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Fluence-based QMRA model for bacterial photorepair and regrowth in drinking water after decentralized UV disinfection. WATER RESEARCH 2023; 231:119612. [PMID: 36706469 DOI: 10.1016/j.watres.2023.119612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 12/19/2022] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Ultraviolet disinfection is a promising solution for decentralized drinking water systems such as communal water taps. A potential health risk is enzymatic photorepair of pathogens after UV disinfection, which can result in regrowth of pathogens. Even though photorepair is a known issue, no formal risk assessments have been conducted for photorepair after UV disinfection in drinking water. The main objective was to construct a quantitative microbial risk assessment (QMRA) of photorepair after UV disinfection of drinking water in a decentralized system. UV disinfection and photorepair kinetics for E. coli were modelled using reproducible fluence-based determinations. Impacts of water collection patterns, and wavelength-dependent water container material transmittance, sunlight intensity, and photorepair enzyme absorbance were quantified. After UV disinfection by 16 or 40 mJ/cm2 of < 5-log microorganisms per L, risk of infection did not exceed 1-in-10,000 under conditions permitting E. coli photorepair. Risk from photorepair was less than 1-in-10,000 for photorepair light exposure < 0.75 h throughout the day for UV fluence 16 mJ/cm2 or greater. UV disinfection followed by solar disinfection surpassing photoreactivation during storage reduced risk below 1-in-10,000 for photorepair light exposure > 2.5 h between modelled times of 9 AM - 3 PM. The model can be expanded to other pathogens as UV fluence and photorepair fluence response kinetics become available, and this QMRA can be used to inform the placement of community water access points to reduce risk of photorepair and ensure adequate shelf life of UV disinfected water under safe storage conditions.
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Measured and Modeled Comparisons of Chemical and Microbial Contaminants in Tap and Bottled Water in a US-Mexico Border Community. ACS ES&T WATER 2022; 2:2657-2667. [PMID: 37810444 PMCID: PMC10552926 DOI: 10.1021/acsestwater.2c00400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Tap water quality concerns and advertisements often drive increased bottled water consumption, especially in communities with historical tap water quality problems (e.g., Nogales, Arizona). The study objective was to assess contamination of municipal tap and bottled water in Nogales, Arizona. Bottled (sealed, open/partially consumed bottles, and reusable containers for vended water) and tap water samples were collected from 30 homes and analyzed for chemical and microbial contaminants. Fisher exact tests and Wilcoxon rank sum tests were used to compare proportions of positive samples and contaminant concentrations between tap and bottled water samples. While none of the chemical contaminants were above MCLs, there were statistically significantly greater concentrations and proportions of positive samples for some contaminants, including arsenic, in tap vs. bottled water. E. coli concentrations were >0 CFU/100mL in some unsealed bottled water samples but not for sealed bottles. This study demonstrates that 1) the measured concentrations in tap and bottled water likely pose low risks, as they are below the MCLs, 2) more education in this community on hygiene maintenance of refillable or opened bottled water containers is needed, and 3) using tap water over bottled water is advantageous due to likely lower E. coli risk and lower cost.
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Evaluation of plastic packaged water quality using health risk indices: A case study of sachet and bottled water in Accra, Ghana. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 832:155073. [PMID: 35398415 DOI: 10.1016/j.scitotenv.2022.155073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/27/2022] [Accepted: 04/02/2022] [Indexed: 06/14/2023]
Abstract
Plastic packaged water is the drinking water of choice for urban populations across Africa but its quality remains questionable in most developing countries. Six hundred (600) packages, consisting of sachet and bottled water, were sampled from two high-end companies in Accra (Ghana) and stored through their shelf lives under an average room temperature of 30 °C. The samples were tested for physicochemical quality and the presence of bacteria and phthalate esters at 2n × 3 periods, where n is the sampled batch number. The data were described and modelled with embedded Bayesian and Machine Learning algorithms in JASP0.16.0.0 and Argo-4.1.3. The results reported lower than regulated levels of electrical conductivity (163.66 μS/cm), alkalinity (39.67 mg/L), and residual chlorine (<0.01 mg/L) while the pH was generally within specification (6.5-7.7). All samples showed progressive biological contamination following the third week (sachet samples) and the sixth week (bottled water) of incubation. Initial samples, including raw water, processed bulk water and packaged water did not present detectable microbial growth. The total microbial load in sachet samples grew at 0.936 cfu/week and 1.006 cfu/week for the bottled samples although the results did not exceed 1000 cfu/L (0-976 cfu/100 mL). Modelled mean probability of infection was 1.196 × 10-4 in 67% of the samples. Raw and processed water samples did not show detectable levels of phthalate contaminants. The mean hazard index calculated on the individual hazard quotients of phthalates was 7.41 × 10-3 ± 8.20 × 10-4, suggesting lower acute risk potential. Mean integrated lifetime cancer risk (ILCR) was determined to be 1.53 × 10-3 ± 1.71 × 10-4 within a range of 2.86 × 10-4 and 7.18 × 10-3. Mean child ILCR was about 70% of adult ILCR and increased from 4.16 × 10-4 to 2.41 × 10-3 for sachet and 4.93 × 10-4 to 7.18 × 10-3 for bottled water. For adult ILCR, sachet water presented 2.86 × 10-4 to 1.65 × 10-3, and 3.38 × 10-4 to 4.93 × 10-3 for bottled water. This study confirmed the presence of phthalates and pathogenic bacteria in the samples, at-risk levels that require mitigation.
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Bottled and Well Water Quality in a Small Central Appalachian Community: Household-Level Analysis of Enteric Pathogens, Inorganic Chemicals, and Health Outcomes in Rural Southwest Virginia. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148610. [PMID: 35886462 PMCID: PMC9319903 DOI: 10.3390/ijerph19148610] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 02/05/2023]
Abstract
Consumption of unsafe drinking water is associated with a substantial burden of disease globally. In the US, ~1.8 million people in rural areas lack reliable access to safe drinking water. Our objective was to characterize and assess household-level water sources, water quality, and associated health outcomes in Central Appalachia. We collected survey data and water samples (tap, source, and bottled water) from consenting households in a small rural community without utility-supplied water in southwest Virginia. Water samples were analyzed for physicochemical parameters, total coliforms, E. coli, nitrate, sulfate, metals (e.g., arsenic, cadmium, lead), and 30+ enteric pathogens. Among the 69% (n = 9) of households that participated, all had piped well water, though 67% (n = 6) used bottled water as their primary drinking water source. Total coliforms were detected in water samples from 44.4% (n = 4) of homes, E. coli in one home, and enteric pathogens (Aeromonas, Campylobacter, Enterobacter) in 33% (n = 3) of homes. Tap water samples from 11% (n = 1) of homes exceeded the EPA MCL for nitrate, and 33% (n = 3) exceeded the EPA SMCL for iron. Among the 19 individuals residing in study households, reported diarrhea was 25% more likely in homes with measured E. coli and/or specific pathogens (risk ratio = 1.25, cluster-robust standard error = 1.64, p = 0.865). Although our sample size was small, our findings suggest that a considerable number of lower-income residents without utility-supplied water in rural areas of southwest Virginia may be exposed to microbiological and/or chemical contaminants in their water, and many, if not most, rely on bottled water as their primary source of drinking water.
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Sachet water in Ghana: A spatiotemporal analysis of the recent upward trend in consumption and its relationship with changing household characteristics, 2010-2017. PLoS One 2022; 17:e0265167. [PMID: 35617289 PMCID: PMC9135223 DOI: 10.1371/journal.pone.0265167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 02/24/2022] [Indexed: 12/01/2022] Open
Abstract
The consumption of packaged water in Ghana has grown significantly in recent years. By 2017, "sachet water"-machine-sealed 500ml plastic bags of drinking water-was consumed by 33% of Ghanaian households. Reliance on sachet water has previously been associated with the urban poor, yet recent evidence suggests a customer base which crosses socioeconomic lines. Here, we conduct a repeated cross-sectional analysis of three nationally representative datasets to examine the changing demography of sachet water consumers between 2010 and 2017. Our results show that over the course of the study period sachet water has become a ubiquitous source of drinking water in Ghana, with relatively wealthy households notably increasing their consumption. In 2017, the majority of sachet water drinking households had access to another improved water source. The current rate and form of urbanisation, inadequate water governance, and an emphasis on cost recovery pose significant challenges for the expansion of the piped water supply network, leading us to conclude that sachet water will likely continue to be a prominent source of drinking water in Ghana for the foreseeable future. The main challenge for policymakers is to ensure that the growing sachet water market enhances rather than undermines Ghana's efforts towards achieving universal and equitable access to clean drinking water and sanitation.
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Health and environmental impacts of drinking water choices in Barcelona, Spain: A modelling study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 795:148884. [PMID: 34247071 DOI: 10.1016/j.scitotenv.2021.148884] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/16/2021] [Accepted: 07/03/2021] [Indexed: 06/13/2023]
Abstract
Quantitative evidence of health and environmental tradeoffs between individuals' drinking water choices is needed to inform decision-making. We evaluated health and environmental impacts of drinking water choices using health impact and life cycle assessment (HIA, LCA) methodologies applied to data from Barcelona, Spain. We estimated the health and environmental impacts of four drinking water scenarios for the Barcelona population: 1) currently observed drinking water sources; a complete shift to 2) tap water; 3) bottled water; or 4) filtered tap water. We estimated the local bladder cancer incidence attributable to trihalomethane (THM) exposure, based on survey data on drinking water sources, THM levels, published exposure-response functions, and disability-adjusted life years (DALYs) from the Global Burden of Disease 2017. We estimated the environmental impacts (species lost/year, and resources use) from waste generation and disposal, use of electricity, chemicals, and plastic to produce tap or bottled drinking water using LCA. The scenario where the entire population consumed tap water yielded the lowest environmental impact on ecosystems and resources, while the scenario where the entire population drank bottled water yielded the highest impacts (1400 and 3500 times higher for species lost and resource use, respectively). Meeting drinking water needs using bottled or filtered tap water led to the lowest bladder cancer DALYs (respectively, 140 and 9 times lower than using tap water) in the Barcelona population. Our study provides the first attempt to integrate HIA and LCA to compare health and environmental impacts of individual water consumption choices. Our results suggest that the sustainability gain from consuming water from public supply relative to bottled water may exceed the reduced risk of bladder cancer due to THM exposure from consuming bottled water in Barcelona. Our analysis highlights several critical data gaps and methodological challenges in quantifying integrated health and environmental impacts of drinking water choices.
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Abstract
OBJECTIVES About 18% of urban households in Nigeria depend on packaged sachet water as the primary source of drinking water. This review assessed microbial contamination of these products with an emphasis on total coliforms and the faecal indicator bacteria (FIB) - Escherichia coli (E. coli) and thermotolerant coliforms (TTC). METHODS PubMed/Medline, African Index Medicus, AfroLib, Global Health Library, Embase and the ISI Web of Science databases were searched to identify original research published up to October 2020. The literature findings were synthesised narratively in line with the review objectives. To assess prevalence of microbial contamination, a random effects meta-analysis, was also conducted using the R metafor package in RStudio. The protocol for this review is registered on PROSPERO with reference number CRD 42019128474. RESULTS Fifty-two of 429 studies were identified for inclusion. At 53.27%, contamination prevalence was higher for total coliforms (95% CI: 39.05-66.98, I2 = 81%, p < 0.01, 42 studies) than FIB (12.38%, 95% CI: 7.92-18.85, I2 = 61%, p < 0.01, 33 studies) suggesting that treatment failure is a major contributor to the poor microbial quality reported in the included studies. Within the FIB group, the prevalence of contamination with E. coli was 13.30% (95% CI: 8.23-20.80, I2 = 65%, p < 0.01, 27 studies) versus 6.24% (95% CI: 1.12-28.06, I2 = 72%, p < 0.01, six studies) for TTCs. Other microbial contaminants reported were Pseudomonas aeruginosa, Klebsiella and Enterococcus faecalis and these showed multidrug antibiotic resistance. CONCLUSIONS The findings of this review highlight the need for improved regulatory oversight with more stringent monitoring of the microbial quality of sachet water products in Nigeria.
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Abstract
Drinking water in Ghana is estimated at 79%, but this only represents the proportion of the population with access to improved drinking water sources without regard to the quality of water consumed. This study investigated the quality of household drinking water sources in the Oforikrom municipality where potable water requirements are on the rise due to an ever-increasing population. Both quantitative and qualitative methods were employed in this study. One Hundred households were randomly selected and interviewed on the available options for drinking water and household water treatment and safe storage. A total of 52 points of collection (POC) and 97 points of use (POU) water samples from households were collected for physicochemical and microbial water quality analysis. Amongst the available drinking water options, sachet water (46%) was mostly consumed by households. Water quality analysis revealed that the physicochemical parameters of all sampled drinking water sources were within the Ghana Standards Authority (GSA) recommended values expected for pH (ranging from 4.50 to 7.50). For the drinking water sources, bottled (100%, n = 2) and sachet water (91%, n = 41) showed relatively good microbial water quality. Generally, POC water samples showed an improved microbial water quality in comparison to POU water samples. About 38% (n = 8) of the households practicing water quality management, were still exposed to unsafe drinking water sources. Households should practice good water quality management at the domestic level to ensure access to safe drinking water. This may include the use of chlorine-based disinfectants to frequently disinfect boreholes, wells and storage facilities at homes.
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Fecal Indicator Bacteria Data to Characterize Drinking Water Quality in Low-Resource Settings: Summary of Current Practices and Recommendations for Improving Validity. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18052353. [PMID: 33670869 PMCID: PMC7957662 DOI: 10.3390/ijerph18052353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/14/2021] [Accepted: 02/20/2021] [Indexed: 11/16/2022]
Abstract
Fecal indicator bacteria (FIB) values are widely used to assess microbial contamination in drinking water and to advance the modeling of infectious disease risks. The membrane filtration (MF) testing technique for FIB is widely adapted for use in low- and middle-income countries (LMICs). We conducted a systematic literature review on the use of MF-based FIB data in LMICs and summarized statistical methods from 172 articles. We then applied the commonly used statistical methods from the review on publicly available datasets to illustrate how data analysis methods affect FIB results and interpretation. Our findings indicate that standard methods for processing samples are not widely reported, the selection of statistical tests is rarely justified, and, depending on the application, statistical methods can change risk perception and present misleading results. These results raise concerns about the validity of FIB data collection, analysis, and presentation in LMICs. To improve evidence quality, we propose a FIB data reporting checklist to use as a reminder for researchers and practitioners.
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Abstract
Background: The demand for drinking water has necessitated the proliferation of bottled water companies in Kenya. This study evaluated if retailed bottled water in Nairobi Kenya complies with both local and international reference criteria. Methods: A total of 42 different water brands (25 approved by Kenya Revenue Authority (KRA) and 17 banned brands) were analyzed for both physicochemical and bacteriological quality. The spread plate method was used to obtain the total plate count of bacteria, while the membrane filter method was used to obtain total coliform count (TCC) and fecal coliform count (FCC). Structured interviews were used to gather company-related information. Results: Overall, 16% of KRA-approved and 35.3% of banned bottled water were contaminated with heterotrophic bacteria. Of the approved water brands, 4% were positive for total coliforms, compared with 17% of the banned brands. Similarly, 4% and 17% approved and banned water brands were positive for fecal coliforms, respectively. Escherichia coli (19.1%), Pseudomonas spp. (9.5%) and Klebsiella spp. (4.8%) were the most common bacterial types isolated from all water brands, most of which exhibited multidrug resistance. In multivariable analysis, water companies that cleaned pipework and bottles using chlorine-based disinfectants (OR 0.08, 95% CI 0.01 to 0.8), those that had food safety programs (OR 0.1, 95% CI 0.019 to 0.9), had standard operating procedures (SOP) for water sourcing (OR 0.1, 95% CI 0.012 to 0.9) and SOP for contamination protection (OR 0.1, 95% CI 0.02 to 0.9) remained independently associated with bottled water brands exceeding WHO TCC limits. Conclusions: A number of bottled water brands were contaminated with one or more types of indicator bacteria, some of which were multidrug-resistant. Water bottling companies' processes contribute to contamination. Rigorous regulation and monitoring will improve water quality and safety.
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Bottled water brands are contaminated with multidrug resistant bacteria in Nairobi, Kenya. F1000Res 2020; 9:1337. [PMID: 33796276 PMCID: PMC7970434 DOI: 10.12688/f1000research.24031.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/26/2021] [Indexed: 11/20/2022] Open
Abstract
Background: The demand for drinking water has necessitated the proliferation of bottled water companies in Kenya. This study evaluated if retailed bottled water in Nairobi Kenya complies with both local and international reference criteria. Methods: A total of 42 different water brands (25 approved by Kenya Revenue Authority (KRA) and 17 banned brands) were analyzed for both physicochemical and bacteriological quality. The spread plate method was used to obtain the total plate count of bacteria, while the membrane filter method was used to obtain total coliform count (TCC) and fecal coliform count (FCC). Structured interviews were used to gather company-related information. Results: Overall, 16% of KRA-approved and 35.3% of banned bottled water were contaminated with heterotrophic bacteria. Of the approved water brands, 4% were positive for total coliforms, compared with 17% of the banned brands. Similarly, 4% and 17% approved and banned water brands were positive for fecal coliforms, respectively.
Escherichia coli (19.1%),
Pseudomonas spp. (9.5%) and
Klebsiella spp. (4.8%) were the most common bacterial types isolated from all water brands, most of which exhibited multidrug resistance. In multivariable analysis, water companies that cleaned pipework and bottles using chlorine-based disinfectants (OR 0.08, 95% CI 0.01 to 0.8), those that had food safety programs (OR 0.1, 95% CI 0.019 to 0.9), had standard operating procedures (SOP) for water sourcing (OR 0.1, 95% CI 0.012 to 0.9) and SOP for contamination protection (OR 0.1, 95% CI 0.02 to 0.9) remained independently associated with bottled water brands exceeding WHO TCC limits. Conclusions: A number of bottled water brands were contaminated with one or more types of indicator bacteria, some of which were multidrug-resistant. Water bottling companies’ processes contribute to contamination. Rigorous regulation and monitoring will improve water quality and safety.
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Application of a Faecalibacterium 16S rDNA genetic marker for species identification of dog fecal waste. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:30615-30624. [PMID: 32472511 DOI: 10.1007/s11356-020-09369-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 05/19/2020] [Indexed: 06/11/2023]
Abstract
A dog-associated 16S rDNA genetic marker (ED-1) was designed to detect dog fecal contamination in water through a comparative bioinformatics analysis of Faecalibacterium sequences. For the dog fecal samples, ED-1 had 100% specificity, a high positive rate (89% in dog feces and 92.3% in dog fecal-contaminated water samples), and a low detection limit (107 copies/100 mL) in dog-contaminated water samples. Detection of water samples from seven provinces or cities of China showed that ED-1 was stable enough to be applied in practice. Furthermore, the abundance and diversity of dog gut microbiota from two private house pets (PHP) and Third Military Medical University (TMMU) dogs were estimated by using operational taxonomic units, and the significant differences of dog feces were found, as the PHP dogs have a more diverse diet and closer contact with human than dogs in TMMU. However, ED-1 could detect the feces from the two regions, indicating that ED-1 has good reliability.
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Dual-Functional, Superhydrophobic Coatings with Bacterial Anticontact and Antimicrobial Characteristics. ACS APPLIED MATERIALS & INTERFACES 2020; 12:21311-21321. [PMID: 32023023 DOI: 10.1021/acsami.9b18928] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Bacterial pathogens are responsible for millions of cases of illnesses and deaths each year throughout the world. The development of novel surfaces and coatings that effectively inhibit and prevent bacterial attachment, proliferation, and growth is one of the crucial steps for tackling this global challenge. Herein, we report a dual-functional coating for aluminum surfaces that relies on the controlled immobilization of lysozyme enzyme (muramidase) into interstitial spaces of presintered, nanostructured thin film based on ∼200 nm silica nanoparticles and the sequential chemisorption of an organofluorosilane to the available interfacial areas. The mean diameter of the resultant lysozyme microdomains was 3.1 ± 2.5 μm with an average spacing of 8.01 ± 6.8 μm, leading to a surface coverage of 15.32%. The coating had an overall root-mean-square (rms) roughness of 539 ± 137 nm and roughness factor of 1.50 ± 0.1, and demonstrated static, advancing, and receding water contact angles of 159.0 ± 1.0°, 155.4 ± 0.6°, and 154.4 ± 0.6°, respectively. Compared to the planar aluminum, the coated surfaces produced a 6.5 ± 0.1 (>99.99997%) and 4.0 ± 0.1 (>99.99%) log-cycle reductions in bacterial surfaces colonization against Gram-negative Salmonella Typhimurium LT2 and Gram-positive Listeria innocua, respectively. We anticipate that the implementation of such a coating strategy on healthcare environments and surfaces and food-contact surfaces can significantly reduce or eliminate potential risks associated with various contamination and cross-contamination scenarios.
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Groundwater as a Source of Drinking Water in Southeast Asia and the Pacific: A Multi-Country Review of Current Reliance and Resource Concerns. WATER 2019. [DOI: 10.3390/w11081605] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Groundwater is widely acknowledged to be an important source of drinking water in low-income regions, and it, therefore, plays a critical role in the realization of the human right to water. However, the proportion of households using groundwater compared with other sources is rarely quantified, with national and global datasets more focused on facilities—rather than resources—used. This is a significant gap in knowledge, particularly in light of efforts to expand water services in line with the inclusive and integrated agenda of the Sustainable Development Goals. Understanding the prevalence of groundwater reliance for drinking is critical for those involved in water services planning and management, so they can better monitor and advocate for management of water resources that supports sustainable services for households. This paper contributes data that can be used to strengthen the integration of resource considerations within water service delivery and inform the work of development partners supporting this area. We approach this issue from two perspectives. Firstly, we collate data on the proportion of households using groundwater as their primary drinking water source for 10 Southeast Asian and Pacific nations, finding an average of 66% (range of 17–93% for individual countries) of households in urban areas and 60% (range of 22–95%) of households in rural areas rely on groundwater for drinking. Together, these constitute 79% of the total population across the case study countries. Secondly, we review current and emerging groundwater resource concerns within each country, using a systems thinking approach to assess how groundwater resource issues influence household water services. Findings support the case for governments and development agencies to strengthen engagement with groundwater resource management as foundational for achieving sustainable water services for all.
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Burden of disease from inadequate water, sanitation and hygiene for selected adverse health outcomes: An updated analysis with a focus on low- and middle-income countries. Int J Hyg Environ Health 2019; 222:765-777. [PMID: 31088724 PMCID: PMC6593152 DOI: 10.1016/j.ijheh.2019.05.004] [Citation(s) in RCA: 217] [Impact Index Per Article: 43.4] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 05/03/2019] [Accepted: 05/03/2019] [Indexed: 12/11/2022]
Abstract
Background To develop updated estimates in response to new exposure and exposure-response data of the burden of diarrhoea, respiratory infections, malnutrition, schistosomiasis, malaria, soil-transmitted helminth infections and trachoma from exposure to inadequate drinking-water, sanitation and hygiene behaviours (WASH) with a focus on low- and middle-income countries. Methods For each of the analysed diseases, exposure levels with both sufficient global exposure data for 2016 and a matching exposure-response relationship were combined into population-attributable fractions. Attributable deaths and disability-adjusted life years (DALYs) were estimated for each disease and, for most of the diseases, by country, age and sex group separately for inadequate water, sanitation and hygiene behaviours and for the cluster of risk factors. Uncertainty estimates were computed on the basis of uncertainty surrounding exposure estimates and relative risks. Findings An estimated 829,000 WASH-attributable deaths and 49.8 million DALYs occurred from diarrhoeal diseases in 2016, equivalent to 60% of all diarrhoeal deaths. In children under 5 years, 297,000 WASH-attributable diarrhoea deaths occurred, representing 5.3% of all deaths in this age group. If the global disease burden from different diseases and several counterfactual exposure distributions was combined it would amount to 1.6 million deaths, representing 2.8% of all deaths, and 104.6 million DALYs in 2016. Conclusions Despite recent declines in attributable mortality, inadequate WASH remains an important determinant of global disease burden, especially among young children. These estimates contribute to global monitoring such as for the Sustainable Development Goal indicator on mortality from inadequate WASH.
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Towards A Situated Urban Political Ecology Analysis of Packaged Drinking Water Supply. WATER 2019. [DOI: 10.3390/w11020225] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The inclusion of packaged drinking water (PDW) as a potentially improved source of safe drinking water under Goal 6.1 of the Sustainable Development Goals (SDG) reflects its growing significance in cities where piped water has never been universal or safe for drinking. Using the case of PDW in Jakarta, Indonesia, we call for theorizing the politics of PDW through a situated Urban Political Ecology (UPE) analysis of the wider urban water distributions in which it is inserted. We do so in order to interrogate the unevenness of individual “choices” for securing safe drinking water, and highlight the ambiguity of PDW’s impact on inequalities in access. We first review research on PDW supply to specify how dominant theoretical approaches used for understanding PDW supply through analyses of the individual making “choices” for drinking water are power neutral, and why this matters for achieving equitable water access. We illustrate these points through a case study of PDW consumption by low income residents in Jakarta, and then identify how a situated UPE framework can help attend to the uneven societal relations shaping different socio-material conditions, within which individual “choices” for PDW are made. For Jakarta, connecting choices of the individual to power relations shaping geographies of urban water access and risk explains the rise in PDW consumption by low income residents as a situated response to the uneven exposure of poorer residents to environmental hazards. We conclude with reflections on how this can inform interventions towards more just distributions of safe drinking water.
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Consumer perceptions and purchasing of packaged water products in Sierra Leone. Pan Afr Med J 2019; 30:262. [PMID: 30637047 PMCID: PMC6317298 DOI: 10.11604/pamj.2018.30.262.13676] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 07/10/2018] [Indexed: 11/18/2022] Open
Abstract
Introduction Access to improved sources of drinking water remains a complex challenge in Sierra Leone and other low and middle income countries. We aimed to qualitatively examine consumer perceptions and purchasing behaviors of packaged water products in Sierra Leone. Methods We conducted 25 focus groups with 178 consumers and petty traders of packaged water across the four geographic regions of Sierra Leone. Discussions were recorded, transcribed, and coded into themes. The Health Belief Model guided the thematic data analysis. Results Packaged water was broadly perceived as safe, accessible, and convenient. Participants who lived outside of the capital city, Freetown, were more likely to report cost as a barrier. Personal experiences with a brand moderated trust levels. Self-reported handling behaviors of PW products were generally unhygienic. There was widespread belief that packaged water keeps newborn babies healthy. Consumers desired a simple mechanism to better identify government approved PW products. Conclusion Perceived risks, benefits, barriers, self-efficacy, and reinforcing cues to action qualitatively influenced consumers’ purchasing behavior of packaged water. Government regulators should provide consumers with reliable means to identify approved packaged water products. Consumer education efforts should include hygienic handling of packaged water products in order to minimize post-production contamination.
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An Evolving Choice in a Diverse Water Market: A Quality Comparison of Sachet Water with Community and Household Water Sources in Ghana. Am J Trop Med Hyg 2018; 99:526-533. [PMID: 29893206 PMCID: PMC6090358 DOI: 10.4269/ajtmh.17-0804] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 02/28/2018] [Indexed: 11/07/2022] Open
Abstract
Packaged water, particularly bagged sachet water, has become an important drinking water source in West Africa as local governments struggle to provide safe drinking water supplies. In Ghana, sachet water has become an important primary water source in urban centers, and a growing literature has explored various dimensions of this industry, including product quality. There is very little data on sachet water quality outside of large urban centers, where smaller markets often mean less producer competition and less government regulation. This study analyzes the microbiological quality of sachet water alongside samples of other common water sources at point-of-collection (POC) and point-of-use (POU) in 42 rural, peri-urban, and small-town Ghanaian communities using the IDEXX Colilert® 18 (Westbrook, ME). Levels of coliform bacteria and Escherichia coli detected in sachet water samples were statistically and significantly lower than levels detected in all other water sources at POU, including public taps and standpipes, and statistically similar or significantly lower at POC. In diverse waterscapes where households regularly patch together their water supply from different sources, sachet water appears to be an evolving alternative for safe drinking water despite many caveats, including higher unit costs and limited opportunities to recycle the plastic packaging.
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Impact of drinking water, sanitation and handwashing with soap on childhood diarrhoeal disease: updated meta-analysis and meta-regression. Trop Med Int Health 2018. [PMID: 29537671 DOI: 10.1111/tmi.13051] [Citation(s) in RCA: 187] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVES Safe drinking water, sanitation and hygiene are protective against diarrhoeal disease; a leading cause of child mortality. The main objective was an updated assessment of the impact of unsafe water, sanitation and hygiene (WaSH) on childhood diarrhoeal disease. METHODS We undertook a systematic review of articles published between 1970 and February 2016. Study results were combined and analysed using meta-analysis and meta-regression. RESULTS A total of 135 studies met the inclusion criteria. Several water, sanitation and hygiene interventions were associated with lower risk of diarrhoeal morbidity. Point-of-use filter interventions with safe storage reduced diarrhoea risk by 61% (RR = 0.39; 95% CI: 0.32, 0.48); piped water to premises of higher quality and continuous availability by 75% and 36% (RR = 0.25 (0.09, 0.67) and 0.64 (0.42, 0.98)), respectively compared to a baseline of unimproved drinking water; sanitation interventions by 25% (RR = 0.75 (0.63, 0.88)) with evidence for greater reductions when high sanitation coverage is reached; and interventions promoting handwashing with soap by 30% (RR = 0.70 (0.64, 0.77)) vs. no intervention. Results of the analysis of sanitation and hygiene interventions are sensitive to certain differences in study methods and conditions. Correcting for non-blinding would reduce the associations with diarrhoea to some extent. CONCLUSIONS Although evidence is limited, results suggest that household connections of water supply and higher levels of community coverage for sanitation appear particularly impactful which is in line with targets of the Sustainable Development Goals.
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A systematic review of nosocomial waterborne infections in neonates and mothers. Int J Hyg Environ Health 2017; 220:1199-1206. [DOI: 10.1016/j.ijheh.2017.07.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/31/2017] [Accepted: 07/31/2017] [Indexed: 11/24/2022]
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Predictors of Drinking Water Boiling and Bottled Water Consumption in Rural China: A Hierarchical Modeling Approach. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:6945-6956. [PMID: 28528546 DOI: 10.1021/acs.est.7b01006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Approximately two billion people drink unsafe water. Boiling is the most commonly used household water treatment (HWT) method globally and in China. HWT can make water safer, but sustained adoption is rare and bottled water consumption is growing. To successfully promote HWT, an understanding of associated socioeconomic factors is critical. We collected survey data and water samples from 450 rural households in Guangxi Province, China. Covariates were grouped into blocks to hierarchically construct modified Poisson models and estimate risk ratios (RR) associated with boiling methods, bottled water, and untreated water. Female-headed households were most likely to boil (RR = 1.36, p < 0.01), and among boilers those using electric kettles rather than pots had higher income proxies (e.g., per capita TV ownership RR = 1.42, p < 0.01). Higher-income households with younger, literate, and male heads were more likely to purchase (frequently contaminated) bottled water, or use electric kettles if they boiled. Our findings show that boiling is not an undifferentiated practice, but one with different methods of varying effectiveness, environmental impact, and adoption across socioeconomic strata. Our results can inform programs to promote safer and more efficient boiling using electric kettles, and suggest that if rural China's economy continues to grow then bottled water use will increase.
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Seasonal Variation in Drinking and Domestic Water Sources and Quality in Port Harcourt, Nigeria. Am J Trop Med Hyg 2016; 96:437-445. [PMID: 27821689 DOI: 10.4269/ajtmh.16-0175] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 09/23/2016] [Indexed: 11/07/2022] Open
Abstract
We compared dry and rainy season water sources and their quality in the urban region of Port Harcourt, Nigeria. Representative sampling indicated that municipal water supplies represent < 1% of the water sources. Residents rely on privately constructed and maintained boreholes that are supplemented by commercially packaged bottled and sachet drinking water. Contamination by thermotolerant coliforms increased from 21% of drinking water sources in the dry season to 42% of drinking water sources in the rainy season (N = 356 and N = 397). The most significant increase was in sachet water, which showed the lowest frequencies of contamination in the dry season compared with other sources (15%, N = 186) but the highest frequencies during the rainy season (59%, N = 76). Only half as many respondents reported drinking sachet water in the rainy season as in the dry season. Respondents primarily used flush or pour-flush toilets connected to septic tanks (85%, N = 399). The remainder relied on pit latrines and hanging (pier) latrines that drained into surface waters. We found significant associations between fecal contamination in boreholes and the nearby presence of hanging latrines. Sanitary surveys of boreholes showed that more than half were well-constructed, and we did not identify associations between structural or site deficiencies and microbial water quality. The deterioration of drinking water quality during the rainy season is a serious public health risk for both untreated groundwater and commercially packaged water, highlighting a need to address gaps in monitoring and quality control.
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