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Chumbo na água de consumo de Ribeirão Preto (SP): fatores químicos, físicos e possíveis correlações com a contaminação de crianças; Lead in drinking water from Ribeirão Preto (SP): chemical and physical factors and possible correlations with children contamination

Grigoletto, Tahuana Luiza Bim
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 21/03/2011 PT
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66.47%
A intoxicação por chumbo tem conseqüências devastadoras para o ser humano, principalmente para crianças. Em Ribeirão Preto foram detectadas crianças com níveis de chumbo no dente tão elevados quanto de crianças com conhecida contaminação na cidade de Bauru (SP). Diante disso, este trabalho teve como objetivos investigar fatores físicos e químicos que possam elevar a concentração de chumbo na água de consumo, e avaliar a possível correlação entre a contaminação por chumbo nas crianças com a água de suas residências. O estudo da capacidade de corrosão da água utilizando um pedaço de cano a base de chumbo mostrou que ao diminuir o pH de 6,40 para 5,94 a lixiviação de chumbo aumentou 3 vezes, enquanto o aumento de 6,40 para 7,06 diminuiu a lixiviação em 20%, após 8 horas de experimento. Não foi observada influência na capacidade de corrosão em testes de 48 horas quando aumentou-se a dureza da água. Foram coletadas amostras (1L) de água das 40 casas estudadas, sendo as primeiras alíquotas coletadas após pelo menos 6 horas de repouso nos encanamentos. Amostras de água recém tratada de 11 postos de abastecimento de Ribeirão Preto serviram como controle. A faixa de condutividade da água das casas foi bastante ampla (50...

Contaminantes emergentes em água tratada e seus mananciais : sazonalidade, remoção e atividade estrogênica; Emerging contaminants in source and drinking water : seasonalities, removal and estrogenic activity

Cassiana Carolina Montagner Raimundo
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/09/2011 PT
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O objetivo deste trabalho foi avaliar, através de um perfil anual, a qualidade dos mananciais e da água tratada de Campinas (SP) em relação à presença de cafeína, estrona, 17b-estradiol, estriol, progesterona, testosterona, 17a-etinilestradiol, mestranol, levonorgestrel, dietilestilbestrol, triclosan, 4-n-octilfenol, 4-n-nonilfenol, bisfenol A, fenolftaleína e atrazina empregando extração em fase sólida (SPE) e cromatografia líquida acoplada ao espectrômetro de massas (LC-MS/MS), e verificar o potencial estrogênico das amostras usando o bioensaio Bioluminesce Yeast Estrogen Screening (BLYES). Os resultados mostraram a presença de seis dos 16 compostos investigados em pelo menos uma amostra de água tratada. A estrona foi detectada apenas uma vez. Concentrações de atrazina de até 687 ng L foram determinadas nas amostras provenientes do rio Capivari, e nas amostras de água tratada provenientes do rio Atibaia as concentrações não passaram de 42 ng L. A fenolftaleína foi determinada em apenas uma campanha em todas as amostras provenientes do rio Atibaia em concentrações de até 20 ng L. As concentrações médias de bisfenol A e triclosan foram 7 e 17 ng L, respectivamente. Nos mananciais foram determinados 13 dos 16 compostos investigados. Todas as amostras de água bruta e tratada apresentaram concentrações de cafeína que variaram significativamente entre os períodos de seca e cheia dos rios. As estações de tratamento de água de Campinas...

Water safety plans : methodologies for risk assessment and risk management in drinking-water systems

Vieira, J. M. Pereira
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2005 ENG
Relevância na Pesquisa
66.44%
Providing good and safe drinking-water is world-wide considered to be a fundamental political issue for public health protection, and must be the primary objective of water supply systems. Drinking-water quality control has currently been based on detection of pathogens and toxic concentrations of chemicals by means of monitoring programs and compliance with national or international guidelines and standards, relying mainly on indicator bacteria and chemicals maximum concentration levels. However, this methodology is often slow, complex and costly. Even for sophisticated and well-operated systems these monitoring schemes have proved to be inefficient in preventing waterborne diseases like, for instance, Giardia or Cryptosporidium outbreaks. From this evidence we can conclude that end-product testing is a reactive rather than preventive way to demonstrate confidence in good and safe drinking-water. This justifies the need for the formulation of a new approach in drinking-water quality control based on understanding of system vulnerability for contamination and on preventive means and actions necessary to guarantee the safety of the water supplied to the consumer. Water safety plan is a concept for risk assessment and risk management throughout the water cycle from the catchments to the point of consumption. This approach includes the identification of the hazards and introduction of control points that serve to minimize these potential hazards...

A comparative study of drinking water biofilm monitoring with flow cell and Propella™ bioreactors

Simões, Lúcia C.; Simões, M.; Vieira, M. J.
Fonte: International Water Association Publishing Publicador: International Water Association Publishing
Tipo: Artigo de Revista Científica
Publicado em //2012 ENG
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Monitoring of drinking water (DW) biofilm formation under different process conditions was performed using two distinct bioreactors: a Propella™ and a flow cell system. Biofilms were grown on polyvinyl chloride (PVC) and stainless steel (SS) coupons under laminar (Reynolds number: 2000) and turbulent (Reynolds number: 11000) flow. The parameters analysed were the numbers of total and cultivable bacteria. The impact of different process conditions was assessed after the biofilms reached steady-state. The number of total bacteria was mostly higher than those cultivable. Biofilm steady-state was achieved in 3 days in both bioreactors with adhesion surfaces under turbulent flow. Under laminar flow it was only achieved in 6 days. The numbers of total and cultivable bacteria in turbulent flow-generated biofilms were similar in both bioreactors, regardless of the adhesion surface tested. Under laminar flow, the Propella™ bioreactor allowed the formation of steady-state biofilms with a higher number of total and cultivable bacteria than the flow cell system. Comparing the effects of the flow regime on biofilm accumulation, only turbulent flow-generated biofilms formed on the flow cell system had a higher amount of total and cultivable bacteria than those formed under laminar flow. In terms of adhesion surface effects...

A review of nitrates in drinking water: maternal exposure and adverse reproductive and developmental outcomes

Manassaram,Deana M.; Backer,Lorraine C.; Moll,Deborah M.
Fonte: ABRASCO - Associação Brasileira de Saúde Coletiva Publicador: ABRASCO - Associação Brasileira de Saúde Coletiva
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2007 EN
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66.43%
In this review, we present an update on maternal exposure to nitrates in drinking water in relation to possible adverse reproductive and developmental effects, and discuss nitrates in drinking water in the United States. The current standard for nitrates in drinking water is based on retrospective studies and approximates a level that protects infants from methemoglobinemia, but no safety factor is built into the standard. The current standard applies only to public water systems. Animal studies have found adverse reproductive effects resulting from higher doses of nitrate or nitrite. The epidemiologic evidence of a direct exposure-response relationship between drinking water nitrate level and adverse reproductive effect is still not clear. However, some reports have suggested an association between exposure to nitrates in drinking water and spontaneous abortions, intrauterine growth restriction, and various birth defects. Uncertainties in epidemiologic studies include the lack of individual exposure assessment that would rule out confounding of the exposure with some other cause. We conclude that the current literature does not provide sufficient evidence of a causal relationship between exposure to nitrates in drinking water and adverse reproductive effects.

An analysis of the determinants of microbial contamination of drinking water in First Nations communities of Northern and Southern Ontario

Gray, Roger
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN
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Well publicized cases of drinking water contamination in First Nations communities in Ontario throughout the 1990s the first five years of the twentieth century have brought the issue of drinking water contamination in First Nations communities to the public’s attention. The most common form of drinking water contamination in First Nations reserves is microbial contamination. While cases of drinking water contamination have been reported in both northern and southern Ontario over the last decade and a half, it is unclear whether the nature and/or severity of drinking water contamination differs between First Nations communities in southern Ontario and more isolated communities in northern Ontario. In this document the cause(s) and the extent of microbial contamination of drinking water in two First Nations communities in southern Ontario and two First Nations communities in northern Ontario are examined and compared. The actions taken to address the drinking water contamination at all levels of government are also examined and compared between the communities in northern and southern Ontario. The results of this analysis suggest that while First Nations on southern Ontario appear to be more prone to drinking water contamination due to development and population pressure outside of the reserve...

Professionalizing Drinking Water Service Delivery in Small Towns of Haiti

Brault, Jean-Martin; Sanz, Zael; Le Bansais, Bruno
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Trabalho em Andamento
EN_US
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66.47%
This document aims to share lessons learned from the implementation of the World Bank financed component of the rural water supply and sanitation project (EPAR) in the Sud region after its final evaluation. Leading the reform of the drinking water and sanitation sector in Haiti, the EPAR of the National Directorate of Drinking Water and Sanitation (DINEPA) involved the construction or rehabilitation of drinking water schemes in small towns with fewer than 10,000 inhabitants in the Sud region. As a result of the project, there will be a real and sustainable increase in the water supply to Haiti’s populations of benefitting communities of the Sud region, thus providing improved access for most households. A long-term solution must be implemented in order to make the meters more affordable to the operators and thus enable them to continue expanding their customer base.

Quality of untreated water for public supplies in Florida

Hull, Robert W; Irwin, G. A. ( joint author ); Florida -- Bureau of Drinking Water and Special Programs; Florida -- Bureau of Water Resources Management; Florida -- Bureau of Geology; Geological Survey (U.S.)
Fonte: Bureau of Geology ( Tallahassee ) Publicador: Bureau of Geology ( Tallahassee )
Tipo: cartographic Formato: 12 maps : col. ; on sheet 57 x 71 cm.
Publicado em //1979 ENGLISH
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(Bibliography) Bibliography.; Each map shows concentration of 1 element.; In upper margin: United States Department of the Interior, Geological Survey.; Includes text, statistical tables, and inset of aquifers.; (Funding) Map series (Florida. Bureau of Geology); (Statement of Responsibility) by Robert W. Hull and G. A. Irwin ; prepared in cooperation with the Florida Department of Environmental Regulation, Bureau of Drinking Water and Special Programs, and Bureau of Water Resources Management.

Are endocrine disrupting compounds a health risk in drinking water?

Falconer, I.
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
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66.47%
There has been a great deal of international discussion on the nature and relevance of endocrine disrupting compounds in the environment. Changes in reproductive organs of fish and mollusks have been demonstrated in rivers downstream of sewage discharges in Europe and in North America, which have been attributed to estrogenic compounds in the effluent. The anatomical and physiological changes in the fauna are illustrated by feminization of male gonads. The compounds of greatest hormonal activity in sewage effluent are the natural estrogens 17β-estradiol, estrone, estriol and the synthetic estrogen ethinylestradiol. Androgens are also widely present in wastewaters. Investigations of anthropogenic chemical contaminants in freshwaters and wastewaters have shown a wide variety of organic compounds, many of which have low levels of estrogenic activity. In many highly populated countries the drinking water is sourced from the same rivers and lakes that are the recipients of sewage and industrial discharge. The River Thames which flows through London, England, has overall passed through drinking water and sewage discharge 5 times from source to mouth of the river. Under these types of circumstance, any accumulation of endocrine disrupting compounds from sewage or industry potentially affects the quality of drinking water. Neither basic wastewater treatment nor basic drinking water treatment will eliminate the estrogens...

A Handbook for Gram Panchayats : To Help Them Plan, Implement, Operate, Maintain and Manage Drinking Water Security

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
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The Department of Drinking Water Supply (DDWS), Ministry of Rural Development, Government of India launched the National Rural Drinking Water Program (NRDWP) on 1st April, 2009. The NRDWP builds on experiences gained through past efforts by many stakeholders and brings all existing rural drinking water initiatives under a single program. The focus of the NRDWP is to ensure drinking water security for all rural citizens in India. Drinking water security means providing every rural person with enough safe water for drinking, cooking and other domestic needs at all times and in all situations, including periods of drought and flood and for livestock. The Gram Panchayats (GP), as leaders and representatives of the community, has to take the lead in achieving this goal of drinking water security. The Gram Panchayats, through Village Water and Sanitation Committees (VWSCs), have to mobilize communities, educate them and ensure they get the necessary training and technical support to achieve drinking water security. The gram Sabha is the main platform for taking decisions and approving plans. The handbook seeks to serve as a quick reference for GP and VWSC on how to plan...

Implementing a protocol for selection and prioritisation of organic contaminants in the drinking water value chain: case study of Rand Water, South Africa

Ncube,EJ; Voyi,K; du Preez,H
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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Approaches that prioritise chemicals according to their importance as environmental contaminants have been developed by government agencies and private industries. However, it has been noticed that few approaches, such as one published by the United States Environmental Protection Agency (USEPA), address the needs of the drinking water industry. There is also no generic approach to the selection, prioritisation and monitoring of organic contaminants in the drinking water value chain. To safeguard drinking water industry customers, it was necessary to develop a generic protocol to assist with the identification of a list of organic contaminants for monitoring in the drinking water value chain. Once the protocol was developed, it was validated in a prototype drinking water value chain. This paper describes the implementation of such a generic protocol. The exercise comprised of testing each step of the protocol, from selection of the 'pool of organic contaminants' (Step I) to recommending the final priority list of organic contaminants (Step VII). Successful implementation of the protocol took place in the Rand Water (South Africa) drinking water value chain (from catchment to tap). Expert judgment was emphasized during the implementation as each step was validated and the opinion of key stakeholders used to shape the process. The tailor-made prioritisation criteria...

Spectrophotometric determination of fluoride in drinking water using aluminium complexes of triphenylmethane dyes

Barghouthi,Zaher; Amereih,Sameer
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
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A sensitive spectrophotometric determination of fluoride in drinking water has been developed using aluminium complexes of triphenylmethane dyes (chrome azurol B and malachite green) as spectrophotometric reagents. The method allowed a reliable determination of fluoride in the range of 0.5-4.0 mg-l-1 for chrome azurol B and 0.0-2.0 mg-l-1 for malachite green. The molar absorptivity for the complexes of chrome azurol B at 582 nm and malachite green at 622 nm is 1.44 x 10(4) and 2.56 x 10(4) l-mol-1cm-1, respectively. The sensitivity, detection limit, quantitation limit, and percentage recovery for 1.5 mg-l-1 fluoride for the method using chrome azurol B were found to be 0.125 ± 0.003 ug-ml-1, 0.2 mg-l-1, 0.5 mg-l-1, and 97.1 ± 4.2, respectively, and for malachite green were 0.143 ± 0.002 ug-l-1, 0.1 mg-l-1, 0.3 mg-l-1, and 97.9 ± 4.1, respectively.

Microbial quality of drinking water from groundtanks and tankers at source and point-of-use in eThekwini Municipality, South Africa, and its relationship to health outcomes

Singh,U; Lutchmanariyan,R; Wright,J; Knight,S; Jackson,S; Langmark,J; Vosloo,D; Rodda,N
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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Drinking water quality was investigated at source and corresponding point-of-use in 2 peri-urban areas receiving drinking water either by communal water tanker or by delivery directly from the distribution system to household-based groundtanks with taps. Water quality variables measured were heterotrophic bacteria, total coliforms, E. coli, conductivity, turbidity, pH, and total and residual chlorine. Water quality data were analysed together with an existing epidemiological database to investigate links between microbial quality of drinking water, household demographics, health outcomes, socio-economic status, hygiene and sanitation practices. Groundtank households had better quality drinking water than households using storage containers filled from communal tankers. Uncovered storage containers had the poorest microbial water quality among all storage containers. All stored water did not meet drinking water standards, although mains water did. Households with children under 5 years and using open-topped containers had the poorest water quality overall. Households with groundtanks had the best water quality at point-of-use, but did not have the lowest occurrence of health effects. Although groundtanks were supplied together with urine diversion (UD) toilets and hygiene education...

Efficacy of conventional drinking water treatment processes in removing problem-causing phytoplankton and associated organic compounds

Ewerts,H; Swanepoel,A; du Preez,HH
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
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Seven phytoplankton groups were recorded in the source water supplied to South Africa's largest conventional drinking water treatment plant (DWTP). Two phytoplankton genera, Anabaena and Ceratium were identified as the problem-causing phytoplankton due to their ability to interfere with the water treatment process and negatively impact on water quality. The objectives of this study were to identify problem-causing phytoplankton genera and investigate the efficacy of unit processes in removing phytoplankton genera and associated organic compounds. Phytoplankton and organic compound data were obtained from four different sampling localities throughout the treatment plant and statistically analysed to evaluate the removal efficiencies of unit processes. The highest percentage removal for the Cyanophyceae average seasonal concentration (> 1 000 cells/mℓ) was recorded at 98%, while the highest percentage removal for the Dinophyceae average seasonal concentration (± 9 cells/mℓ) was recorded at 100%. Microcystis and Anabaena were removed by the processes of coagulation, flocculation and sedimentation (> 95%), while Ceratium cells were removed by sand filtration (> 80%). Ineffective removal of Ceratium by coagulation, flocculation and sedimentation (and subsequent penetration to the sand filtration step) will negatively impact on filter run times when these phytoplankton genera are present in high concentrations in the source water. Total photosynthetic pigments (TPP) were removed effectively by all the different water treatment processes. Not enough statistical evidence could be displayed to suggest effective removal of geosmin in this conventional water treatment plant. With good removal of intact cyanobacteria cells during coagulation...

Prevalence of enterohaemorrhagic Escherichia coli O157: H7 in drinking water and its predicted impact on diarrhoeic HIV/AIDS patients in the Amathole District, Eastern Cape Province, South Africa

Momba,MNB; Abong'o,BO; Mwambakana,JN
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2008 EN
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Immunosuppressed persons such as HIV/AIDS patients are at risk of acquiring diarrhoeal infections from water-borne E. coli O157:H7. In the present study, we investigated the prevalence of E. coli O157:H7 in drinking water collected from selected distribution systems within the Amathole District of the Eastern Cape and its predicted impact on diarrhoeic conditions of HIV/AIDS persons living in this area. One hundred and eighty water samples and 360 stool swabs from confirmed and non-confirmed HIV/AIDS diarrhoeic patients were analysed. Escherichia coli O157:H7 were isolated using enrichment culture and confirmed using molecular techniques. Of the 180 drinking water samples, 46 (25.56%) were positive for E. coli O157. The prevalence of E. coli O157 in the stools was at 36.39% (131/360) of which 56.5% (74/131) and 43.5% (57/131) were from stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Molecular analysis of 27, 25 and 29 representative presumptive E. coli O157 from water and stools of confirmed and non-confirmed HIV/AIDS patients, respectively, revealed that 14.81%, 36% and 17.24% of the isolates were E. coli O157:H7. The findings predicted a possible link between E. coli O157:H7 isolated from drinking water and diarrhoeic conditions of both confirmed and non-confirmed HIV/AIDS patients visiting Frere Hospital for treatment.

Application of a basic monitoring strategy for Cryptosporidium and Giardia in drinking water

Sigudu,MV; du Preez,HH; Retief,F
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2014 EN
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Despite the health risks associated with exposure to Cryptosporidium and Giardia, there is no uniform approach to monitoring these protozoan parasites across the world. In the present study, a strategy for monitoring Cryptosporidium and Giardia in drinking water was developed in an effort to ensure that the risk of exposure to these organisms and the risks of non-compliance to guidelines are reduced. The methodology developed will be applicable to all water supply systems irrespective of size and complexity of the purification works. It is based on monitoring procedures proposed by the US Environmental Protection Agency, the Drinking Water Inspectorate, Australia and New Zealand, as well as the risk-based procedure followed by Northern Ireland. The monitoring strategy developed represents a preventative approach for proactively monitoring Cryptosporidium and Giardia species in drinking water. The strategy consists of 10 steps: (i) assessment of the monitoring requirements, (ii) description and characterisation of the source water types, (iii) abstraction of source water, (iv) assessment of the water purification plant, (v) water quality monitoring, (vi) cryptosporidiosis and giardiasis outbreak, (vii) risk assessment, (viii) sample collection and laboratory processing...

Survey of disinfection efficiency of small drinking water treatment plants: challenges facing small water treatment plants in South Africa

Momba,MNB; Obi,CL; Thompson,P
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2009 EN
Relevância na Pesquisa
76.36%
A survey involving 181 water treatment plants across 7 provinces of South Africa: Mpumalanga, Limpopo, North West, Free State, KwaZulu-Natal, Eastern Cape and Western Cape was undertaken to identify the challenges facing small water treatment plants (SWTPs) in South Africa . Information gathered included ownership and design capacity of the plants, water sources, and various methods of disinfection, equipment currently employed and performance of the treatment plants. In general, the majority (over 80%) of the SWTPs surveyed in the designated provinces were owned by the district municipalities. The designed capacities of these plants varied between 1 and 60 Mℓ/d; the smallest capacity was 100 m³/d and the largest 120 Mℓ/d. The small water treatment plants abstracted their raw water from either surface or groundwater or a combination of both water sources with greater preponderance for surface water sources (over 86%). Water treatment practices were noted to be the conventional types mainly coagulation, flocculation, sedimentation, filtration and disinfection. Two types of coagulants namely polyelectrolyte (66%) and alum (18%) were commonly used by the water treatment plants across the provinces studied. Rapid gravity filtration...

Heterotrophic plate count vs. in situ bacterial 16S rRNA gene amplicon profiles from drinking water reveal completely different communities with distinct spatial and temporal allocations in a distribution net

Burtscher,MM; Zibuschka,F; Mach,RL; Lindner,G; Farnleitner,AH
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2009 EN
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Heterotrophic plate count using ISO 6222 agar (HPC) vs. in situ bacterial (DF) community structure from corresponding samples of a drinking water distribution system were investigated by 16S rRNA gene-based polymerase chain reaction denaturing gradient gel electrophoresis (PCR DGGE) profiling. The investigation regime covered 10 different sampling locations and 2 points in time (t1, t2). In order to ensure accurate and reproducible 16S rRNA gene profile analysis, rigorous methodical evaluation and standardisation procedures were undertaken (DGGE optimisation, replication of PCR, multiple-lane standardisation, representative sampling volume determination, application of multiple similarity coefficients). The reproducibility level of the profile analysis was determined to be > 90% similarity. Two completely different communities were revealed from HPC vs. DF as indicated by DGGE analysis and sequencing. HPC populations could be identified as ubiquitously occurring cultivable copiotrophic microbes, whilst most DF sequences could be allocated to sequences from microorganisms found in oligotrophic aquatic environments. Spatial- and temporal-based 16S rRNA gene amplicon profile analysis from recovered communities further revealed contrasting results. As proven by Jackknife simulations...

Assessment of Cryptosporidium in wastewater reuse for drinking water purposes: a case study for the city of Amsterdam, The Netherlands

Rietveld,LC; Meijer,L; Smeets,PWMH; van der Hoek,JP
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 EN
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Wastewater reuse is becoming increasingly important for supplementing drinking water supply needs and/or to reduce costs in many communities around the world. However, wastewater reuse can result in a potential transmission route for infectious agents. Therefore, the occurrence of Cryptosporidium was assessed in a treatment plant geared for the production of drinking water from wastewater effluent and the results were compared to those on an existing typical drinking water treatment plant operated by Waternet, the water cycle company of Amsterdam, The Netherlands, and its surrounding areas. The assessment was done using Monte-Carlo simulation and probability density functions to determine the occurrence of Cryptosporidium in raw surface water and wastewater effluent and the removal in different treatment steps. From the research conducted, it was concluded that under normal conditions, drinking water that meets Dutch drinking water quality standards could also be produced from treated wastewater effluent. However, additional redundancy should be built in to meet the standards under extreme operating conditions.

Inequities in access to and use of drinking water services in Latin America and the Caribbean

Soares,Luiz Carlos Rangel; Griesinger,Marilena O.; Dachs,J. Norberto W.; Bittner,Marta A.; Tavares,Sonia
Fonte: Organización Panamericana de la Salud Publicador: Organización Panamericana de la Salud
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2002 EN
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66.5%
Objective. To identify and evaluate inequities in access to drinking water services as reflected in household per capita expenditure on water, and to determine what proportion of household expenditures is spent on water in 11 countries of Latin America and the Caribbean. Methods. Using data from multi-purpose household surveys (such as the Living Standards Measurement Survey Study) conducted in 11 countries from 1995 to 1999, the availability of drinking water as well as total and per capita household expenditures on drinking water were analyzed in light of socioeconomic parameters, such as urban vs. rural setting, household income, type and regularity of water supply service, time spent obtaining water in homes not served by running water, and type of water-purifying treatment, if any. Results. Access to drinking water as well as total and per capita household expenditures on drinking water show an association with household income, economic conditions of the household, and location. The access of the rural population to drinking water services is much more restricted than that of the urban population for groups having similar income. The proportion of families having a household water supply system is comparable in the higher-income rural population and the lower-income urban population. Families without a household water supply system spend a considerable amount of time getting water. For poorer families...