was een van die hoofoorsake van voedselgedraagde uitbrake geassosieerd met vars produkte gedurende die laaste paar jaar. Daar is verskeie moontlike behandelingsmetodes op plaasvlak beskikbaar om die hoë mikrobiese las in oppervlakwater te verlaag. Een hiervan is waterstofperoksied (H2O2) en verskeie faktore kan die gebruik hiervan beïnvloed. Die doel van hierdie studie was om die doeltreffendheid van H2O2 op verskillende E. coli isolate te bepaal. Watermonsters uit die Plankenburg Rivier is behandel met drie konsentrasies H2O2 (250, 300 en 350 mg.L-1) en die impak is na 0, 30, 60, 90 en 120 minute geëvalueer. Daar is gevind dat die log reduksies tussen monsters verskil het. Log reduksies het gewissel tussen 1.60 en 2.63 vir aerobiese kolonietellings (AKT), totale kolivorme en E. coli. Selfs na H2O2 behandeling, is die water nie as veilig vir besproeiing beskou nie. Verwysingsisolate (ATCC) en omgewingsisolate van E. coli is afsonderlik met H2O2 behandel (250, 300 en 350 mg.L-1) vir 0, 30, 60, 90 en 120 minute. Log reduksies vir die ATCC isolate het gewissel tussen 2.13 en 5.48. Hierdie verskille dui op die variasies wat tussen die getoetste verwysingsisolate voorkom. Log reduksies vir die omgewingsisolate het gewissel tussen 2.17 en 3.93. Escherichia coli M53 en MJ56 was onderskeidelik die mees weerstandbiedende en mees sensitiewe verwysingsisolate wat getoets is. Verskille in log reduksies het daarop gedui dat isolaat variasies voorkom. In geheel is dit gevind dat die ATCC E. coli isolate meer sensitief was vir die H2O2 behandelings vergeleke met die omgewingsisolate. Dit toon dat die ATCC isolate nie gebruik moet word vir H2O2 behandeling optimering nie. Sekere faktore, soos die konsentrasie en organiese materiaal (chemiese suurstof vereiste) in die water, kan die doeltreffendheid van H2O2 behandeling beïnvloed. Verskillende H2O2 konsentrasies is geëvalueer (50, 350, 700 en 1000 mg.L-1) op twee E. coli isolate (M53 en W1371). Resultate dui daarop dat 50 mg.L-1 nie effektief was nie omdat minder as 1 log reduksie behaal is na 120 minute. Toe 350 en 700 mg.L-1 gebruik is, is soortgelyke log reduksies (1.78 – 2.27) teen verwagting in behaal. Die gebruik van 1000 mg.L-1 is as ‘n effektiewe behandeling beskou aangesien daar geen groei na 120 minute teenwoordig was nie. Escherichia coli isolaat W1371 besit EPEC virulensie faktore (potensiële patogeen). Dit is in die studie ingesluit ten einde te bepaal hoe ‘n isolaat met virulensie faktore sou reageer op H2O2. Escherichia coli W1371 is as weerstandbiedend teen die H2O2 behandeling beskou en log reduksies was soortgelyk aan die van M53 . Die katalase aktiwiteit van die E. coli isolate is bestudeer om te bepaal of ʼn skakel bestaan tussen katalase aktiwiteit en H2O2 weerstandbiedendheid. Alhoewel ‘n tendens waargeneem is tussen hitte-stabiele katalase aktiwiteit en H2O2 weerstandbiedendheid, was daar uitsonderings. Die gevolgtrekking was dat hoë katalase aktiwiteit nie altyd saamval met H2O2 weerstandbiedendheid nie en dat ander meganismes ook mag bydra tot E. coli oorlewing. In geheel is dit waargeneem dat daar sekere faktore is wat die doeltreffendheid van H2O2 as ‘n behandelingsmetode beïnvloed. Daar is gevind dat omgewingsisolate van E. coli in die algemeen meer weerstandbiedend is teenoor H2O2 behandeling in vergelyking met ATCC E. coli isolate. Dit moet in ag geneem word wanneer H2O2 of ander chemiese ontsmettingsmiddels oorweeg word as ʼn behandelingsopsie.
103

Study on Distribution and Behavior of PFOS (Perfluorooctane Sulfonate) and PFOA (Perfluorooctanoate) in Water Environment / 水環境におけるPFOS(ペルフルオロオクタンスルホン酸)およびPFOA(ペルフルオロオクタン酸)の分布と挙動に関する研究 / ミズ カンキョウ ニ オケル PFOS ( ペルフルオロオクタン スルホンサン ) オヨビ PFOA ( ペルフルオロオクタンサン ) ノ ブンプ ト キョドウ ニ カンスル ケンキュウ

Lien, Nguyen Pham Hong 25 September 2007 (has links)
学位授与大学:京都大学 ; 取得学位: 博士(工学) ; 学位授与年月日: 2007-09-25 ; 学位の種類: 新制・課程博士 ; 学位記番号: 工博第2850号 ; 請求記号: 新制/工/1419 ; 整理番号: 25535 / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13379号 / 工博第2850号 / 新制||工||1419(附属図書館) / 25535 / UT51-2007-Q780 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 藤井 滋穂, 教授 伊藤 禎彦 / 学位規則第4条第1項該当
104

Toxicology and molecular epidemiology of microbes detected in surface water in the Western Cape: The Impact of Informal Settlement

Maboza, Ernest J.M. January 2013 (has links)
>Magister Scientiae - MSc / Informal settlements are often implicated in surface water pollution with faecal matter. In most instances faecal pollution in the associated surface waters persists despite improvements in sewage removal infrastructure. This study evaluates the importance of investigating the water quality of the Plankenbrug River before it reaches Khayamnandi settlement by comparing water quality in spring and in winter upstream (Pre-Khayamnandi) and downstream (Post- Khayamnandi) from the settlement. In this study, faecal indicator bacteria (Escherichia coli and total coliforms) were enumerated using Chromocult agar. E. coli was further characterized with analytical profiling index (API) and haemolysis assays. Both Pre- and Post-Khayamnandi were not significantly different from each other for both total coliforms and E. coli in winter. Pre-Khayamnandi had between 105 and 108 cfu/100 ml for total coliforms while Post-Khayamnandi had total coliform colony count between 106 and 107 cfu/100 ml. E. coli also exhibited a similar pattern with slightly higher counts at Post-Khayamnandi with colony counts from 104 to 107 and 105 to 107 cfu/100 ml. Spring microbial count demonstrated a significant difference to winter counts within each test site (p ≤ 0.01) and across the two sites (p ≤ 0.05). Both total coliforms and E. coli were 102 fold higher at Post-Khayamnandi than at Pre-Khayamnandi in spring. The API assay demonstrated significant difference (p ≤ 0.05) between the two test sites. Pre- Khayamnandi predominantly had two different profiles while Post-Khayamnandi had three. These profiles represented five distinct E. coli biotypes. Sorbitol and sucrose tests within the API assay demonstrated significant differences (p ≤ 0.05) between the two test sites. The prevalence of sorbitol fermenters at Pre-Khayamnandi was 100% while at Post-Khayamnandi it was 73%. Pre-Khayamnandi also demonstrated a significantly higher prevalence of sucrose fermenters than Post-Khayamnandi at 100% and 59% respectively. These differences indicated dissimilar sources of faecal contamination around these sites. Differences in the distributions of sorbitol and sucrose fermenting biotypes demonstrate different toxicity potentials across these two test sites. The haemolysis assay demonstrated that 9% of isolates were haemolytic with reference to both known α- and β-haemolyitic streptococci at Post-Khayamnandi. At Pre-Khayamnandi there was a higher percentage of α- and β-haemolyitic species, 29% and 28%, respectively. Post- Khayamnandi and Pre-Khayamnandi were significantly different from each other with reference to both α- and β-haemolysis (p ≤ 0.05). These haemolytic activities also demonstrate different toxicity potentials across the two sites. In conclusion Khayamnandi contributes to an already heavy faecal load in the Plankenbrug River. Thus remedial measures to maintain high surface water quality of Plankenbrug River should be directed upstream from the Khayamnandi settlement as well as within the settlement equally. This study recommends integration of microbial loads with programs such as the National Microbial Monitoring Program of South Africa to drive prioritization process in directing reclaiming of water quality, inter alia.
105

Hodnocení vlivu krajinné struktury na znečištění povrchových vod v CHKO Křivoklátsko s využitím ArcSWAT / Impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area using ArcSWAT

Hanzlová, Markéta January 2018 (has links)
The topic of thesis deals with a hydrological model SWAT used for impact assessment of landscape structure on surface water pollution in Krivoklatsko protected area. For this purpose using ArcSWAT in the ArcGIS environment there were built hydrological models of three watersheds of various landscape structure located in the area of interest. The measured data of nitrate were used for these models. Concentration of nitrates in the surface waters were simulated by using these models in the period from 2003 until mid-2014. The statistical evaluation of the models including actual landscape structure did not show satisfactory match of the simulated values with the measured values. Due to the uncertainties of the model, including insufficient quantity of measured nitrates, it was not possible to expect exact results. After validation of basic models, it was important to create new models that would include various scenarios of landscape structure organization. New versions represented changes in the use of land classified as arable land in pasture or mixed forests, in the area around the stream to 250 m and 500 m. Modelling of the impact of individual scenarios on the structure of the landscape structure on nitrate concentrations there was displayed a positive effect of grassing and afforestation of...
106

A salinidade das águas superficiais e sua interferência nas condições sócio-econômicas na sub-bacia do rio Cabaceiras - Curimataú paraibano / A salinity of surface water and its interference in socio-economic conditions in sub-basin river Cabaceiras - Curimataú paraibana

Assis, Edvania Gomes de 21 August 2002 (has links)
Made available in DSpace on 2015-05-07T14:49:19Z (GMT). No. of bitstreams: 1 parte2.pdf: 2851369 bytes, checksum: 7d81168f19872afa8d8f8bf527ba97df (MD5) Previous issue date: 2002-08-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The semi-arid region of the north-east Brazil, is characterized by drought, with low rainfall indices, high evaporation, high incoming solar radiation, and soils susceptible to salinization. In this scenario, populations seek the areas close to the ponds (locally known as açudes ), aiming to achieve satisfactory life condition and development. Ponds are found practically everywhere in the sertão . The ponds accumulate water during the rainy period, but not for a long time, because of periodic droughts and high evaporation. In the sub-basin of River Caraibeiras, in the municipality of Barra de Santa Rosa, there are two noteworthy ponds: Poleiro and Curimataú, both planned for water supply. It was aimed in the present study to estimate the water salinity indices of those ponds and how they affect socio-economic conditions in that region. Results obtained from the water physical-chemical analyses showed a high salt concentration, in the ponds, limiting the water consumption by humans, animals and crop irrigation. Such situation alters the habits of human communities and affects directly the socioeconomic condition in that region / O Semi-Árido do Nordeste brasileiro é caracterizado pela carência hídrica, baixos índices pluviométricos, alta evaporação e insolação e solos tendentes à salinização. É neste cenário que as populações procuram as áreas próximas aos açudes, com o objetivo de manter uma condição de vida satisfatória ao seu desenvolvimento. A presença de açudes ocorre em praticamente todo o sertão. Estes acumulam água no período chuvoso, não permanecendo assim por muito tempo, devido à ocorrência de secas periódicas e alta evaporação. Na Sub-bacia do Rio Caraibeiras, no município de Barra de Santa Rosa, dois açudes se destacam: o Poleiro e o Curimataú, com fins de abastecimento público. O presente estudo tem como objetivo avaliar o índice de salinidade das águas desses reservatórios e sua influência nas condições sócioeconômicas da região. Os resultados obtidos através de análises físico-químicas da água, registraram uma grande concentração de sais nas águas dos açudes, restringindo o uso para o consumo humano, dessedentação dos animais e na irrigação. Esta situação modifica os hábitos das comunidades e interfere diretamente nas condições socioeconômicas da região
107

Srážkově - odtokové parametry vybraných povodí Stropnice / Rainfall - runoff parameters selected basin Stropnice

FRAŇKOVÁ, Diana January 2010 (has links)
Dissertation work rainfall-drainage parameters on chosen river-basin Stropnice is dealing with measurement of drainage value of surface water on five specific profiles in the area of Horní Stropnice. The goal was discovery and analysis of information on the river-basin Bedřichovský, Pasecký and Váckový stream, Humenická dam and in closure profile at Tomkův mill in the years 2007 {--} 2010, where there were monitoring heights of water level. After substitution into discharge-rating curve were scoring flow rate for individual parts of river-basins and examination of influence Humenická dam on flow rate wave in the closure profile. Between the upper specific profiles of individual streams above Humenická dam and specific profile by the Tomkův mill there was not found any influence of Humenická dam on flow wave in the river basin of Stropnice.
108

Monitoramento de agrotóxicos em áreas irrigadas por pivô central na microbacia do Tijunqueiro, município de Morrinhos, Goiás / Pesticides monitoring in irrigated areas by central pivot in the Tijunqueiro Watershed municipality of Morrinhos, Goias

Aderbal Almeida Rocha 12 August 2011 (has links)
A importância dos agrotóxicos para o sistema de produção agrícola é indiscutível, uma vez que constituem parte dos insumos básicos. No entanto, é fundamental que sejam adequadamente utilizados para a preservação da qualidade não só do produto cultivado, mas também dos próprios recursos naturais, especialmente o solo e a água. Neste estudo, foi realizado o monitoramento dos agrotóxicos utilizados em lavouras irrigadas por pivô central, na microbacia do Tijunqueiro, município de Morrinhos, estado de Goiás, que apresentaram potencial de contaminação ambiental (critérios da Agência de Proteção Ambiental dos Estados Unidos EPA, índice GUS Groundwater Ubiquity Score, método GOSS e do Instituto Brasileiro de Recursos Naturais Renováveis e não Renováveis IBAMA) e sensíveis ao espectrômetro de massas (LC-MS/MS Cromatografia líquida acoplada ao espectrômetro de massas), no período entre fevereiro de 2009 e setembro de 2010, em amostras de águas superficial e subsuperficial, peixes e sedimentos. Os ingredientes ativos (agrotóxicos) monitorados foram: acefato, atrazina, azoxistrobina, buprofezina, carbofurano, ciproconazole, clorpirifós, difeconazole, diurom, imidacloprido, malationa, metamidofós, metolacloro, metribuzim, monocrotofós, monuron, tiametoxam e triazofós. Amostras de água superficial foram coletadas a montante e a jusante da represa do Tijunqueiro; água subsuperficial em poços piezométricos perfurados no entorno da área irrigada; peixes e sedimentos foram coletados na represa do Tijunqueiro. A técnica de extração em fase sólida (SPE) foi utilizada para extrair os ingredientes ativos das amostras de água, dispersão da matriz na fase sólida (DMFS) para as amostras de sedimentos e QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) para as amostras de peixes. Os métodos multiresíduos utilizados foram adequados e eficientes para a análise e quantificação por LC-MS/MS. Verificou-se que todas as curvas analíticas apresentaram coeficiente de correlação superior a 0,99 e as recuperações foram satisfatórias (70 % a 120 % de recuperação) para a maioria dos ingredientes ativos monitorados. Nas amostras de água superficial, peixe e sedimentos, não foram detectados resíduos dos ingredientes ativos monitorados e 25,7 % das amostras de água subsuperficiais apresentaram contaminação por atrazina / The importance of pesticides to the agricultural system production is indisputable, since they are part of the basics inputs, however, it is essential that they be used properly to be preserved not only the quality of the growing product, but also of their own natural resources, especially soil and water. In this study was conducted the pesticides monitoring used on crops irrigated with a central pivot in the Tijunqueiro watershed municipality of Morrinhos, state of Goias, who had potential for environmental contamination (criteria of the Environmental Protection Agency from the United States EPA, index of GUS - Groundwater Ubiquity Score, GOSS method and Brazilian Institute of Environment and Renewable Natural Resources IBAMA) and sensitive to the mass spectrometer (LC-MS/MS Liquid Chromatography coupled to mass spectrometer) on the period between February 2009 and September 2010, in samples of surface and groundwater, fish and sediment. The active ingredients (pesticides) monitored were acephate, atrazine, azoxistrobin, buprofezin, carbofuran, cyproconazol, chlorpyriphos, difenoconazol, diuron, imidacloprid, malathion, metamidophos, metolachlor, metribuzin, monocrotophos, monuron, thiamethoxan and triazophos. Surface water samples were collected upstream and downstream of the Tijunqueiro dam; groundwater in piezometric wells drilled around the irrigated area; fishes and sediments were collected in the Tijunqueiro dam, The solid phase extraction technique (SPE) was used to extract the analytes from water samples, dispersive solid phase extraction (dSPE) for the sediments samples and QuEChERS (Quick, Easy, Cheap, Effective, Rugged) for the fishes samples. Multiresidue methods used in the study were adequate and efficient for the analysis and quantifications by LC-MS/MS. Was found that all the analytical curves showed correlation coefficients greater than 0,99 and the recoveries were satisfactory (70 % a 120 % of recovery) for most of the active ingredients studied. In the surface water samples, sediments and fish were not detected residues of the active ingredients monitored and 25.7 % groundwater samples showed atrazine contamination
109

Investigação de agrotóxicos carbamatos em águas superficiais bruta e tratada no Rio Branco em Roraima

Leonidas de Holanda Farias Filho 29 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os agrotóxicos vêm sendo amplamente utilizados no combate a inúmeros grupos de insetos, vegetais, fungos e demais seres vivos que diminuem o rendimento agrícola em cultivos variados, também podem ser manipulados contra vetores de enfermidades para seres humanos e outros animais. Em muitos casos, o seu uso indiscriminado, causa problemas ambientais aparentemente imperceptíveis, mas de grande magnitude na biota impactada. Sendo alguns grupos de agrotóxicos, utilizados em pequenas doses, causam a morte e podem acumular-se nos tecidos animais e vegetais, sua decomposição pode ser muito lenta possibilitando alcançarem regiões distantes de onde foram utilizados. São transportados pelas águas subterrâneas e superficiais, e em algumas ocasiões, dispersados pelos ventos atmosféricos. Sua detecção e quantificação se dá por técnicas e equipamentos de elevada sensibilidade, pois sua distribuição no meio ambiente, na maioria das vezes, está em pequenas concentrações. Neste trabalho foram coletadas águas superficiais do rio Branco e na Estação de Tratamento da cidade de Boa Vista e em seguida submetido à técnica de extração Líquido-Sólido, SPE- off-line, para pré-concentração dos pesticidas e depois a Cromatografia Líquida de Alta Eficiência - CLAE para a sua separação e quantificação. Foram detectados os agrotóxicos carbamatos: aldicarbe sulfona, carbofurano, carbaril, hidroxi carbofurano, metomil e nafitol com suas concentrações sempre acima do recomendado pela Portaria 2.914/11 MS e Resolução CONAMA 357/05. A água tratada distribuída a população apresentou traços de três tipos de carbamatos acima do permitido pela legislação brasileira, Aldicarbe sulfona 9,10 mg L-1, Carbaril 1,0 mg L-1 e metomil 32 mg L-1. Foram feitos testes de recuperação dos analitos carbaril e metomil, na qual apresentaram resultados de 85 e 105 % respectivamente, para o método utilizado, demonstrado que o procedimento é confiável. Os resultados apresentados aumentam a preocupação em torno dos impactos que os agrotóxicos podem causar ao meio ambiente e a saúde das pessoas que utilizam as águas do rio Branco diariamente. / Pesticides have been widely used to combat numerous groups of insects, plants, fungi and other living beings that reduce crop yield in various crops, can also be manipulated against disease vectors to humans and other animals. In many cases, their indiscriminate use, causes environmental problems seemingly imperceptible, but of great magnitude in biota impacted. As some groups of pesticides used in small doses, can cause death and accumulate in animal and plant tissues, their decay can be very slow allowing reach distant regions from which they were used. Are transported by groundwater and surface water, and on some occasions, dispersed by atmospheric winds. Its detection and quantification is done by standard techniques and equipment with high sensitivity since its distribution in the environment, in most cases, is in small concentrations. In this work we collected surface water of the Branco river and Treatment Station of the city of Boa Vista and then subjected to extraction technique Liquid - Solid -off -line SPE for pre-concentration of pesticides and then the High Performance Liquid Chromatography efficiency - HPLC for their separation and quantification. Pesticides were detected carbamates aldicarb sulfone, carbofuran, carbaryl, hydroxicarbofuran, methomyl and naphytol always with their concentrations above recommended by Ordinance 2.914/11 MS and CONAMA Resolution 357 / 05. The treated water distributed population showed traces of three types of carbamates above those permitted by Brazilian law, Aldicarb sulfone 9.10 mg L-1, Carbaryl 1.0 mg L-1 and methomyl 32 mg L-1. Tests were made to recover the analytes carbaryl and methomyl, which showed results of 85 and 105 %, respectively, for the method used, demonstrated that the procedure is reliable. The results presented raise concern about the impact that pesticides can cause to the environment and health of people who use the waters of the Branco river daily.
110

Study on Contamination of Perfluorinated Compounds (PFCs) in Water Environment and Industrial Wastewater in Thailand / タイにおける水環境および工業廃水のペルフルオロ化合物(PFCs)汚染に関する研究 / タイ ニ オケル ミズ カンキョウ オヨビ コウギョウ ハイスイ ノ ペルフルオロ カゴウブツ ( PFCs ) オセン ニ カンスル ケンキュウ

Kunacheva, Chinagarn 24 September 2009 (has links)
PFCs are used in a wide variety of industrial and commercial applications for more than 50 years. Among variation of PFCs, Perfluorooctane sulfonate (PFOS) (CF3(CF2)7SO3-) and perfluorooctanoic acid (PFOA) (CF3(CF2)6COO-) are the most dominant PFCs. In May 2009, PFOS, its salts and perfluorooctane sulfonyl fluoride (PFOSF) are designated as new Persistent Organic Compounds (POPs) which are resistant, bio-accumulating, and having potential of causing adverse effects to humans and environment (IISD, 2009). However, products containing PFCs are still being manufactured and used, which could be the main reason why they are still observed in the environment and biota (Berger et al., 2004; Saito et al., 2003; Sinclair et al., 2004). The study is focused on the PFCs contamination in water and industrial wastewater around the Central and Eastern Thailand, where is one of the major industrialized areas in the country. The samplings were conducted in major rivers, Chao Phraya, Bangpakong and Tachin River. PFCs were contaminated in all rivers. The average total PFCs were 15.10 ng/L, 18.29 ng/L and 7.40 ng/L in Chao Phraya, Bangpakong and Tachin River, respectively. PFOS and PFOA were the predominant PFCs in all samples. The total of 118.6 g/d PFOS and 323.6 g/d PFOA were released from the three rivers to the Gulf of Thailand. The survey was also conducted in small rivers, reservoirs, and coastal water around Eastern Thailand, where many industrial zones (IZ) are located. The geometric mean (GM) concentration of each PFC was ranged from 2.3 to 107.7 ng/L in small rivers, 2.2 to 212.2 ng/L in reservoirs, and 0.8 to 41.1 ng/L in coastal water samples. The higher PFCs contaminations were detected in the surface water around the industrial zones, where might be the sources of these compounds. Field surveys were also conducted in ten industrial zones (IZ1 – IZ10) to identify the occurrences of PFCs from in industries. The recovery rates of PFCs in the samples indicated that the matrix interference or enhancement was an important problem in PFCs analysis. The elevated concentrations were detected in electronics, textile, chemicals and glass making industries. Total PFCs concentrations in the influent of WWTP were ranged from 39.6 to 3, 344.1 ng/L. Ten industrial zones released 188.41 g/d of PFCs. All of the treatment processes inside industrial zones were biological processes, which were reported that they were not effective to remove PFCs. The influence of industrial discharges was affected not only the rivers and reservoirs but also in the coastal water. The PFCs in rivers and reservoirs were discharged to the Gulf of Thailand, which is the important food source for Thai people and exports. Due to the problems in industrial wastewater analysis, several optimizing options were applied in PFCs analytical method especially in Solid Phase Extraction (SPE) procedure. The combination of PresepC-Agri and Oasis®HLB was the better option for analyzing PFCs in water samples. The optimum flow rate for loading the samples was 5 mL/min. Methanol (2 mL) plus Acetronitrile (2 mL) was the effective way to elute PFCs from the cartridges. The specific solvent percentages to elute each PFCs were identified for both water and industrial wastewater samples. The matrix removal methods by using Envi-Carb and Ultrafilter were effective for different types of industrial wastewater samples. PFCs were detected in surface waters, which are the sources of tap and drinking water for the people in Central and Eastern Thailand. The surveys were conducted in Bangkok city. Samples were collected from water treatment plants (WTPs), tap water, and drinking water. PFCs were detected in all tap water and drinking water samples. PFOS and PFOA concentrations in raw water of WTP were found 4.29 ng/L and 16.54 ng/L, respectively. The average PFOS and PFOA concentrations in tap water were detected 0.17 and 3.58 ng/L, respectively. The tap water results also showed that PFOS and PFOA concentrations were not similarly detected in all area in the city. PFOA were detected higher in the western area, while PFOS concentration was quite similar in all areas. Overall, it can be concluded that the current treatment processes were not completely remove PFCs. Nevertheless, PFCs in particulate phase were effectively removed by the primary sedimentation and rapid sand filtration. Elevated PFCs were found in the industrial zones (IZ2 and IZ5). To understand the distribution and fate of PFCs during industrial wastewater process, PFCs mass flows were studied. Higher PFCs in adsorbed phase were detected only in activated sludge and some influent samples. In IZ2, PFOA loading in the dissolved phase increased after activated sludge process by 5%. There was no degradation of PFOA inside the polishing pond. The highest loading to the treatment plant was PFOS with the loading of 2, 382 mg/d and 1, 529 mg/d in dissolved and adsorbed phase, respectively. Unlike PFCAs that showed no removal in the treatment process, PFOS were decreased during the treatment processes with 36% in the activated sludge process and 36% in the polishing pond. The predominant in this IZ5 was PFOS. The increasing of PFOS was also found in this treatment plant dissimilar to IZ2. PFOS was increasing by 45% in dissolved phase and 47% in adsorbed phase. All of PFCs in this industrial zone were detected higher in the effluent, indicated that PFCs’ precursors should be the major effects of this contamination. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14930号 / 工博第3157号 / 新制||工||1473(附属図書館) / 27368 / UT51-2009-M844 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 清水 芳久, 教授 藤井 滋穂 / 学位規則第4条第1項該当

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