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1.
Artigo em Inglês | MEDLINE | ID: mdl-31652957

RESUMO

Uganda was among the first countries in Africa that pioneered Water Safety Plan (WSP) development and implementation, with the first WSP dating back to 2002. The objective of this study was to assess WSP status in Uganda, focusing on the experience of the National Water and Sewerage Corporation (NWSC), in order to understand the factors that influenced it and strategies for scaling-up. This study consisted of a review of documentation for 20 WSPs, 42 interviews, a focus group discussion and four field visits. Results show that the development of the 20 WSPs over the last 15 years was largely incomplete and diverse. Most of the WSPs focused on system assessment and improvement, but failed to include WSP monitoring, verification and management. The monitoring of control measures was implemented in nine of the 20 systems, while verification took place in the form of internal (5/20) and external (2/20) auditing. The main barriers identified to WSP implementation were inadequate training, team composition and deployment, mistaken perception and inability to evaluate WSP effectiveness. Conversely, the main enabling factors were management commitment, public health responsibility, good customer relations, financial availability and reliable laboratories. These findings suggest a need for more institutionalization of WSPs with improved coordination across stakeholder groups.

2.
Int J Hyg Environ Health ; 222(4): 615-627, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30744955

RESUMO

The World Health Organization has recommended Water Safety Plans (WSPs), a holistic risk assessment and risk management approach, for drinking-water suppliers across low-, middle- and high-income countries, since publishing its 2004 Guidelines for Drinking-Water Quality. While rapid WSP adoption has occurred, capacity is still catching up to implementation needs. Many countries and regions lack case examples, legal requirements, and training resources for WSPs, corresponding to widespread capacity shortfall in the water supply sector. We undertook a comprehensive review of the literature on capacity building and training for WSPs, with the goal of providing recommendations for multiple stakeholder groups at the scales of individual utilities, national governments, and intermediate units of governance. We propose a WSP training taxonomy and discuss it in relation to the stages of learning (introduction, practice, and reinforcement); describe the importance of customizing training to the target group, local language and circumstances; highlight the relevance of auditing for evaluating change over time; and call for robust methods to monitor WSP capacity development.


Assuntos
Fortalecimento Institucional , Qualidade da Água/normas , Ensino , Abastecimento de Água
3.
Chemosphere ; 220: 176-184, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30583210

RESUMO

Alternative disinfection technologies may overcome some of the limitations of conventional treatment applied in swimming pools: chlorine-resistant pathogens (e.g. Cryptosporidium oocysts and Giardia cysts) and the formation of chlorinated disinfection byproducts. In this paper, results of full scale validation of an alternative disinfection technology UVOX Redox® (hereinafter referred to as UVOX) that combines ozonation and UV irradiation are presented. The performance was assessed in terms of microbial inactivation, disinfection byproduct formation and micropollutant removal. UVOX was able to achieve 1.4-2.7 log inactivation of Bacillus subtilis spores at water flows between 20 and 76 m³/h. Lower formation of trichloromethane and dichloroacetic acid was observed with UVOX followed by chlorination when compared to chlorination alone. However, due to the use of ozone and the presence of bromide in the pool water, the formation of trihalomethanes and haloacetic acids shifted to more brominated byproducts. Chlorine alone was able to remove the target micropollutants: acetaminophen, atenolol, caffeine, carbamazepine, estrone, estradiol, and venlafaxine (>97% removal) after 24 h, with the exception of ibuprofen (60% removal). The application of UVOX in chlorinated water enhanced the removal of ibuprofen. The application of UVOX could lower the usage of chlorine to the level that provides an adequate residual disinfection effect.


Assuntos
Bacillus subtilis/efeitos dos fármacos , Cloro/química , Desinfecção/métodos , Ozônio , Piscinas , Raios Ultravioleta , Purificação da Água/métodos , Halogenação , Viabilidade Microbiana/efeitos da radiação , Oxirredução , Poluentes Químicos da Água/análise
4.
Int J Hyg Environ Health ; 221(8): 1107-1115, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30145117

RESUMO

Possible transmission pathways of fungi in indoor swimming pool facilities were assessed through fungal counting in different areas of the facilities and typing of the collected fungal isolates. Air, water and surface samples were collected from seven different indoor swimming pool facilities. Fungal species were identified based on their internal transcribed spacer (ITS) sequences. Maximum fungal concentrations of 6.2 CFU/cm2, 1.39 CFU/100 mL, and 202 CFU/m³ were found on surfaces, in water and air, respectively. In total, 458 isolates were obtained, belonging to 111 fungal species, of which 50 species were clinically relevant. Phialophora oxyspora (13.3%) and Trichosporon dohaense (5.0%) were the most frequently isolated species and were merely detected on floors, as were the dermatophytes, Trichophyton interdigitale and T. rubrum. Penicillium spp. and Aspergillus spp. were the dominant fungi in water and air. No typical patterns of fungal concentrations along the preferential pathways of pool visitors were observed, however, sites where pool visitors converge while moving from one room (e.g. dressing room) to another (e.g. shower room) and walking barefoot displayed the highest fungal concentrations thus posing the highest risk of contamination. The dispersal of fungi on floors is most likely facilitated by the pool visitors and cleaning tools. Clinically relevant fungi, including the ones rarely identified in nature, were widely detected on floors, in water and in air, as well as on cleaning tools and flexibeams. Preventive measures such as cleaning should minimize the prevalence of clinically relevant fungi in swimming pool facilities since these potentially pose health risks to those vulnerable for infections.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Poluição do Ar em Ambientes Fechados/análise , Fungos/isolamento & purificação , Micoses/transmissão , Piscinas , Poluentes da Água/isolamento & purificação , Microbiologia do Ar , DNA Fúngico/análise , Detergentes , Monitoramento Ambiental , Pisos e Cobertura de Pisos , Fungos/genética , Humanos , Materiais de Ensino , Microbiologia da Água
5.
Int J Hyg Environ Health ; 220(7): 1152-1160, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28716483

RESUMO

The density of fungal contamination and the fungal diversity in an indoor swimming pool facility were assessed. A total of 16 surface samples and 6 water samples were analysed by using a combination of different (semi-) selective culture media. Isolated fungal colonies were identified to the genus or species level by sequencing of the internal transcribed spacer (ITS). The highest fungal counts in water and on surfaces were in the recreational pool (17CFU/100mL) and on a flexibeam (5.8CFU/cm2), respectively as compared with low counts (<0.1CFU/cm2) on the diving platform, bench tops and walls. The 357 obtained isolates belonged to 79 species and species complexes, 42 of which known as clinically relevant. Phialophora oxyspora (13.7%) and Phoma spp. (12.3%) were the most frequently identified groups. We demonstrated that despite chlorine treatment and regular cleaning of surfaces both water and surfaces were commonly infested with fungi, including many clinically relevant species.


Assuntos
Fungos/isolamento & purificação , Piscinas , Microbiologia da Água , Análise de Variância , Contagem de Colônia Microbiana , Equipamentos e Provisões/microbiologia , Pisos e Cobertura de Pisos , Fungos/genética , Humanos , Países Baixos , Phialophora/isolamento & purificação , Análise de Sequência , Água
6.
J Water Health ; 14(5): 851-863, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27740550

RESUMO

Over past decades strategies for improving access to drinking water in cities of the Global South have mainly focused on increasing coverage, while water quality has often been overlooked. This paper focuses on drinking water quality in the centralized water supply network of Lilongwe, the capital of Malawi. It shows how microbial contamination of drinking water is unequally distributed to consumers in low-income (unplanned areas) and higher-income neighbourhoods (planned areas). Microbial contamination and residual disinfectant concentration were measured in 170 water samples collected from in-house taps in high-income areas and from kiosks and water storage facilities in low-income areas between November 2014 and January 2015. Faecal contamination (Escherichia coli) was detected in 10% of the 40 samples collected from planned areas, in 59% of the 64 samples collected from kiosks in the unplanned areas and in 75% of the 32 samples of water stored at household level. Differences in water quality in planned and unplanned areas were found to be statistically significant at p < 0.05. Finally, the paper shows how the inequalities in microbial contamination of drinking water are produced by decisions both on the development of the water supply infrastructure and on how this is operated and maintained.


Assuntos
Água Potável/microbiologia , Qualidade da Água , Cidades , Fezes/microbiologia , Malaui , Fatores Socioeconômicos , Abastecimento de Água
7.
Environ Sci Pollut Res Int ; 23(14): 14431-41, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27068900

RESUMO

The occurrence of 32 pharmaceuticals and 14 UV filters in swimming pools and spas was studied. Fifty-one water samples were collected from 17 pools located in sport centres and hotels in Catalonia, Spain. The samples were analysed by liquid chromatography-tandem mass spectrometry. The pharmaceuticals atenolol, carbamazepine, hydrochlorothiazide, metronidazole, ofloxacin, sulfamethoxazole, acetaminophen, ibuprofen, ketoprofen and phenazone were measured in water samples at concentrations higher than their limit of quantification (LOQ). The highest concentration of any individual pharmaceutical was measured for the diuretic hydrochlorothiazide (904 ng/L). The most frequently detected pharmaceutical was carbamazepine, as it was observed in more than half of all the water samples measured (53 %, 27/51). The UV filters at concentrations higher than LOQ in water samples were BP1, BP2, BP3, BP8, THB, 4DHB, 4MBC, OD-PABA, 1HBT, MeBT and DMeBT. The highest concentration of UV filter observed was 4MBC (69.3 ng/L) while the most frequent UV filters in the samples were 1HBT (59 %, 30/51). The results also showed that pharmaceuticals and UV filters were most frequently found in spas. Finally, from a water treatment technology perspective, the lowest occurrence of pharmaceuticals was in the pools applying sand filters followed by disinfection by sodium hypochlorite, while the lowest occurrence of UV filters was in the pools applying coagulation, sand filtration, UV and salt electrolysis.


Assuntos
Poluentes Químicos da Água/análise , Atenolol/análise , Banhos , Carbamazepina/análise , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Piscinas , Espectrometria de Massas em Tandem , Raios Ultravioleta , Purificação da Água/métodos
8.
Water Res ; 79: 1-9, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25965883

RESUMO

Membrane aeration represents between 35 and 50% of the operational cost of membrane bioreactors (MBR). New automatic control systems and/or module configurations have been developed for aeration optimization. In this paper, we briefly describe an innovative MBR air scour control system based on permeability evolution and present the results of a full-scale validation that lasted over a 1-year period. An average reduction in the air scour flow rate of 13% was achieved, limiting the maximum reduction to 20%. This averaged reduction corresponded to a decrease in energy consumption for membrane aeration of 14% (0.025 kWh m(-3)) with maximum saving rates of 22% (0.04 kWh m(-3)). Permeability and fouling rate evolution were not affected by the air scour control system, as very similar behavior was observed for these variables for both filtration lines throughout the entire experimental evaluation period of 1 year.


Assuntos
Reatores Biológicos , Membranas Artificiais , Incrustação Biológica , Filtração/instrumentação , Filtração/métodos , Permeabilidade , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos
9.
Water Res ; 46(11): 3421-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22520860

RESUMO

Membrane bioreactor (MBR) technology has become relatively widespread as an advanced treatment for both industrial and municipal wastewater, especially in areas prone to water scarcity. Although operational cost is a key issue in MBRs, currently only a few crucial papers and inventions aimed to optimise and enhance MBR efficiency have been published. The present review summarises the available solutions in the area of automatic control systems and widely explores the advances in automation and control for MBRs. In this review of state of the art, different control systems are evaluated comparatively, distinguishing between control systems used for the filtration process and those used for the biological process of MBRs and describing the challenge faced by integrated control systems. The existing knowledge is classified according to the manipulated variables, the operational mode (open-loop or closed-loop) and the controlled variables used.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/instrumentação , Automação , Desenho de Equipamento , Filtração , Eliminação de Resíduos Líquidos/métodos
10.
Bioresour Technol ; 106: 50-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22206919

RESUMO

In start-up periods low MLSS concentration may lead to fouling phenomena and uncommon frequency of chemical cleanings using membrane bioreactors. A knowledge-based control module for the optimisation of start-up procedures in membrane bioreactors is presented and validated in this paper. The main objective of the control module is to accelerate the growth of MLSS and the achievement of the design flux while minimising the fouling phenomenon during start-up periods. The module was validated in a pilot-scale membrane bioreactor with the University of Cape Town configuration and submerged flat sheet microfiltration membranes. The knowledge of the control system was represented as a decision tree before being implemented. A fully satisfactory start-up, both for the filtration and the biological phase, was obtained in 20 days, saving time and preserving the membrane integrity.


Assuntos
Reatores Biológicos , Conhecimento , Membranas Artificiais , Automação , Árvores de Decisões , Reprodutibilidade dos Testes
11.
Bioresour Technol ; 101(11): 3984-91, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20137918

RESUMO

The performance of an MBR pilot plant for biological nutrient removal was evaluated during 210days of operation. The set point values for the internal recycles were determined in advance with the use of an optimisation spreadsheet based on the ASM2d model to optimise the simultaneous removal of C, N and P. The biological nutrient removal (BNR) efficiencies were high from the start of operation with COD and N removal efficiencies of 92+/-6% and 89+/-7, respectively. During the course of the experiment P removal efficiencies increased and finally a P-removal efficiency of 92% was achieved. The activity of poly-phosphate accumulating organisms (PAOs) and denitrifying poly-phosphate accumulating organisms (DPAOs) increased and the specific phosphate accumulation rates after 150days of operation amounted to 13.6mgPg(-1)VSSh(-1) and 5.6mgPg(-1)VSSh(-1), for PAOs and DPAOs, respectively.


Assuntos
Reatores Biológicos , Membranas Artificiais , Fósforo/isolamento & purificação , Poluentes da Água/isolamento & purificação , Projetos Piloto
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