Groundwater is a major and sometimes lone source of drinking water worldwide. The chemical composition of groundwater is a combined product of the composition of water that enters the aquifer and its reaction with various minerals present in the soil and rock mass, which alter the water composition with time and space. Some important factors influencing groundwater quality are (1) physiochemical characteristics o the rocks through which the water circulates; (2) geology of the location; (3) climate of the area; (4) role of microorganisms, which includes oxidative and reductive biodegradation of organic matter; (5)chemical, physical, and mineralogical characteristics of the overburden soils through which the rainwater percolates; and (6) human intrusion affecting the hydrological cycle and degradation in water quality through utilization of water for agricultural and industrial activities. By far the most serious naturally occurring groundwater-quality problem in India derives from high fluoride, arsenic and iron concentrations which are dissolved from the bedrocks by geochemical processes. Presence of excess fluoride in groundwater is identified as a naturally occurring health hazard by the World Health Organization (WHO). Prolonged ingestion of fluoride beyond certain permissible limit leads to ffluorosis, one of the common water-related diseases recognized by the WHO and the United Nations Children's Fund (UNICEF). Endemic fluorosis is now known to be global in scope, occurring on all continents and affecting many millions of people. According to estimates made in the early 1980s, around 260 million people in 30 countries worldwide were drinking water with more than 1 ppm of fluoride. The ultimate source of fluoride in water, soil or biosphere is associated with its distribution in rocks and its dispersion in groundwater. The three most important minerals of fluoride are fluorite (CaF2), cryolite (Na3AlF6) and fluorapatite (Ca5(PO4)3F); cryolite is a rare mineral where as by far the largest amount of fluorine in the earth's crust is in the form of fluorapatite (about 3.5% by weight of fluorine) which is processed almost exclusively for its phosphate content. Fluoride substitutes readily in hydroxyl positions in late-formed minerals in igneous rocks, and in primary minerals especially micas (such as biotites) and amphiboles (such as hornblende). The most important controlling factors influencing fluoride presence in groundwater include: distribution of easily weathered fluoride-bearing minerals, the accessibility of circulating water to these minerals, pH of the percolating water, calcium content of the leaching water, temperature of the percolating water and the soil, exchangeable ions in the percolating water, extent of fresh water exchange in an aquifer, evaporation and evapotranspiration, complexing of fluoride ions with other ions, presence of CO2 and other chemicals in draining water and residence time of the percolating water in soil. High fluoride levels are observed in the groundwater in 19 states of the country. Fluorite, apatite, rock phosphate, phosphorites, phosphatic nodules and topaz are major fluoride bearing minerals in India with varying levels of fluoride content. There are three major fluoride bearing areas in India :1) Gujarat-Rajasthan in the north-west and 2) Chandidongri-Raipur in central India 3) Tamil Nadu-Andhra Pradesh in the south; besides other areas in Karnataka, Bihar, Punjab and in the North-west Himalayas. The total mineral reserves of fluorite, rock phosphate and apatite in the country are estimated at 11.6, 71 and 2.82 million tonnes respectively. The distribution of areas with excess fluoride in groundwater concurs with that of fluorine-bearing minerals. Further high fluoride concentrations are observed from arid and semi arid regions of the country and the areas with advanced stage of groundwater development. An estimated 62 million people, including 6 million children suffer from fluorosis in India because of consuming fluoride-contaminated water. Endemic fluorosis is found to practically exist only in the villages due to lack of piped water supply. The Indian Drinking Water Standard specifies the desirable and permissible limits for fluoride in drinking water as 1.0 and 1.5ppm respectively. De-fluoridation of groundwater is the only alternative to prevent fluorosis in the absence of alternate water source especially for immediate and/or interim relief. De-fluoridation of drinking water in India is usually achieved by the Nalgonda technique or activated alumina process. The Nalgonda method involves addition of aluminum salts (aluminium sulphate and/or aluminium chloride), lime and bleaching powder to water, followed by rapid mixing, flocculation, sedimentation, filtration and disinfection. Only aluminum salt is responsible for removal of fluoride from water .Fluoride removal is achieved in a combination of complexation with polyhydroxy aluminium species and adsorption on polymeric alumino hydroxides (floc). Activated alumina(Al2O3) was proposed for de-fluoridation of water for domestic use in 1930’s and since then it has become one of the most advocated de-fluoridation methods. Activated alumina is a semi crystalline porous inorganic adsorbent and an excellent medium for fluoride removal. When the source water passes through the packed column of activated alumina, fluoride (and other components in the water) is removed via exchange reaction with surface hydroxides on alumina; this mechanism is generally called adsorption although ligand exchange is a more appropriate term for the highly specific surface reactions involved. The fluoride removal capacity of alumina is highly sensitive to pH, the optimum being about pH5.5-6. Significant reduction in fluoride removal by activated alumina is also observed in presence of sulfate and silicate ions. The column needs periodic regeneration once break point(where the effluent concentration is, for example, 2ppm at normal saturation) is reached. For regeneration, the medium is backwashed for 5-10 min and then subjected to two step regeneration with base (NaOH) followed by acid(H2SO4). A major cause for concern with the Nalgonda method is the possibility of formation of residual aluminum and soluble aluminum fluoride complexes in the treated water and a potential breach of the 0.2ppm Indian drinking water standard for aluminium. Concerns with the activated alumina filter method are that the process is pH dependent, with an optimum (pH) working range of 5-6. Further, the activated alumina column requires periodic recharge using caustic soda and acid solutions to rejuvenate the fluoride retention capacity of the column. After 3-4 regenerations the medium has to be replaced. If the pH is not readjusted to normal following the regeneration process, there is a possibility that the aluminum concentration in the treated water may exceed the 0.2ppm standard. Due to the aforementioned drawbacks of the currentde-fluoridation technologies in India that chiefly rely on aluminum based compounds, magnesia(magnesium oxide, MgO) is selected to develop an alternate sustainable de-fluoridation method. The potential of MgO for de-fluoridation has been examined owing to its very limited solubility(6.2mg/L), non-toxicity and excellent fluoride retention capacity. A review of the previous studies on fluoride removal using MgO reveals that the relevant information is essentially scattered. Though studies demonstrated the fluoride removing ability of MgO and brought into focus certain aspects of the fluoride removal mechanism and change in water quality upon MgO addition, vital issues necessary for efficient design and successful field implementation of the de-fluoridation processusing MgO were not addressed. The significant limitations in the earlier works include: influence of process variables(such as MgO dosage, initial fluoride concentration, contact time, temperature, initial solution pH, presence of co-ions and ionic strength) on fluoride retention characteristics (such as removal rate, equilibrium time, capacity) of MgO were not systematically determined, optimum operating parameters/conditions (such as MgO dosage, stirring and settling time) for effective de-fluoridation process applicable to a wide range of groundwater chemical composition and fluoride concentrations were not defined, mechanism of fluoride retention by MgO was not fully understood, issue of lowering the pH of MgO treated water within potable water limits was not comprehensively addressed, safe disposal methods of fluoride bearing sludge were not explored. Failure to address the above issues has impeded the adoption of the MgO treatment method for fluoride removal from water. Scope of the study Present study aims to develop a new sustainable de-fluoridation method, applicable to a wide range of groundwater chemical compositions and fluoride concentrations, based on co-precipitation/precipitation-sedimentation-filtration processes using light MgO. Efforts are made to implement the method at domestic level in a rural area with incidence of high fluoride concentration in groundwater and to understand the status and geochemistry of fluoride contamination in the area. The main objectives of the study include: To determine the fluoride retention characteristics of MgO viz.,rate, equilibrium time and capacity of fluoride retention. To examine the influence of process variables on fluoride retention characteristics of MgO and to determine the optimum operating parameters for effective de-fluoridation process. To understand the mechanism and rate limiting step of MgO de-fluoridation process. To propose methods and specifications to lower the pH of MgO treated water within permissible limits to ensure its potability. To design a simple to use, single-stage domestic de-fluoridation unit. To propose procedures for implementation of the new de-fluoridation method in field. To evaluate the efficiency of the new de-fluoridation method as a useful remedial measure in the fluoride affected areas. To understand the geochemical factors governing the quality of the fluoride rich groundwater and to ascertain the status and geochemistry of fluoride contamination in the area where felid implementation of de-fluoridation method is planned. To characterize the fluoride bearing sludge and propose methods for safe disposal and reuse of fluoride bearing sludge. Organization of the thesis Chapter1 presents an overview of the various aspects of excess fluoride presence in groundwater, remedial measures, and emphasizes the need for a new sustainable de-fluoridation method and defines the scope of present study. Chapter 2 performs a detailed investigation to determine the fluoride retention characteristics of MgO under the influence of various process variables at transient and equilibrium conditions using batch studies. The process variables that have been considered are, contact time, initial fluoride concentration, dosage of MgO, temperature, initial pH, presence of co-ions and ionic strength. Studies to determine the optimum operating parameters for efficient de-fluoridation and to understand some basics of reaction mechanisms involved are also part of this chapter. Chapter 3 examines the true nature of the reaction mechanism between fluoride ions and MgO in aqueous media and the rate-limiting step of the de-fluoridation process by investigating the hydration process of MgO and its influence/relation on fluoride removal. Chapter 4 addresses issues that will assist applying the MgO treatment method for fluoride removal in field such as 1)methods and specifications for lowering the pH of the MgO treated water within permissible limits, 2)design of a simple to use, single-stage de-fluoridation unit, and 3)characterization of the resultant fluoride bearing sludge. Chapter 5 performs a detailed investigation to evaluate the efficiency of the new de-fluoridation method in laboratory and field, and to understand the origin and the geochemicall mechanisms driving the groundwater fluorine enrichment in the area where field implementation of the de-fluoridation unit was planned. Chapter 6 explores an environmentally safe route for the disposal and re-use of fluoride bearing sludge in soil based building materials such as, stabilized soil blocks (produced by cement stabilization of densely compacted soil mass) which are alternative to burnt bricks. Chapter 7 summarizes the major results, observations and contributions from the study.

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.

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.

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 Komati_SergioHideki_M.pdf: 2629006 bytes, checksum: 2810d03559d246f7e6cf98ebb9a6ef8c (MD5) 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

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.

Aim: The aim of this project was to find the level of oral health literacy of parents of preschool age children regarding their child’s oral health. The primary objective was to improve the oral health status of preschoolers and to prevent early childhood caries. Methods: 117 participants (parents of preschoolers) completed a self-administered oral health literacy questionnaire. Data obtained from the study was analysed using a statistical package (SPSS). Firstly, descriptive analysis was undertaken generating tables and graphs of sociodemographic variables. Later, associations between oral health literacy and sociodemographic variables were identified and also relation between parents’ oral health literacy and their attitude towards water fluoridation in Christchurch was identified using bivariate and multivariate analysis. Psychometric analysis was generated to test validity and reliability of the oral health literacy questionnaire. Results: In the total sample, 38% of participants had poor oral health literacy regarding their child’s oral health. The results also indicated that there were associations present between parents’ oral health literacy and socio-demographic variables such as ethnicity, education and family income. Nearly half of the parents opted for water fluoridation in Christchurch. A strong association between parents’ oral health literacy and their attitude towards water fluoridation was identified. In the total sample, 40% of parents were not aware of need for first dental visit before the school age. Reliability was good for the developed oral health literacy instrument. Conclusions: This study of parents’ oral health literacy in Christchurch, New Zealand identified association of oral health literacy and socio-demographic variables which gives future guidance to improving oral health status of New Zealand children. The relation 6 between parents’ oral health literacy and their attitude towards water fluoridation was shown in this study. This result might be used in future water fluoridation surveys. Future studies are needed to examine health care provider’s perspective in improving parents’ oral health literacy and to tailor more effective public health interventions to improve parents’ oral health literacy.

Made available in DSpace on 2014-06-11T19:33:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-28Bitstream added on 2014-06-13T19:43:56Z : No. of bitstreams: 1 casotti_ca_dr_araca.pdf: 660013 bytes, checksum: c630d7bb4fdb85d40a30ec52f8e05ca2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A fluoretação da água de abastecimento público é reconhecida como uma das principais estratégias de saúde pública para prevenir a cárie dentária. A cidade de Baixo Guandu, localizada no Estado do Espírito Santo, Brasil, foi a primeira a implantar o método. Foi objetivo do presente estudo avaliar o impacto que a fluoretação artificial da água proporcionou à saúde bucal de indivíduos com idade de 5, 12, 15 a 19, 20 a 34, 35 a 44 e 45 a 56 anos, que sempre viveram e consumiram exclusivamente água da rede de abastecimento público dos municípios de Baixo Guandu onde a fluoretação ocorre há 52 anos e Itarana, onde o método foi implantado há 3 anos. A metodologia, os códigos e os critérios adotados foram os recomendados pela Organização Mundial da Saúde (OMS), com a inserção dos grupos etários de 20 a 34 e 45 a 56 anos. Inicialmente foram identificados os moradores permanentes das duas cidades, as quais foram examinados no domicílio, com auxílio de espelho bucal e sonda periodontal CPI. Previamente à realização do estudo, o examinador passou por uma oficina de calibração e treinamento para a padronização dos diagnósticos da cárie dentária, fluorose dentária, perda dentária e uso e necessidade de prótese, em indivíduos com grupos etários semelhantes aos do estudo. Para o cálculo da concordância kappa intra-examinador, 10% dos indivíduos foram reexaminados, sendo os resultados obtidos para a cárie dentária 0,95; fluorose dentária 0,91; perda dentária 1 e o uso e necessidade de prótese 1. No total foram examinados 1588 moradores sendo 1129 (71,1%) de Baixo Guandu e 459 (28,9%) de Itarana. Foram utilizados os testes estatísticos Qui-quadrado, Fisher, Mann Whitney e de proporções com nível de significância de 5%. As médias do ceod aos 5 anos e CPOD aos 12, 15 a 19, 20 a 34, 35 a 44 e 45 a 56 anos foram, respectivamente, em Baixo Guandu... / The water fluoridation in the public supply is recognized as one of the main public health strategies to prevent dental caries. Baixo Guandu-ES was the first city to introduce this method in Brazil. The objective of the present study was to evaluate the impact that the artificial fluoridation of the water brought to the oral health of subjects in the age of 5, 12, 15 to 19, 20 to 34,35 to 44 and 45 to 56 years, that have always lived and consumed exclusively the water from the public supply of the city of Baixo Guandu for 52 years and Itarana where the method was introduced 3 years ago. The methodology, the codes and criteria adopted were recommended by the World Health Organization (WHO), with the insertion of age groups of 20 to 34 and 45 to 56 years. Initially the identification of the permanent inhabitants of both cities, was realized and they were locally examined with the aid of plan oral mirrors number 5 and CPI periodontal probes. Previously to this study, the examiner went through a calibrator's workshop and training for the diagnosis of dental caries, dental fluorosis, tooth loss, the use and need of prosthesis with age groups similar to the ones in the study. In order to have the Kappa's intra-examiner calculated, 10% of the individuals were re-examined and the obtained result for dental caries was 0.95; for dental fluorosis 0.91; for dental loss, and for the use and need for prosthesis 1. A total of 1588 inhabitants were examined, of those 1129 (71.1%) of Baixo Guandu and 459 (29.9%) of Itarana. The Chi-square, Fisher's, Mann-Whitney's and the Proportions tests with level of significance of 5% were used to verify the significant statistic of the results. The mean dmft for 5 year old subjects and DMFT for 12, 15 to 19, 20 to 34, 35 to 44 and 45 to 56 subjects were respectively in Baixo Guandu 2.32; 1,55; 3.48; 7.69; 13,85 and 16.49 and ...(Complete abstract, click electronic address below)

Orientador: Nemre Adas Saliba / Banca: Edgard Michel Crosato / Banca: Beatriz Unfer / Banca: Rogério Moreira Arcieri / Banca: Renato Herman Sundfeld / Resumo: A fluoretação da água de abastecimento público é reconhecida como uma das principais estratégias de saúde pública para prevenir a cárie dentária. A cidade de Baixo Guandu, localizada no Estado do Espírito Santo, Brasil, foi a primeira a implantar o método. Foi objetivo do presente estudo avaliar o impacto que a fluoretação artificial da água proporcionou à saúde bucal de indivíduos com idade de 5, 12, 15 a 19, 20 a 34, 35 a 44 e 45 a 56 anos, que sempre viveram e consumiram exclusivamente água da rede de abastecimento público dos municípios de Baixo Guandu onde a fluoretação ocorre há 52 anos e Itarana, onde o método foi implantado há 3 anos. A metodologia, os códigos e os critérios adotados foram os recomendados pela Organização Mundial da Saúde (OMS), com a inserção dos grupos etários de 20 a 34 e 45 a 56 anos. Inicialmente foram identificados os moradores permanentes das duas cidades, as quais foram examinados no domicílio, com auxílio de espelho bucal e sonda periodontal CPI. Previamente à realização do estudo, o examinador passou por uma oficina de calibração e treinamento para a padronização dos diagnósticos da cárie dentária, fluorose dentária, perda dentária e uso e necessidade de prótese, em indivíduos com grupos etários semelhantes aos do estudo. Para o cálculo da concordância kappa intra-examinador, 10% dos indivíduos foram reexaminados, sendo os resultados obtidos para a cárie dentária 0,95; fluorose dentária 0,91; perda dentária 1 e o uso e necessidade de prótese 1. No total foram examinados 1588 moradores sendo 1129 (71,1%) de Baixo Guandu e 459 (28,9%) de Itarana. Foram utilizados os testes estatísticos Qui-quadrado, Fisher, Mann Whitney e de proporções com nível de significância de 5%. As médias do ceod aos 5 anos e CPOD aos 12, 15 a 19, 20 a 34, 35 a 44 e 45 a 56 anos foram, respectivamente, em Baixo Guandu ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The water fluoridation in the public supply is recognized as one of the main public health strategies to prevent dental caries. Baixo Guandu-ES was the first city to introduce this method in Brazil. The objective of the present study was to evaluate the impact that the artificial fluoridation of the water brought to the oral health of subjects in the age of 5, 12, 15 to 19, 20 to 34,35 to 44 and 45 to 56 years, that have always lived and consumed exclusively the water from the public supply of the city of Baixo Guandu for 52 years and Itarana where the method was introduced 3 years ago. The methodology, the codes and criteria adopted were recommended by the World Health Organization (WHO), with the insertion of age groups of 20 to 34 and 45 to 56 years. Initially the identification of the permanent inhabitants of both cities, was realized and they were locally examined with the aid of plan oral mirrors number 5 and CPI periodontal probes. Previously to this study, the examiner went through a calibrator's workshop and training for the diagnosis of dental caries, dental fluorosis, tooth loss, the use and need of prosthesis with age groups similar to the ones in the study. In order to have the Kappa's intra-examiner calculated, 10% of the individuals were re-examined and the obtained result for dental caries was 0.95; for dental fluorosis 0.91; for dental loss, and for the use and need for prosthesis 1. A total of 1588 inhabitants were examined, of those 1129 (71.1%) of Baixo Guandu and 459 (29.9%) of Itarana. The Chi-square, Fisher's, Mann-Whitney's and the Proportions tests with level of significance of 5% were used to verify the significant statistic of the results. The mean dmft for 5 year old subjects and DMFT for 12, 15 to 19, 20 to 34, 35 to 44 and 45 to 56 subjects were respectively in Baixo Guandu 2.32; 1,55; 3.48; 7.69; 13,85 and 16.49 and ...(Complete abstract, click electronic address below) / Doutor

Vibrio infections remain a serious threat to public health. In the last decade, Vibrio disease outbreaks have created a painful awareness of the personal, economic, societal, and public health costs associated with the impact of contaminated water in the aquatic milieu. This study was therefore designed to assess the prevalence of Vibrio pathogens in the final effluents of wastewater treatment plants (WWTPs) in the Eastern Cape Province, as well as their abilities to survive the treatment processes of the activated sludge system either as free cells or as plankton-associated entities in relation to the physicochemical qualities of the effluents. Three wastewater treatment facilities were selected to represent typical urban, sub-urban and rural communities, and samples were collected monthly from August 2007 to July 2008 from the final effluent, discharge point, 500 meter upstream and downstream of the discharge points and analysed for physicochemical parameters, Vibrio pathogens prevalence and their antibiogram characteristics using both culture based and molecular techniques. Physicochemical parameters measured include pH, temperature, electrical conductivity, salinity, turbidity, total dissolved solid (TDS), dissolved oxygen (DO), chemical oxygen demand (COD), nitrate, nitrite and orthophosphate levels. Unacceptably high levels of the assayed parameters were observed in many cases for COD (<10 - 1180 mg/l), nitrate (0.08 - 13.14 mg NO3- as N/l), nitrite (0.06 - 6.78 mg NO2- as N/l), orthophosphate (0.07-4.81 mg PO43- as P/l), DO (1.24 - 11.22 mg/l) and turbidity (2.04 -159.06 NTU). Temperature, COD and nitrite varied significantly with season (P < 0.05), while pH, EC, salinity, TDS, COD, and nitrate all varied significantly with sampling site (P < 0.01; P < 0.05). In the rural wastewater treatment facility, free-living Vibrio densities varied from 0 to 3.45 × 101 cfu ml-1, while the plankton-associated Vibrio densities vary with plankton sizes as follows: 180 μm (0 – 4.50 × 103 cfu ml-1); 60 μm (0 – 4.86 × 103 cfu ml-1); 20 μm (0 – 1.9 × 105 cfu ml-1). The seasonal variations in the Vibrio densities in the 180 and 60 μm plankton size samples were significant (P < 0.05), while the 20 μm plankton size and free-living vibrios densities were not. Molecular confirmation of the presumptive vibrios isolates revealed V. fluvialis (36.5 percent), as the predominant species, followed by V. vulnificus (34.6 percent), and V. parahaemolyticus (23.1 percent), and V. metschnikovii (5.8 percent) (detected using only API 20 NE), suggesting high incidence of pathogenic Vibrio species in the final effluent of the wastewater facility. Correlation analysis suggested that the concentration of Vibrio species correlated negatively with salinity and temperature (P < 0.001 and P < 0.002 respectively) as well as with pH and turbidity (P < 0.001), in the final effluent. Population density of total Vibrio ranged from 2.1 × 101 to 4.36 × 104 cfu ml-1 and from 2.80 ×101 to 1.80 × 105 cfu ml-1 for the sub-urban and urban communities treatment facilities respectively. Vibrio species associated with 180 μm, 60 μm, and 20 μm plankton sizes, were observed at densities of 0 - 1.36 × 103 cfu ml-1, 0 - 8.40 × 102 cfu ml-1 and 0 - 6.80 × 102 cfu ml-1 respectively at the sub-urban community‘s WWTP. In the urban community, counts of culturable vibrios ranged from 0 - 2.80 × 102 cfu ml-1 (180 μm); 0 - 6.60 × 102 cfu ml-1 (60 μm) and 0 -1.80 × 103 cfu ml-1 (20 μm). Abundance of free-living Vibrio species varied between 0 and the orders of 102 and 103 cfu ml-1 in the sub-urban and urban communities WWTPs respectively. Molecular confirmation of the presumptive vibrios isolates revealed the presence of V. fluvialis (41.38 percent), V. vulnificus (34.48 percent), and V. parahaemolyticus (24.14 percent) in the sub-urban community effluents. In the urban community V. fluvialis (40 percent), V. vulnificus (36 percent), and V. parahaemolyticus (24 percent) were detected. There was no significant correlation between Vibrio abundance and season, either as free-living or plankton-associated entities, while Vibrio species abundance correlated positively with temperature (r = 0.565; P < 0.01), salinity and dissolved oxygen (P < 0.05). Turbidity and pH showed significant seasonal variation (P < 0.05) in both locations. The Vibrio strains showed the typical multi-antibiotic-resistance of an SXT element. They were resistant to sulfamethoxazole (Sul), trimethoprim (Tmp), cotrimoxazole (Cot), chloramphenicol (Chl) and streptomycin (Str), as well as other antibiotics such as ampicillin (Amp), penicillin (Pen), erythromycin (Ery), tetracycline (Tet), nalidixic acid (Nal), and gentamicin (Gen). The antibiotic resistance genes detected includes dfr18 and dfrA1 for trimethoprim; tetA, strB, floR, sul2 blaP1, for tetracycline, streptomycin, chloramphenicol, sulfamethoxazole and β-lactams respectively. A number of these genes were only recently described from clinical isolates, demonstrating genetic exchange between clinical and environmental Vibrio species. This study revealed that there was an adverse impact on the physicochemical characteristics of the receiving watershed as a result of the discharge of inadequately treated effluents from the wastewater treatment facilities. The occurrence of Vibrio species as plankton-associated entities confirms the role of plankton as potential reservoir for this pathogen. Also the treated final effluents are reservoirs of various antibiotics resistance genes. This could pose significant health and environmental risk to the biotic component of the environment including communities that rely on the receiving water for domestic purposes and may also affect the health status of the aquatic milieu in the receiving water. There is need for consistent monitoring programme by appropriate regulatory agencies to ensure compliance of the wastewater treatment facilities to regulatory effluent quality standards.

MENVSC / Department of Ecology and Resource Management / See the attached abstract below