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1.
PLoS One ; 16(2): e0247417, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33630884

RESUMO

The paper assessed access to WASH service in the Jariban district of Somalia. One hundred and sixty-seven households were sampled to administer a questionnaire. Central tendency and logistical regression were used to analyse the data in SPSS 26. The findings show that access to safe drinking water sources is 57.5%. Of the 42.5% of respondents who did not access safe drinking water source, only 10.8% confirmed that they treat drinking water at the point of use. The main reason for household water treatment was the positive mindset (.272) of the household head towards water treatment. The majority (80.2%) of the respondents access approximately 13 litres per person per day. Woman-headed households were more likely to treat water before drinking than male-headed households. Only 26.9% of the respondents accessed basic sanitation. Of the respondents, 55.7% did not share latrines, while 44.3% share resulting in open defecation. WASH access in the study area remains low, resulting in health-related risks, including diarrhoeal disease. The limitation is that the paper only focused on access to WASH facilities in fragile contexts. A cross-sectional analysis of biological, physical and chemical properties of water at the source and point of use is recommended for further research.


Assuntos
Purificação da Água/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Água/química , Características da Família , Feminino , Humanos , Higiene , Masculino , Saneamento/estatística & dados numéricos , Fatores Socioeconômicos , Somália , Inquéritos e Questionários/estatística & dados numéricos , Banheiros/estatística & dados numéricos
2.
BMC Microbiol ; 20(1): 346, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33183235

RESUMO

BACKGROUND: Access to safe water for drinking and domestic activities remains a challenge in emerging economies like South Africa, forcing resource-limited communities to use microbiologically polluted river water for personal and household purposes, posing a public health risk. This study quantified bacterial contamination and the potential health hazards that wastewater treatment plant (WWTP) workers and communities may face after exposure to waterborne pathogenic bacteria in a WWTP and its associated surface water, respectively. RESULTS: Escherichia coli (Colilert®-18/ Quanti-Tray® 2000) and enterococci (Enterolert®/ Quanti-Tray® 2000) were quantified and definitively identified by real-time polymerase chain reaction targeting the uidA and tuf genes, respectively. An approximate beta-Poisson dose-response model was used to estimate the probability of infection (Pi) with pathogenic E. coli. Mean E. coli concentration ranged from 2.60E+ 02/100 mL to 4.84E+ 06/100 mL; enterococci ranged from 2.60E+ 02/100 mL to 3.19E+ 06/100 mL across all sampled sites. Of the 580 E. coli isolates obtained from this study, 89.1% were intestinal, and 7.6% were extraintestinal pathogenic E. coli. The 579 enterococci obtained were 50.4% E. faecalis (50.4%), 31.4% E. faecium, 3.5%, E. casseliflavus and 0.7% E. gallinarum. The community health risk stemming from the use of the water for recreational and domestic purposes revealed a greater health risk (Pi) from the ingestion of 1 mL of river water from upstream (range, 55.1-92.9%) than downstream (range, 26.8-65.3%) sites. The occupational risk of infection with pathogenic E. coli for workers resulting from a once-off unintentional consumption of 1 mL of water was 0% (effluent) and 23.8% (raw influent). Multiple weekly exposures of 1 mL over a year could result in a Pi of 1.2 and 100% for the effluent and influent, respectively. CONCLUSION: Our findings reveal that there is a potentially high risk of infection for WWTP workers and communities that use river water upstream and downstream of the investigated WWTP.


Assuntos
Águas Residuárias/microbiologia , Purificação da Água/estatística & dados numéricos , Enterococcus/classificação , Enterococcus/genética , Enterococcus/isolamento & purificação , Enterococcus/patogenicidade , Exposição Ambiental/análise , Exposição Ambiental/estatística & dados numéricos , Escherichia coli/classificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Medição de Risco , Rios/microbiologia , África do Sul , Purificação da Água/normas
3.
Proc Natl Acad Sci U S A ; 117(29): 16898-16907, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32631989

RESUMO

Although the Flint, Michigan, water crisis renewed concerns about lead (Pb) in city drinking water, little attention has been paid to Pb in private wells, which provide drinking water for 13% of the US population. This study evaluates the risk of Pb exposure in children in households relying on private wells. It is based on a curated dataset of blood Pb records from 59,483 North Carolina children matched with household water source information. We analyze the dataset for statistical associations between children's blood Pb and household drinking water source. The analysis shows that children in homes relying on private wells have 25% increased odds (95% CI 6.2 to 48%, P < 0.01) of elevated blood Pb, compared with children in houses served by a community water system that is regulated under the Safe Drinking Water Act. This increased Pb exposure is likely a result of corrosion of household plumbing and well components, because homes relying on private wells rarely treat their water to prevent corrosion. In contrast, corrosion control is required in regulated community water systems. These findings highlight the need for targeted outreach to prevent Pb exposure for the 42.5 million Americans depending on private wells for their drinking water.


Assuntos
Água Potável/normas , Intoxicação do Sistema Nervoso por Chumbo na Infância/epidemiologia , Chumbo/sangue , Setor Privado/estatística & dados numéricos , Setor Público/estatística & dados numéricos , Poços de Água , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , North Carolina , Purificação da Água/economia , Purificação da Água/estatística & dados numéricos
4.
Isr Med Assoc J ; 21(9): 589-594, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31542902

RESUMO

BACKGROUND: Cryptosporidium is a major threat to water supplies worldwide. Various biases and obstacles in case identification are recognized. In Israel, Cryptosporidiosis was included among notifiable diseases in 2001 in order to determine the burden of parasite-inflicted morbidity and to justify budgeting a central drinking water filtration plant. OBJECTIVES: To summarize the epidemiologic features of 14 years of Cryptosporidium surveillance and to assess the effects of advanced water purification treatment on the burden of disease. METHODS: From 2001 to 2014, a passive surveillance system was used. Cases were identified based on microscopic detection in stool samples. Confirmed cases were reported electronically to the Israeli Ministry of Health. Overall rates as well as age, gender, ethnicity and specific annual incidence were calculated per 100,000 population in five age groups: 0-4, 5-14, 15-44, 45-64, > 65 years. RESULTS: A total of 522 Cryptosporidium cases were reported in all six public health districts. More cases were detected among Jews and among males, and mainly in young children, with a seasonal peak during summer. The Haifa sub-district reported 69% of the cases. Most were linked to an outbreak from the summer of 2008, which was attributed to recreational swimming pool activity. Cases decreased after installation of a central filtration plant in 2007. CONCLUSIONS: As drinking water in Israel is treated to maximal international standards, the rationale for further inclusion of Cryptosporidium among mandatory notifiable diseases should be reconsidered. Future surveillance efforts should focus on timely detection of outbreaks using molecular high-throughput testing.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/isolamento & purificação , Monitoramento Epidemiológico , Política de Saúde , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Incidência , Lactente , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Estações do Ano , Fatores Sexuais , Purificação da Água/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos , Adulto Jovem
5.
Environ Health Prev Med ; 23(1): 46, 2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30261840

RESUMO

BACKGROUND: Diarrheal disease attributable to water and sanitation can be prevented using point-of-use water treatment. In Ethiopia, a small number of households treat water at point-of-use with appropriate methods. However, evidence on factors associated with household use of these treatment methods is scarce. Therefore, this study is intended to explore the household use of appropriate point-of-use water treatment and associated factors in Ethiopia. METHODS: The data of 2005, 2011, and 2016 Ethiopian demographic and health surveys were used for analysis. Households reportedly treating water with bleach, boiling, filtration, and solar disinfection in each survey are considered as treating with appropriate treatment methods. Household water treatment with these treatment methods and factors associated was assessed using bivariate and multivariable regression. In addition, a region level difference in the treatment use was assessed by using multilevel modeling. RESULTS: The number of households that reported treating water with appropriate water treatment methods was 3.0%, 8.2%, and 6.5% respectively in 2005, 2011, and 2016. Household heads with higher education had 5.99 (95% CI = 3.48, 10.33), 3.61 (95% CI = 2.56, 5.07), and 3.43 (95% CI = 2.19, 6.37) times higher odds of using the treatment methods respectively in 2005, 2011, and 2016 compared to household heads who had no education. There was a significantly high number of households that used appropriate water treatment methods in 2011 (AOR = 2.78, 95% CI = 2.16, 3.57) and 2016 (AOR = 2.18, 95% CI = 1.64, 3.89) compared to 2005 data. In pooled data analysis, the reported use of the treatment methods is associated with household head education, residency, drinking water sources, and owning radio and television. From a multilevel modeling, within-region variation is higher than between-region variations in the use of treatment methods in each survey. CONCLUSIONS: Below 10% of households reportedly treating water at point-of-use in each survey attributable to different factors. Designing intervention strategies for wide-scale use of treatment methods at the country level is fundamental.


Assuntos
Purificação da Água/métodos , Purificação da Água/estatística & dados numéricos , Adolescente , Adulto , Etiópia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores Socioeconômicos , Inquéritos e Questionários , Purificação da Água/normas , Abastecimento de Água/estatística & dados numéricos , Adulto Jovem
6.
Sci Total Environ ; 643: 936-945, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29960230

RESUMO

The work addresses the effect of total suspended solids (TSS) on disinfection by peracetic acid (PAA) concerning both PAA decay and bacterial inactivation kinetics. The effect of TSS on PAA decay was evaluated at five TSS concentrations (5, 40, 80, 120 and 160 mg/L), obtained from stock TSS solutions prepared from activated sludge samples. The influence of the soluble matter associated to the suspended solids on PAA decay was evaluated separately, using the same stock TSS solution after the removal of solids by filtration. The contributions of suspended and soluble fractions were found to be independent, and a predictive model formed by two additive sub-models was proposed to describe the overall PAA decay kinetics. Moreover, an uncertainty analysis was performed by a series of Monte Carlo simulations to propagate the uncertainties associated to the coefficients of the model. Then, the disinfectant dose (mg/L min) was highlighted as the main parameter determining disinfection efficiency on a pure culture of E. coli and an inactivation kinetic model was developed based on the response of E. coli to various PAA doses. Finally, the effect of TSS (40 and 160 mg/L) on the inactivation of free-swimming E. coli was investigated at two PAA doses (5 and 20 mg/L min). TSS reduced inactivation extent an average of 0.4 logs at 5 mg/L min and 1.5 logs at 20 mg/L min. It was hypothesized that this might be due to the formation of bacteria aggregates as defense mechanism against disinfection, enhanced by the presence of solids.


Assuntos
Desinfetantes/metabolismo , Ácido Peracético/metabolismo , Purificação da Água/métodos , Desinfecção , Escherichia coli , Cinética , Modelos Estatísticos , Purificação da Água/estatística & dados numéricos
7.
Water Environ Res ; 90(8): 738-747, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031407

RESUMO

To enable small communities to benchmark the energy efficiency of their water resource recovery facilities (also known as wastewater treatment facilities), multiple linear regression models of electric and overall energy intensity (kWh/m3) were created using data from Nebraska and Pennsylvania. Key variables found to be significant include: facility type, supplemental energy usage for sludge treatment, average flow, percent design flow, climate controlled floor area, effluent NH3-N, and influent CBOD5. The results show that energy use models for small systems differ from those for large facilities and that regulatory changes can affect energy usage. Step changes in the data for facilities that changed operators highlight the importance of operational decisions on energy efficiency for small facilities serving fewer than 10,000 people. Differences were observed between the models of data from specific states. Although these models may not include all factors that account for variability in energy use, they can provide a reference benchmark for small WRRFs.


Assuntos
Benchmarking , Conservação de Recursos Energéticos/economia , Instalações de Eliminação de Resíduos/economia , Eliminação de Resíduos Líquidos/economia , Purificação da Água/estatística & dados numéricos , Modelos Teóricos , Nebraska , Purificação da Água/economia , Recursos Hídricos
8.
Integr Environ Assess Manag ; 14(4): 447-462, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29603595

RESUMO

Mediterranean-African countries (MACs) face a major water crisis. The annual renewable water resources are close to the 500 m3 /capita threshold of absolute water scarcity, and water withdrawals exceed total renewable water resources by 30%. Such a low water availability curbs economic development in agriculture, which accounts for 86% of freshwater consumption. The analysis of the current situation of wastewater treatment, irrigation, and water management in MACs and of the research projects targeted to these countries indicates the need for 1) an enhanced capacity to analyze water stress, 2) the development of water management strategies capable of including wastewater reuse, and 3) development of locally adapted water treatment and irrigation technologies. This analysis shaped the MADFORWATER project (www.madforwater.eu), whose goal is to develop a set of integrated technological and management solutions to enhance wastewater treatment, wastewater reuse for irrigation, and water efficiency in agriculture in Egypt, Morocco, and Tunisia. MADFORWATER develops and adapts technologies for the production of irrigation-quality water from drainage canals and municipal, agro-industrial, and industrial wastewaters and technologies for water efficiency and reuse in agriculture, initially validated at laboratory scale, to 3 hydrological basins in the selected MACs. Selected technologies will be further adapted and validated in 4 demonstration plants of integrated wastewater treatment and reuse. Integrated strategies for wastewater treatment and reuse targeted to the selected basins are developed, and guidelines for the development of integrated water management strategies in other basins of the 3 target MACs will be produced. The social and technical suitability of the developed technologies and nontechnological tools in relation to the local context is evaluated with the participation of MAC stakeholders and partners. Guidelines on economic instruments and policies for the effective implementation of the proposed water management solutions in the target MACs will be developed. Integr Environ Assess Manag 2018;14:447-462. © 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Agricultura , Reciclagem , Eliminação de Resíduos Líquidos/métodos , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Purificação da Água/métodos , Purificação da Água/estatística & dados numéricos , Egito , Marrocos , Tunísia
9.
Environ Int ; 112: 235-242, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29291449

RESUMO

Contaminated reclaimed wastewater has the potential to induce adverse effects on the health of wastewater workers and residents. However, few studies have focused on these health risks. In this study, we assessed the health risk of samples collected from different treatment processing units used in a typical water reclamation plant in Nanjing, China. Chemical analysis revealed that 40 semi-volatile organic compounds (SVOCs) and 6 N-nitrosamines (NAs) persisted after wastewater treatment. A health risk assessment revealed that the SVOCs in effluents pose negligible non-carcinogenic risk to wastewater workers and local residents as both the hazard quotient (HQ) and hazard index (HI) were all below 1.00. However, polycyclic aromatic hydrocarbons (PAHs), phthalate esters (PAEs) and NAs may present a carcinogenic risk, since their risk index via dermal exposure exceeded the safety limit (1.00×106), indicating that conventional treatment processes cannot effectively reduce the health risk in reclaimed wastewater. These results strongly suggest the need for the introduction of advanced treatment technologies capable of effectively removing SVOCs and NAs in water reclamation plants.


Assuntos
Compostos Orgânicos Voláteis/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Purificação da Água/estatística & dados numéricos , Humanos , Medição de Risco , Abastecimento de Água/normas
10.
Environ Sci Pollut Res Int ; 25(6): 5421-5436, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29209979

RESUMO

Allium cepa assay was carried out in this study to evaluate genotoxic effects of raw and treated water samples from Perak River in Perak state, Malaysia. Samples were collected from three surface water treatment plants along the river, namely WTPP, WTPS, and WTPK. Initially, triplicates of equal size Allium cepa (onions) bulbs, 25-30 mm in diameter and average weight of 20 g, were set up in distilled water for 24 h at 20 ± 2 °C and protected from direct sunlight, to let the roots to grow. After germination of roots (0.5-1.0 cm in length), bulbs were transferred to collected water samples each for a 96-h period of exposure. The root physical deformations were observed. Genotoxicity quantification was based on mitotic index and genotoxicity level. Statistical analysis using cross-correlation function for replicates from treated water showed that root length has inverse correlation with mitotic indices (r = - 0.969) and frequencies of cell aberrations (r = - 0.976) at lag 1. Mitotic indices and cell aberrations of replicates from raw water have shown positive correlation at lag 1 (r = 0.946). Genotoxicity levels obtained were 23.4 ± 1.98 (WTPP), 26.68 ± 0.34 (WTPS), and 30.4 ± 1.13 (WTPK) for treated water and 17.8 ± 0.18 (WTPP), 37.15 ± 0.17 (WTPS), and 47.2 ± 0.48 (WTPK) for raw water. The observed cell aberrations were adherence, chromosome delay, C-metaphase, chromosome loss, chromosome bridge, chromosome breaks, binucleated cell, mini cell, and lobulated nuclei. The morphogenetic deformations obtained were likely due to genotoxic substances presence in collected water samples. Thus, water treatment in Malaysia does not remove genotoxic compounds.


Assuntos
Monitoramento Ambiental , Mutagênicos/toxicidade , Cebolas/efeitos dos fármacos , Rios/química , Poluentes Químicos da Água/toxicidade , Purificação da Água/estatística & dados numéricos , Malásia , Índice Mitótico , Testes de Mutagenicidade , Cebolas/citologia , Cebolas/genética , Cebolas/crescimento & desenvolvimento , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
11.
Environ Monit Assess ; 189(11): 544, 2017 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-28988396

RESUMO

In arid environmental regions, such as the Kingdom of Saudi Arabia (KSA), each and every drop of groundwater needs to be efficiently utilized to meet growing water demands. Ground water treatment plants (WTPs) are regularly being monitored by the municipalities to ensure safe water supply. However, analyzing large data to assess the performance of a WTP has always been a daunting task for plant's management. Most of existing performance assessment frameworks were developed for surface WTPs. In this research, an assessment framework using performance-based water quality indices (P WQI) is developed to facilitate senior management of ground WTPs for effective decision-making. The framework is also implemented on a case study of Buraydah, Qassim, Saudi Arabia. Five most important water quality parameters (WQPs) have been selected to assess the performance of different components of the WTP, including raw water, pre-treatment, ultrafiltration, sand filtration, reverse osmosis, and final product. Depending on the relative importance of WQPs for a specific treatment process, different weighting schemes have been developed for each treatment process using fuzzy analytical hierarchical process (FAHP) to address the possible uncertainties in data and imprecision in expert opinion. Subsequently, fuzzy weighted sum method (FWSM) is employed to develop aggregated P WQI for assessing average monthly performance during the year 2016. Study results show that all the units consistently performed "high," and the plant is meeting drinking water quality standards throughout the year. Hypothetical scenario analysis revealed robustness of the developed framework by showing lacking performance in case failure of different units.


Assuntos
Água Subterrânea/química , Purificação da Água/métodos , Meio Ambiente , Monitoramento Ambiental , Arábia Saudita , Purificação da Água/estatística & dados numéricos , Qualidade da Água , Abastecimento de Água
12.
J Water Health ; 14(3): 513-27, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27280615

RESUMO

Water quality is an important determinant of diarrheal illnesses, especially affecting children in sub-Saharan Africa. Orphans and vulnerable children (OVC) in sub-Saharan Africa are at increased risk of poor quality drinking water, and therefore of diarrheal illness. The present study assesses primary drinking water source and typical household water purification among OVC households involved in a multi-sectoral empowerment program in semi-rural Kenya. Findings show water purification practices, but not water source, significantly increase with more time in the program. Other factors associated with safer water include household income, orphan type, food consumption and security, school completion, psychological resilience, engaging in sexual intercourse with more than one partner in the past 12 months, and previous year's financial status. Incorporating water quality improvements in a community-based empowerment program such as the one described may be one method of improving water quality and decreasing diarrheal illnesses among OVCs in sub-Saharan Africa.


Assuntos
Purificação da Água , Qualidade da Água , Adolescente , Crianças Órfãs/estatística & dados numéricos , Características da Família , Feminino , Humanos , Quênia , Masculino , População Rural , Fatores Socioeconômicos , Purificação da Água/estatística & dados numéricos , Adulto Jovem
13.
Environ Sci Pollut Res Int ; 23(18): 18055-63, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27259954

RESUMO

The project studied the occurrence, fate, and seasonal variation of 14 antibiotics, from five wastewater treatment plants (WWTPs) in Shanghai. The results indicated that ofloxacin, sulfamethoxazole, and oxytetracycline were the predominant antibiotics, with maximum concentrations of 1208.20, 959.13, and 564.30 ng/L in influents, while 916.88, 106.60, and 337.81 ng/L in effluents, respectively. The level of antibiotics in WWTPs obviously varied with seasonal changes, and higher detectable frequencies and concentrations were found in winter. The daily mass loads per capita of amoxicillin, enrofloxacin, and oxytetracycline in the study were all higher than those in other regions/countries, such as Hong Kong, Australia, and Italy. The elimination of antibiotics through these WWTPs was incomplete, and a wide range of removal efficiencies during the different treatment process and seasons were observed (-500.56 to 100 % in winter and -124.24 to 94.21 % in summer). Sulfonamides were relatively easy to be removed in WWTPs and the ultraviolet (UV) process can effectively improve the removal efficiency. Risk assessment of antibiotics in effluents was estimated. Only AMOX's hazard quotient (HQ) was higher than 0.01. Even though the environmental risks in the study were estimated to be low, the potential negative effects on aquatic ecosystems should call our attention as continually discharge in the long term.


Assuntos
Antibacterianos/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/estatística & dados numéricos , Amoxicilina/análise , China , Enrofloxacina , Monitoramento Ambiental , Fluoroquinolonas/análise , Ofloxacino/análise , Medição de Risco , Estações do Ano , Eliminação de Resíduos Líquidos
14.
J Environ Manage ; 167: 15-22, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26610194

RESUMO

In 2013, around 1336 desalination plants in the United States (US) provided purified water mainly to municipalities, the industry sector and for power generation. In 2013 alone, ∼200 million m(3) of water were desalinated; the amount that could satisfy annual municipal water consumption of more than 1.5 million people in the US. Desalination has proven to be a reliable water supply source in many countries around the world, with the total global desalination capacity of ∼60 million m(3)/day in 2013. Desalination has been used to mitigate water scarcity and lessen the pressure on water resources. Currently, data and information about desalination are still limited, while extensive socio-economic analyses are missing. This paper presents an econometric model to fill this gap. It evaluates the impact of selected socio-economic variables on desalination development in the US in the time span 1970-2013. The results show that the GDP and population growth have significantly impacted the desalination sector over the analyzed time period. The insights into the economics of desalination provided with this paper can be used to further evaluate cost-effectiveness of desalination both in the US and in other countries around the world.


Assuntos
Modelos Econométricos , Purificação da Água/métodos , Desenvolvimento Econômico , Produto Interno Bruto/estatística & dados numéricos , Humanos , Indústrias/economia , Crescimento Demográfico , Estados Unidos , Purificação da Água/estatística & dados numéricos , Abastecimento de Água/economia
15.
Biomed Res Int ; 2015: 241769, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26495290

RESUMO

To protect against the environmental pollution, the present research was undertaken to enumerate the Bacterial Technologies (BTs) on the restoration of polluted urban rivers, that is, Fenghu-Song Yang River (FSR) and Xuxi River (XXR). Experimental research accounted for the physiochemical parameters (pH; temperature; dissolved oxygen (DO); chemical oxygen demand (COD); total phosphorus (TP); total nitrogen (TN); and ammonia nitrogen (NH3N)) before and after the BT operation. The results declared that the BT is efficient to restore the polluted rivers up to reliable condition. These results were analyzed by using multivariate statistical techniques (principal component analysis (PCA) and cluster analysis (CA)). These techniques interpreted the complex data sets and expressed the point source information about the water quality of these rivers at SA5, SA6, and SB3 under highly polluted regions. For better understanding, water quality index (WQI) was applied to compute the single numeric value. WQI results are evidence of the above results which prove the water quality of both rivers faced under outrageous condition (below 50 WQI scores) before the BT treatment, but, after the treatment, the rivers were restored from fair to good level (above 50 WQI scores) and overall output of these scores was quite similar to detect the point source of pollution. These results described an abrupt recovery of the urban rivers up to reliable condition for aquatic organism and clear effluents from the rivers.


Assuntos
Fenômenos Fisiológicos Bacterianos , Reatores Biológicos/microbiologia , População Urbana/estatística & dados numéricos , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , China , Cidades , Simulação por Computador , Modelos Biológicos , Modelos Estatísticos , Medição de Risco/métodos , Purificação da Água/estatística & dados numéricos
16.
Am J Trop Med Hyg ; 93(3): 501-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26195455

RESUMO

The indicator used to measure progress toward the Millennium Development Goal (MDG) for water is access to an improved water supply. However, improved supplies are frequently fecally contaminated in developing countries. We examined factors associated with Escherichia coli contamination of improved water supplies in rural Pisco province, Peru. A random sample of 207 households with at least one child less than 5 years old was surveyed, and water samples from the source and storage container were tested for E. coli contamination. Although over 90% of households used an improved water source, 47% of source and 43% of stored water samples were contaminated with E. coli. Pouring or using a spigot to obtain water from the storage container instead of dipping a hand or object was associated with decreased risk of contamination of stored water (adjusted prevalence ratio [aPR] = 0.58, 95% confidence interval [CI] = 0.42, 0.80). Container cleanliness (aPR = 0.67, 95% CI = 0.45, 1.00) and correct handwashing technique (aPR = 0.62, 95% CI = 0.42, 0.90) were also associated with decreased contamination risk. These findings highlighted the limitations of improved water supplies as an indicator of safe water access. To ensure water safety in the home, household water treatment and improved hygiene, water handling, and storage practices should be promoted.


Assuntos
Água Potável/microbiologia , Adolescente , Adulto , Estudos Transversais , Água Potável/normas , Escherichia coli , Características da Família , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peru , População Rural , Purificação da Água/métodos , Purificação da Água/estatística & dados numéricos , Qualidade da Água/normas , Abastecimento de Água/normas , Adulto Jovem
18.
Water Sci Technol ; 69(5): 1088-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24622560

RESUMO

In Japan, membrane bioreactor (MBRs) have been installed in 17 small-scale municipal wastewater treatment plants (WWTPs) in the past 8 years, together with two recently installed MBRs for larger-scale WWTPs. In this study, design and operating data were collected from 17 of them as part of a follow-up survey, and aspects including system design, biological treatment, membrane operation, problems and costs were overviewed. Because most of the MBRs were designed according to standardized guidance, system configuration of the plants was similar; pre-denitrification using the Modified Ludzack-Ettinger (MLE) process with membrane units submerged in aerobic tanks, following a fine screen and flow equalization tank. This led to effluent quality with biochemical oxygen demand and T-N of less than 3.5 and 7.4 mg/L, respectively, for nine plants on an annual average basis. It was a common practice in extremely under-loaded plants to operate the membrane systems intermittently. Frequency of recovery cleaning events was plant-specific, mostly ranging from 1 to 5 times/year. Cost evaluation revealed that specific construction costs for the small-scale MBRs were no more than for oxidation ditch plants. Although specific energy consumption values tended to be high in the under-loaded plants, the demonstration MBR, where several energy reducing measures had been incorporated, attained specific energy consumption of 0.39 kWh/m(3) under full-capacity operation.


Assuntos
Reatores Biológicos/estatística & dados numéricos , Purificação da Água/instrumentação , Japão , Membranas Artificiais , Purificação da Água/economia , Purificação da Água/estatística & dados numéricos
19.
Environ Pollut ; 187: 193-201, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24521932

RESUMO

With the rapid economic development, a better living condition leads to longer life expectancy, which increased the total population, in particular the elderly group. It may result in increase in the demand of pharmaceuticals for people in domestic use or in hospital. Although most sewage treatment plants or waste water treatment plantsmet the regulatory requirement, there are still many pharmaceuticals removed incompletely and thus discharged to the environment. Therefore, the pharmaceuticals residue draws the public concern because they might cause adverse effects on the organism even human beings. Recently, many studies have published on the source and occurrence as well as the fate of pharmaceuticals all over the world. This paper summarized and reviewed the recent studies on the sources, occurrence, fate and the effects of the most common pharmaceuticals. Finally, it gave the suggestion and risk management for controlling the pharmaceuticals.


Assuntos
Preparações Farmacêuticas/análise , Poluentes do Solo/análise , Solo/química , Poluentes Químicos da Água/análise , Meio Ambiente , Humanos , Poluição Química da Água/estatística & dados numéricos , Purificação da Água/estatística & dados numéricos
20.
Environ Sci Technol ; 48(3): 1582-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24417368

RESUMO

A parallel factor (PARAFAC) analysis approach was used to study the character and composition of dissolved organic matter (DOM) in a multicoagulant (two aluminum-based coagulants) full scale drinking water treatment plant. A three year, long-term assessment was conducted based on deconstruction of the excitation-emission matrices (EEM) of over 1000 water samples collected before and after parallel coagulation treatment basins. Two humic moieties and a protein-like group were identified in the raw and treated waters. Apportionment of fluorophores was established using a novel approach based on the overall fluorescence intensity (OFI) of PARAFAC components. Uncorrected matrix correlation (UMC) revealed minimal changes of the fluorescence moieties after treatment (UMC > 0.98), and a comparable effect of both coagulants on the structure (UMC > 0.99) and distribution of these groups. Coagulation increased the proportion of the protein-like fluorophore and preferentially removed a humic-like group irrespective of the coagulant. Preference for this moiety was supported by a coagulant-affinity factor derived from the association between PARAFAC components after treatment. The suitability of a PARAFAC-based approach for coagulant evaluation/selection was demonstrated when compared to a dissolved organic carbon (DOC)-based criterion. This paper contributes to the understanding of the behavior of PARAFAC components in water treatment processes and presents several approaches for the future monitoring and control of coagulation at full scale treatment facilities.


Assuntos
Compostos de Alúmen/química , Hidróxido de Alumínio/química , Água Potável/análise , Substâncias Húmicas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Água Potável/normas , Análise Fatorial , Floculação , Espectrometria de Fluorescência/métodos , Espectrometria de Fluorescência/estatística & dados numéricos , Purificação da Água/estatística & dados numéricos
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