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Spatio-temporal variations of fluoride in surface and ground water : a case study of the Umgeni Water operational area, KwaZulu-Natal.Ramjatan, Ashadevi. January 2002 (has links)
In September 2000 water fluoridation became mandatory in South Africa. Since then water service providers like Umgeni Water (UW), a bulk water supply authority in the KwaZulu-Natal (KZN) province of South Africa began the process of implementing the legislation. This study was undertaken to establish the spatio-temporal variations of fluoride concentrations in surface and ground waters within the Umgeni Operational Area, to establish whether these waters would require fluoridation or defluoridation to meet a fluoride concentration of 0.70 mglf, and to assess the potential impacts of water fluoridation. Baseline fluoride concentrations of surface and ground water: It was concluded that the fluoride concentration of all sample types (rivers, dams, water works raw and final waters, wastewater influent and effluents, and boreholes), except pollution point sources, is less than O.S; mglR, 50 percent of the time. Some rivers (Mshazi, KwaNyuswa, KwaNgcolosi,·Mshwati and the MgoShongweni) exhibited high fluoride concentrations, while someboreholes also exhibited high fluoride concentrations. Temporal Variations and Seasonality: There are seasonal variations in the fluoride concentrations for surface waters, with higher fluoride concentrations in winter than in summer (64 out of 125 occasions). This low fluoride concentration in summer can be attributed to the dilution effects caused by rainfall runoff. Identification of "Hot Spots": "Hot Spots", sites where the fluoride concentration exceeds 1 mglR are present within the study area, for surface and borehole water. For surface water, the MgoShongweni exhibited fluoride concentrations in excess of 1mglRat least 75% of the time. The KwaNgcolosi and Mshwati exhibited fluoride concentrations In excess of 1mglR at least 25% of the time, while the Mshazi and the KwaNyuswa exhibited fluoride concentrations in excess of 1mglR only 5% of the time. The storm water discharge below AECI had high fluoride concentrations in excess of 1mg/R at least 20% of the time and the concentrations exceeded the fluoride concentration for seawater (1.4 mglf) at least 5% of the time. Of the 286 boreholes sampled, 17 boreholes (6% of all boreholes sampled) had fluoride levels in excess oft mglf . The impacts of long term consumption of water from these boreholes could range from slight mottling of the dental enamel in sensitive individuals (boretioles JD26, C29, H19, CB7, 112/1, 69/5, Thembeni 108 and EC (Thembeni 105, Keats Drift boreholes 1 and 2). Spatial patterns and possible sources of high fluoride concentrations: With respect to spatial patterns, relatively high concentrations of fluoride (300 IJglR to 1000 IJglR) can be found in surface water in the Msunduzi river, the Mgeni river downstream of the Msunduzi confluence and along the coastal belt. No spatial patterns are evident with respect to borehole water. For surface water, high fluoride concentrations in the Mshazi, KwaNyuswa and the KwaNgcolosi streams (inflows to the Inanda dam) appear to be associated with the catchment geology. The ~igh fluoride concentrations in Mshwati and the MgoShongweni are most likely as a result of industrial activities in the respective catchments. For borehole water, high fluoride concentrations may be attributed to catchment geology. Additional fluoride dosaqe ' at water treatment works: Since the fluoride concentrations at the water works were low (mean ranging between 0.5 mglf to 0.38 mglf) , fluoride would need to be added to meet the fluoride standard of 0.7 mgl£ . For most of the water works, the additional fluoride (sodium fluoride) requirement to meet the fluoride standard of 0.7 mgl£, ranged from 1.201 kglMRto 1.555 kg/MR. For the water works, Imfume and Umzinto, the additional fluoride , requirement is 0.768 kg/MR and 0.109 kg/MR respectively. In final water, the fluctuations in fluoride concentrations observed would translate to continuous testing being required to maintain optimal dosing of fluoride. Comparison of influent and effluent fluoride concentrations at wastewater works: There was no evidence of fluoride removal at the Mpophomeni Wastewater Works . There was evidence of 22.4% fluoride removal at the DarvHI Wastewater Works possibly due to the activated sludge treatment process at the wastewater works. Future fluoride levels in surface water that will receive return flows: Once water fluoridation is implemented, the Darvill Wastewater Works would receive fluoridated return flows, and discharge its fluoride rich effluent into the Msunduzi river. The average monthly fluoride road discharged from Darvill Wastewater Works would increase from 0.23 tons to 1.46 tons, an additional 1.23 tons per month on the aquatic environment of the Msunduzi river. The sludge fluoride load, disposed to land, could increase from 4 056 tons/month to 27 863 tons/month, which implies an increase in the fluoride runoff potential from the sludge-lands to the Msunduzi river. Number of people in sensitive groups that could be affected by water fluoridation: A significant number of people in KZN could be sensitive to water fluoridation. This has been estimated to be at least one third of KZN's population that are HIV infected. Recommendations were made and the most important ones are as follows: In the light of the large number of people, one-third the population of KZN, that is HIV positive and therefore could be sensitive to fluoridated water, it is recommended that the South African legislation mandating water fluoridation be withdrawn. Examination of the most recent literature indicated a significant lack of confidence in the best available studies that researched the safety and efficacy of water fluoridation. In the light of this it is recommended that the South African Department of Health re-examine and withdraw its legislation that mandates water fluoridation. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002.
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Defluoridation of groundwater using vermiculite modified with hexadecyltrimethylammonium: a case study of Siloam Village, Limpopo Province, South AfricaOlogundudu, Tayo Oladipo 05 1900 (has links)
MENVSC / Department of Hydrology and Water Resources / See the attached abstract below
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Le cycle hydrosocial et la fluoration de l'eau : la production des eaux fluoréesAmado Rohten, Rodrigo 04 1900 (has links)
La fluoration artificielle de l’eau est une méthode employée en tant que moyen de
prévention de la carie dentaire. Il s’agit d’un traitement de l’eau dont le but est d’ajuster de
façon « optimale » la concentration en fluorure dans l’eau potable pour la prévention de la
carie dentaire, par l’ajout d’un composé fluoré. La fluoration de l’eau fait l’objet d’un débat
de société depuis le début des années 1950. La théorie du cycle hydrosocial nous invite à réfléchir sur la manière dont l’eau et la société se définissent et se redéfinissent mutuellement dans le temps et dans l’espace. Cette
théorie nous permet d’aborder l’étude du sujet de la fluoration avec une nouvelle
perspective d’analyse. Il y a peu d’études en sciences sociales qui portent sur le sujet de la
fluoration, généralement abordé d’un point de vue des sciences de la santé. Nous
proposons de décrire le processus de production des eaux fluorées dans un contexte
hydrosocial. Ce mémoire est structuré en quatre chapitres. Nous commençons par familiariser le lecteur
avec la théorie du cycle hydrosocial. Ensuite, nous faisons une mise en contexte de la
fluoration de l’eau, d’une part en présentant un état des lieux, et d’autre part en présentant
ce en quoi consiste la pratique de la fluoration de l’eau. Après avoir familiarisé le lecteur
avec les thèmes généraux concernant la fluoration de l’eau, nous proposons de reconstituer
une histoire hydrosociale de la fluoration. Cette histoire nous permet de mettre en
évidence les relations hydrosociales desquelles découle la production des eaux fluorées.
L’histoire hydrosociale de la fluoration comporte une phase contemporaine que nous
abordons en présentant les principales idées de l’opposition à la fluoration artificielle de
l’eau à l’aide notamment d’une analyse iconographique d’images portant sur le thème de la
fluoration. Finalement, nous discutons des implications de la théorie du cycle hydrosocial
pour étudier la problématique de la fluoration. / Artificial water fluoridation is a method used as a way of preventing tooth decay. It is a
water treatment that consists in adjusting the fluoride concentration in water to a
“optimal” level in order for it to work in preventing tooth decay. Water fluoridation has
been subject to social debate since the early 50’s. The theory of the hydrosocial cycle brings us to think about the ways water and society are mutually defined and redefined by one another in time and space. This theory allows us to
study the subject of water fluoridation with a new perspective. There are few works in
social sciences that are about water fluoridation, a subject which is generally approached
by a health science point of view. We are proposing to describe the production process of
fluoridated waters in a hydrosocial context. This research is organized in four chapters. First, we start by introducing the reader to the theory of the hydrosocial cycle by presenting the literature on the matter. Next, we put into
context the practice of water fluoridation by first presenting the current state of affairs in
regards to water fluoration programs across the world, and second by presenting the
technical aspects of water fluoridation. After the reader has been presented with the
general themes covered by the subject of water fluoridation, we propose to rebuild a
hydrosocial of fluoridation. This story allows us to bring forward the hydrosocial relations
from which stems the production process of fluoridated waters. The hydrosocial history of
fluoridation includes a contemporary historical phase in which we introduce some key
ideas about the opposition to artificial water fluoration. Furthermore, we try to illustrate
some of the hydrosocial principles of fluoridation that are representative of the
contemporary narratives by doing an iconographic analysis of images on the subject of
fluoridation. Finally, we discuss about the implications of the hydrosocial cycle theory on
the study of the fluoridation problem.
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Uso do flúor em saúde pública sob o olhar dos delegados à 13ª Conferência Nacional de Saúde / Use of fluoride in public health from the perspective of the delegates to the 13th National Health ConferenceLucena, Regina Glaucia Ribeiro de 25 October 2010 (has links)
Introdução Sendo a cárie dentária um grave problema de saúde pública para a maioria dos indivíduos que moram em países do hemisfério Sul e para as populações com baixo status socioeconômico dos países de capitalismo desenvolvido, advoga-se o uso do flúor em saúde pública, como medida preventiva. Objetivo Descrever as percepções e opiniões dos delegados à 13ª Conferência Nacional de Saúde sobre o uso do flúor em saúde pública, com foco na fluoretação das águas de abastecimento público. Método - Realizou-se pesquisa exploratória, descritiva, com abordagem qualitativa, utilizando-se como técnica de processamento de depoimentos o Discurso do Sujeito Coletivo (DSC). Ao todo, foram 310 respondentes. Os dados foram coletados por meio de questionários semiestruturados e analisados por meio da análise do discurso. Resultados Constatou-se desinformação dos delegados no tocante a vários aspectos do uso do flúor em saúde pública e os mesmos sentem necessidade de meios de divulgação efetivos sobre a água para consumo e sobre os níveis de flúor da água. Considerações Finais - Ideias equivocadas ou lacunas de conhecimento acerca de vários aspectos do uso do flúor em saúde pública revelam a necessidade de se melhorar o nível de informação da sociedade sobre questões relativas à fluoretação. O desconhecimento dos delegados, aliado aos dados encontrados na literatura sobre as deficiências no monitoramento e controle dos níveis de flúor na água são indicativos da necessidade de se reavaliar o papel dos atores sociais e os mecanismos utilizados no controle social / Introducion - As tooth decay a serious public health problem for most residents of countries of the southern hemisphere and for populations of low socioeconomic status in developed capitalist countries, the use of fluoride in public health is advocated as a preventive measure. Objective - To describe the perceptions of the delegates to the 13th National Health Conference on the use of fluorides in public health, focusing on the fluoridation of public water supplies. Method - An exploratory and descriptive research was performed with a qualitative approach and utilizing as the processing technique of statements the Discourse of the Collective Subject (DCS). A total of 310 participants responded. The data was collected using semi-structured questionnaires and analysed by the discourse analysis method. Results - Misinformation of the delegates concerning several of the use of fluoride in public health and the need of these delegates for effective means of disseminating information on water suitable for consumption and the levels of fluoride in water was found. Final Considerations - Erroneous ideas and knowledge gaps regarding the various aspects of the use of fluoride in public health underscore the need to improve societys level of understanding of questions relating to water fluoridation. The lack of knowledge of delegates, together with the data available in the literature on the defective monitoring and control of fluoride levels in the water, indicates the need to further evaluate the role of the social actors and the mechanisms used in the societal control
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Uso do flúor em saúde pública sob o olhar dos delegados à 13ª Conferência Nacional de Saúde / Use of fluoride in public health from the perspective of the delegates to the 13th National Health ConferenceRegina Glaucia Ribeiro de Lucena 25 October 2010 (has links)
Introdução Sendo a cárie dentária um grave problema de saúde pública para a maioria dos indivíduos que moram em países do hemisfério Sul e para as populações com baixo status socioeconômico dos países de capitalismo desenvolvido, advoga-se o uso do flúor em saúde pública, como medida preventiva. Objetivo Descrever as percepções e opiniões dos delegados à 13ª Conferência Nacional de Saúde sobre o uso do flúor em saúde pública, com foco na fluoretação das águas de abastecimento público. Método - Realizou-se pesquisa exploratória, descritiva, com abordagem qualitativa, utilizando-se como técnica de processamento de depoimentos o Discurso do Sujeito Coletivo (DSC). Ao todo, foram 310 respondentes. Os dados foram coletados por meio de questionários semiestruturados e analisados por meio da análise do discurso. Resultados Constatou-se desinformação dos delegados no tocante a vários aspectos do uso do flúor em saúde pública e os mesmos sentem necessidade de meios de divulgação efetivos sobre a água para consumo e sobre os níveis de flúor da água. Considerações Finais - Ideias equivocadas ou lacunas de conhecimento acerca de vários aspectos do uso do flúor em saúde pública revelam a necessidade de se melhorar o nível de informação da sociedade sobre questões relativas à fluoretação. O desconhecimento dos delegados, aliado aos dados encontrados na literatura sobre as deficiências no monitoramento e controle dos níveis de flúor na água são indicativos da necessidade de se reavaliar o papel dos atores sociais e os mecanismos utilizados no controle social / Introducion - As tooth decay a serious public health problem for most residents of countries of the southern hemisphere and for populations of low socioeconomic status in developed capitalist countries, the use of fluoride in public health is advocated as a preventive measure. Objective - To describe the perceptions of the delegates to the 13th National Health Conference on the use of fluorides in public health, focusing on the fluoridation of public water supplies. Method - An exploratory and descriptive research was performed with a qualitative approach and utilizing as the processing technique of statements the Discourse of the Collective Subject (DCS). A total of 310 participants responded. The data was collected using semi-structured questionnaires and analysed by the discourse analysis method. Results - Misinformation of the delegates concerning several of the use of fluoride in public health and the need of these delegates for effective means of disseminating information on water suitable for consumption and the levels of fluoride in water was found. Final Considerations - Erroneous ideas and knowledge gaps regarding the various aspects of the use of fluoride in public health underscore the need to improve societys level of understanding of questions relating to water fluoridation. The lack of knowledge of delegates, together with the data available in the literature on the defective monitoring and control of fluoride levels in the water, indicates the need to further evaluate the role of the social actors and the mechanisms used in the societal control
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Avaliação da desfluoretação de águas com coagulante de Moringa oleifera Lam e do processo de separação por membranasConceição, Vinicius Masquetti da 04 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O consumo de águas com alto teor de flúor pode resultar em fluorose dental ou esquelética, além de outros malefícios para a saúde pública. Neste sentido, o presente trabalho avaliou o processo de redução de flúor contido em excesso em água sintética e subterrânea fluorada a partir do processo de coagulação/floculação/sedimentação (C/F/S) com extrato aquoso de Moringa oleifera Lam e, do processo combinado com filtração por membranas. Os ensaios de C/F/S foram realizados em equipamento “jar test”, sendo a Moringa, utilizada na forma de extrato aquoso em diferentes concentrações. As amostras de água sintética e subterrânea foram fluoradas com fluoreto de sódio (NaF) nas concentrações de 3,0; 5,0; 7,5 e 10,0 mg F-/L e, variando-se o pH entre 3, 7 e 9. Os ensaios combinados com membranas de microfiltração e ultrafiltração, utilizando-se pressões de 1 e 2 bar, consistiram em submeter amostras de água sintética fluorada na concentração inicial de 5,0 mg F-/L, concentração de Moringa de 5 g/L e, pH7 ao processo de C/F/S, seguido da passagem pelo módulo de micro-ultrafiltração. O monitoramento do sistema de tratamento proposto, foi verificado por meio das análises de cor aparente, turbidez, pH, condutividade e flúor, antes e após os ensaios. Os resultados demonstraram bons valores de eficiência para o tratamento proposto de C/F/S, sendo que, para a concentração inicial de flúor de 3,0 mg F-/L todos os residuais de flúor tanto para a água sintética como para a água subterrânea fluorada, ficaram abaixo do valor máximo estabelecido pela Portaria nº 2.914/2011 do Ministério da Saúde que estabelece o limite de 1,5 mg F-/L. Os demais residuais provenientes das concentrações de 5,0; 7,5 e 10,0 mg F-/L, ficaram ligeiramente acima da legislação. Os valores de pH final ficaram dentro da faixa de neutralidade. Em relação aos parâmetros cor, turbidez e condutividade final, houve um ligeiro aumento dos valores, sendo indicado uma posterior etapa de pós-tratamento, como a adoção de filtração. Para o processo combinado, obteve-se bons resultados de redução de flúor, cor e turbidez da ordem de 83,0 %, 96,0 % e 98,0 %, respectivamente, para a membrana de 5 kDa utilizando pressão de 2 bar. De modo geral, os processos de tratamento propostos utilizando extrato de sementes de Moringa oleifera Lam, demonstraram-se como uma boa alternativa para a redução do excesso de flúor em águas, tendo-se em vista a utilização de um agente coagulante natural, biodegradável e responsável pela geração de um menor volume de lodo, diferentemente do que é observado com a utilização de coagulantes químicos. / The consumption of water with high fluoride levels may result in dental or skeletal fluorosis, and other hazards to public health. In this sense, the present study evaluated the process of reducing excess fluoride contained in fluoridated synthetic water and groundwater from the coagulation/ flocculation/sedimentation (C/F/S) with aqueous extract of Moringa oleifera Lam, and the process combined with membrane filtration. Assays C/F/S were performed in "jar test", and Moringa, used in the aqueous extract at different concentrations. Water samples were fluorinated and ground synthetic sodium fluoride (NaF) at concentrations of 3.0, 5.0, 7.5 and 10.0 mg F-/L, varying the pH between 3, 7 and 9. Tests combined with microfiltration and ultrafiltration membranes, using pressures of 1 bar and 2, consisting in subjecting samples of fluorinated synthetic water initial concentration of 5.0 mg F-/L, Moringa concentration of 5 g/L and , pH7 to process C/F/S, followed by passage through micro-ultrafiltration module. The monitoring system proposed treatment was assessed through analyzes of apparent color, turbidity, pH, conductivity and fluoride before and after the tests. The results showed good efficiency values proposed for the treatment of C/F/S, and so the initial concentration of 3.0 mg/L of fluoride all residual to both the synthetic water as the water Fluorinated underground, were below the maximum established by Ordinance nº 2.914/2011 the Ministry of Health establishing the limit of 1.5 mg F-/L. The remaining residual concentration of from 5.0: 7.5 and 10.0 mg F-/L, were slightly above the law. The final pH values were within the range of neutrality. The parameters color, turbidity and conductivity end there was a slight increase in values, and a subsequent step indicated post-treatment such as the adoption of filtration. To the combined process, good results were obtained reduction fluorine, color and turbidity of the order of 83.0%, 96.0% and 98.0% respectively for the 5 kDa membrane using pressure of 2 bar. Generally, treatment processes proposed using seed extract Moringa oleifera Lam, proved to be a good alternative to the reduction of excess of fluorine in water, with a view to the use of a coagulating agent natural, biodegradable and the generation of smaller volumes of sludge, unlike what is observed with the use of chemical coagulants.
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Avaliação da desfluoretação de águas com coagulante de Moringa oleifera Lam e do processo de separação por membranasConceição, Vinicius Masquetti da 04 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O consumo de águas com alto teor de flúor pode resultar em fluorose dental ou esquelética, além de outros malefícios para a saúde pública. Neste sentido, o presente trabalho avaliou o processo de redução de flúor contido em excesso em água sintética e subterrânea fluorada a partir do processo de coagulação/floculação/sedimentação (C/F/S) com extrato aquoso de Moringa oleifera Lam e, do processo combinado com filtração por membranas. Os ensaios de C/F/S foram realizados em equipamento “jar test”, sendo a Moringa, utilizada na forma de extrato aquoso em diferentes concentrações. As amostras de água sintética e subterrânea foram fluoradas com fluoreto de sódio (NaF) nas concentrações de 3,0; 5,0; 7,5 e 10,0 mg F-/L e, variando-se o pH entre 3, 7 e 9. Os ensaios combinados com membranas de microfiltração e ultrafiltração, utilizando-se pressões de 1 e 2 bar, consistiram em submeter amostras de água sintética fluorada na concentração inicial de 5,0 mg F-/L, concentração de Moringa de 5 g/L e, pH7 ao processo de C/F/S, seguido da passagem pelo módulo de micro-ultrafiltração. O monitoramento do sistema de tratamento proposto, foi verificado por meio das análises de cor aparente, turbidez, pH, condutividade e flúor, antes e após os ensaios. Os resultados demonstraram bons valores de eficiência para o tratamento proposto de C/F/S, sendo que, para a concentração inicial de flúor de 3,0 mg F-/L todos os residuais de flúor tanto para a água sintética como para a água subterrânea fluorada, ficaram abaixo do valor máximo estabelecido pela Portaria nº 2.914/2011 do Ministério da Saúde que estabelece o limite de 1,5 mg F-/L. Os demais residuais provenientes das concentrações de 5,0; 7,5 e 10,0 mg F-/L, ficaram ligeiramente acima da legislação. Os valores de pH final ficaram dentro da faixa de neutralidade. Em relação aos parâmetros cor, turbidez e condutividade final, houve um ligeiro aumento dos valores, sendo indicado uma posterior etapa de pós-tratamento, como a adoção de filtração. Para o processo combinado, obteve-se bons resultados de redução de flúor, cor e turbidez da ordem de 83,0 %, 96,0 % e 98,0 %, respectivamente, para a membrana de 5 kDa utilizando pressão de 2 bar. De modo geral, os processos de tratamento propostos utilizando extrato de sementes de Moringa oleifera Lam, demonstraram-se como uma boa alternativa para a redução do excesso de flúor em águas, tendo-se em vista a utilização de um agente coagulante natural, biodegradável e responsável pela geração de um menor volume de lodo, diferentemente do que é observado com a utilização de coagulantes químicos. / The consumption of water with high fluoride levels may result in dental or skeletal fluorosis, and other hazards to public health. In this sense, the present study evaluated the process of reducing excess fluoride contained in fluoridated synthetic water and groundwater from the coagulation/ flocculation/sedimentation (C/F/S) with aqueous extract of Moringa oleifera Lam, and the process combined with membrane filtration. Assays C/F/S were performed in "jar test", and Moringa, used in the aqueous extract at different concentrations. Water samples were fluorinated and ground synthetic sodium fluoride (NaF) at concentrations of 3.0, 5.0, 7.5 and 10.0 mg F-/L, varying the pH between 3, 7 and 9. Tests combined with microfiltration and ultrafiltration membranes, using pressures of 1 bar and 2, consisting in subjecting samples of fluorinated synthetic water initial concentration of 5.0 mg F-/L, Moringa concentration of 5 g/L and , pH7 to process C/F/S, followed by passage through micro-ultrafiltration module. The monitoring system proposed treatment was assessed through analyzes of apparent color, turbidity, pH, conductivity and fluoride before and after the tests. The results showed good efficiency values proposed for the treatment of C/F/S, and so the initial concentration of 3.0 mg/L of fluoride all residual to both the synthetic water as the water Fluorinated underground, were below the maximum established by Ordinance nº 2.914/2011 the Ministry of Health establishing the limit of 1.5 mg F-/L. The remaining residual concentration of from 5.0: 7.5 and 10.0 mg F-/L, were slightly above the law. The final pH values were within the range of neutrality. The parameters color, turbidity and conductivity end there was a slight increase in values, and a subsequent step indicated post-treatment such as the adoption of filtration. To the combined process, good results were obtained reduction fluorine, color and turbidity of the order of 83.0%, 96.0% and 98.0% respectively for the 5 kDa membrane using pressure of 2 bar. Generally, treatment processes proposed using seed extract Moringa oleifera Lam, proved to be a good alternative to the reduction of excess of fluorine in water, with a view to the use of a coagulating agent natural, biodegradable and the generation of smaller volumes of sludge, unlike what is observed with the use of chemical coagulants.
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Fluor em agua e prevalencia de fluorose no estado de São Paulo / Fluorine in water and fluorosis prevalence in state of São Paulo, Southern BrazilKomati, Sergio Hideki 15 August 2008 (has links)
Orientador: Bernardino Ribeiro de Figueiredo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-11T21:52:30Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: O conteúdo do presente trabalho encontra-se distribuído em dois capítulos na forma de artigos científicos constituindo duas partes distintas. Na primeira parte constam os resultados obtidos em levantamento da informação disponível sobre fluorose dentária e ocorrência de flúor em água subterrânea no Estado de São Paulo. Consistiu de um estudo descritivo simples, com fontes de dados documentais e resultantes de busca nos portais da Biblioteca Virtual de Saúde-BIREME, banco de teses e portal de periódicos da CAPES e Google, utilizando-se como descritores: flúor, fluorose, água subterrânea e São Paulo, os quais foram cruzados para obtenção de resultados. Utilizou-se também dados do Ministério da Saúde-Brasil, Companhia de Tecnologia de Saneamento Ambiental (CETESB), Agência Nacional das Águas (ANA) e do Departamento de Água e Esgoto do Estado de São Paulo (DAEE). Foram identificados os municípios onde se localizam poços com teores elevados de fluoreto bem como os municípios onde foram relatados casos de fluorose dentária moderada e severa como, por exemplo, Amparo, Bebedouro, Campinas, Itapirapuã Paulista, entre outros. As ocorrências de poços com excesso de fluoreto, com concentrações capazes de acarretar fluorose dentária e óssea, e municípios que apresentaram casos de fluorose dental moderada e severa, distribuem-se por todo território paulista sobre seus principais aqüíferos. Em geral, observou-se que os municípios que não utilizam fluoretação da água de abastecimento não apresentam casos de fluorose, com exceção de Itapirapuã Paulista, localizado em região próxima a ocorrências e jazidas de fluorita. A segunda parte deste estudo consistiu de uma avaliação da qualidade das águas com respeito ao flúor que serviu de base para discutir as informações sobre a prevalência de fluorose em Amparo (SP). Realizaram-se três campanhas para coleta de águas superficiais, subterrâneas e tratada, e duas de fontes naturais e água engarrafada. Em cada ponto foram tomados os parâmetros físicoquímicos in situ e coletadas alíquotas de água filtrada para análise em cromatógrafo de íons. Constatou-se que as águas superficiais apresentaram concentrações de flúor variando entre 0,09 e 0,14 mg L-1. A água tratada apresentou, em 29,4% das amostras, concentração de flúor dentro do intervalo considerado ótimo para o Estado de São Paulo (0,6 a 0,8 mg L-1), variando entre 0,48 e 1,4 mg L-1. Os poços, fontes naturais e água engarrafada apresentaram baixas concentrações de fluoreto em 100% das amostras, no intervalo de <0,01 a 0,58 mg L-1. As informações disponíveis sobre a prevalência de fluorose dental em Amparo revelam que em escolares de 12 anos de idade obteve-se em 2002 um índice de 7,4% evoluindo em 2004 para 34% principalmente dos graus muito leve e leve. Verificou-se, não obstante, que parte da população do município de Amparo está sujeita ao consumo de água subfluoretada (poços, fontes e água engarrafada) e parte está ocasionalmente exposta ao consumo de água com excesso de flúor (água tratada). Embora a prevalência de fluorose tenha aumentado em Amparo nos últimos anos, constata-se também que parte da população está sem o efeito protetor da fluoretação contra a cárie dentária ensejando monitoramento periódico da qualidade das águas e um maior controle por parte da vigilância sanitária. / Abstract: This work presents two parts in the form of scientific articles. In the first part are the results obtained from the available information on dental fluorosis and on the occurrence of fluorine in groundwater in the State of Sao Paulo, Brazil. This part consisted of a simple descriptive study using documentary data such as technical reports and data bases available at the Virtual Library of Health-BIREME, theses and journals at CAPES web site and Google, using descriptors such as fluorine, fluorosis, groundwater and São Paulo. In addition, some information from the Ministry of Health-Brazil, the Technology Environmental Sanitation Company (CETESB), National Water Agency (ANA) and the Department of Water and Sewerage of the State of Sao Paulo (DAEE) were used. Based on the collected information two groups of municipalities were identified: (i) municipalities where groundwater was found to contain high levels of fluoride e.g. Amparo, Araçatuba, Campinas, Sorocaba among others and, (ii) municipalities where moderate and severe fluorosis were indicated e.g. Amparo, Bebedouro, Campinas, Itapirapuã Paulista among others. Examples of wells with excess of fluoride in water, which can lead to dental and skeletal fluorosis and, municipalities with cases of moderate and severe dental fluorosis, are spread throughout Sao Paulo State on its major aquifers. In general, it was observed that municipalities where fluoride addition to drink water is not used cases of dental fluorosis are not found, except for Itapirapuã Paulista that is located near the region hosting occurrences and ore deposits of fluorite. The second part of this study consisted of water quality assessment with respect to fluoride in the Amparo Municipality, Brazil, aimed to highlight and to discuss the information on the prevalence of fluorosis in that area. Three sampling campaigns for collection of surface water, groundwater and treated water, and two campaigns for collection of natural springs and bottled water were carried out. At each point the physical and chemical water quality parameters were measured in the field and, aliquots of filtered water for chemical analysis in ionic chromatography were collected. It was found that fluoride concentrations in surface water ranged from 0.09 and to 0.14 mg L-1. About 29 % of the samples of treated water showed fluoride concentrations in the range considered optimal for the state of Sao Paulo (0.6 to 0.8 mg L-1), between 0.48 and 1.4 mg L-1. Groundwater, spring water and bottled water showed low concentrations of fluoride in 100% of the samples ranging from <0.01 to 0.58 mg L-1. The available information on the prevalence of dental fluorosis in Amparo shows that among 12 years old schoolchildren dental fluorosis increased from 7.4 % in 2002 to 34 % in 2004 mainly in the very light and mild levels. The present study, however, indicates that part of the population of the Amparo municipality is subject to consumption of low fluoride water from wells, fountains and bottled water and, part of population is occasionally exposed to consumption of water with excess of fluoride (treated water). Although the prevalence of fluorosis in Amparo has increased in recent years, it was also noted that part of the population remains without the fluoride protection effect against dental caries which leads to the conclusion that regular monitoring of water quality and an active sanitary surveillance are necessary. / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências
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Verband tussen die fluoriedinhoud van drinkwater en die voorkoms van tandfluorose in geselekteerde gebiede in Suid-Afrika : 'n medies-geografiese studieZietsman, Susanna 25 August 2009 (has links)
Text in Afrikaans / Die tydruimtelike variasie in die fluoriedinhoud vannatuurlike drinkwater en in die voorkoms van tandfluorose, die verband tussen hierdie veranderlikes asook hulle kovariasie is op 'n hoe
resolusievlak in geselekteerde endemiese gebiede ondersoek. Die drie studiegebiede verskil grootliks van mekaar wat sommige fisies- en menslik-geografiese kenmerke betref, maar ondergrondse water was oral die belangrikste bron van drinkwater. Ioonspesifieke analise en laboratoriumtegnieke is gebruik om die fluoriedinhoud van die
drinkwater uit 517 bronne te bepaal. Die tande van 3 068 kinders is klinies en fotografies ondersoek. Die erkende Tooth Fluorosis Index en die indeks van Dean is gebruik om die voorkoms van fluorose te beskryf. Grafiese tegnieke, beskrywende statistieke en nieparametriese analise van variansietoetse is gebruik om die voorkoms en tydruimtelike variasiepatrone van die
sleutelveranderlikes in elke studiegebied, asook die verskillende ruimtelike eenhede binne die studiegebiede, te beskryf. Die verband tussen die sleutelveranderlikes asook hul intra- en interareale
kovariasie is ontleed. Daar is gevind dat die fluoriedinhoud van die ondergrondse water in die Pilanesberg- en Hammanskraal-studiegebied relatief hoog tot hoog is en die in die Vrystaat-studiegebied relatief laag. Ruimtelike veranderlikheid met groot verskille oor klein afstande kenmerk die fluoriedinhoud van ondergrondse water ongeag die gesteentes waaruit dit onttrek word.
Middelwaardes bied ontoereikende beskrywings van die fluoriedgehalte van die drinkwater. Die skep van nuwe drinkwaterbronne veroorsaak langtermynvariasie in die fluoriedinhoud van die beskikbare drinkwater.
Fluoroseprevalensie in die studiegebiede bet van 62% tot 87% gewissel, met meer ernstige aantasting in die Pilanesberg- en Hammanskraal-gebied as in die Suid-Vrystaat. Beduidende
intra-areale ruimtelike variasie is 'n wesenlike kenmerk van die voorkoms van fluorose in al drie studiegebiede. In alle gevalle het die variasiepatroon in die fluoriedinhoud van die drinkwater die
in die voorkoms van fluorose slegs gedeeltelik verklaar. Sporadiese en/of periodieke kortstondige blootstelling aan hoe fluoriedkonsentrasies lei tot emstige aantasting ten spyte van die gereelde gebruik van water met 'n laefluoriedinhoud. Ligte fluorose ontwikkel geredelik in assosiasie met <0,5 mgF-/l en matige fluorose in assossiasie met 0,5-0,7 mgF-/l, die optimum konsentrasieinterval vir fluoridasie in Suid-Afrika. / The spatiotemporal variation in the fluoride content of natural drinking water and the occurrence
of dental fluorosis, the relation between these variables as well as their covariation were
investigated at a high resolution level in selected endemic areas. Groundwater was the most
important source of drinking water in all three study areas, but they differed markedly in respect
of some physical and human geographical characteristics.
Ion specific analysis and laboratory techniques were used to determine the fluoride content of
the water from 517 sources. The teeth of 3 068 children were examined clinically and
photographically. The fluorosis was scored according to the Tooth Fluorosis Index and Dean's
classification. Graphical techniques, descriptive statistics and nonparametric analysis of variance
were used to describe the occurrence and variation patterns of the key variables in the different
spatial units is each study area. The relation between the variables as well as their intra and interareal
covariation were analysed.
The fluoride content of the groundwater in the Pilanesberg and Hammanskraal areas was
relatively high to high; in the southern Free State it was relatively low. Spatial variability and
significant differences over small distances typify the fluoride content of the groundwater,
irrespective of the aquifer. Central statistics inadequately describe the fluoride quality of the
natural drinking water. The development of new water sources causes long term variation in the
fluoride content of the available drinking water.
Fluorosis prevalence varied form 62% to 87%, with more severe fluorosis in Pilanesberg and Hammanskraal than in the southern Free State. Significant intra-areal spatial variation is an
attribute of fluorosis in all three study areas. In all cases the variation pattern in the fluoride
content of the drinking water partly explained the spatial pattern in the occurrence of fluorosis.
Sporadic and/or periodic brief exposure to high fluoride concentrations leads to severe fluorosis
despite regul~ usage of water with a low fluoride content. Mild fluorosis readily develops in
association with <0,5 mgF-1~ and medium fluorosis in association with 0,5-0,7 mgF-/l, the
optimum concentration interval for fluoridation in South Africa. / Geography / D. Phil. (Geografie)
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Development of a small scale water treatment system for fluoride removal for rural areasDlamini, Thulani January 2015 (has links)
Submitted in fulfillment of the requirements for the degree of Master of Engineering in Chemical Engineering, Durban University of Technology. Durban. South Africa, 2015. / Several areas in the world such as the United States of America, Sri Lanka, China, Argentina, Canada, Tanzania, Kenya, South Africa and many others have a problem of high fluoride content in drinking water. Generally fluoride levels above 1.5 ppm in water may result in dental and skeletal fluorosis in humans depending on quantity consumed (Fan et al., 2003; Meenakshi, 2004). Remote rural areas where there are no water treatment facilities are more vulnerable to this problem.
Adsorbents such as activated alumina and FR-10 resin seem to have a potential for successful application in rural areas. These methods however require pre-treatment if the feed has high turbidity. A membrane based system called woven fabric microfiltration gravity filter (WFMFGF) developed by Durban University of Technology proved to be suitable for turbidity removal.
The main objective of this research was to develop a small water treatment system for fluoride removal. The small water treatment system developed in this study consists of WFMFGF for pre-treatment and an adsorption column. The WFMFGF is made up of a 40 L container packed with 15 immersed flat sheet membrane elements. The operation of the WFMFGF is in batch mode, driven by varying static head. The static head variation results in flow rate variation through the system. This in turn result in variation of contact time, velocity as well as pressure drop in the fluoride removal unit.
Specific objectives of the study were: (1) to establish the maximum and minimum flow rates through the WFMFGF system, the total run time before cleaning is required and the best cleaning method for this particular membrane system. (2) to evaluate and compare the performance of activated alumina and FR-10 resin on varying contact time, velocity and pressure drop on the fluoride removal unit. The adsorbents were also compared on adsorption capacity, cost and ease of operation.
The minimum and maximum flow rates through the WFMFGF were found to be 5 l/hr and 100 l/hr respectively. It was found that the system can be run for more than a month before requiring cleaning. The suitable cleaning method was found to be soaking the membranes in 0.0225 percent sodium hypochlorite solution overnight and brushing them using a plastic brush.
The comparison of the performance of FR-10 resin to activated alumina found that the adsorbents gave equal performance based on the given criteria. FR-10 resin had higher adsorption capacity, gave good quality treated water even with shorter contact time and operated at wider velocity range.
Activated alumina on the other hand had an advantage of lower costs, lower pressure drop and ease of use. According to Pontius (1990), the performance of activated alumina can be improved by intermittent operation. Point of use (POU) systems are generally operated intermittently. This improves the fluoride removal efficiency of activated alumina giving it more advantage over FR-10 resin. Based on this activated alumina was selected as the best adsorbent for the system.
After the adsorbent was selected, the adsorption column was designed. The column operation regime was 3.5 minutes minimum contact time and 1.17 to 7.8 m/hr velocity range. The activated alumina adsorption capacity was 1.53mg/g. The column had an inside diameter of 70 mm. It was packed with activated alumina to a bed height of 400 mm. The column inlet and outlet pipes were made of PVC with a standard pipe size of 20 mm outside diameter. A valve at the column inlet pipe allowed water to flow through the system.
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