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Implications of Bottled Water Use in Rural Central AppalachiaAlbi, Kate Nicole 21 May 2024 (has links)
An increasing number of Americans identify bottled water as their preferred water source to meet household needs, despite additional expenses and less stringent quality reporting requirements. Previous studies note perceptions of poor water quality and/or distrust in public water authorities as the primary drivers of bottled water use. Examinations of Safe Drinking Water Act (SDWA) violation data validate these perceptions and highlight the increased prevalence of drinking water disparities in rural, low-income communities. This effort aims to assess in-home and bottled drinking water throughout rural Central Appalachia: a documented water inequity hotspot.
To evaluate the uses, perceptions, motivations, expenditures, and quality related to in-home and bottled water sources, 24 homes in three different Central Appalachian counties were recruited to complete household surveys. Concurrently, 23 in-home (11 municipally and 12 privately sourced), 11 brands of bottled water, and four roadside spring samples identified as preferred drinking water sources were collected and analyzed for regulated (bacteria, inorganic ions) and emerging (per-and polyfluoroalkyl substances (PFAS), microplastics) contaminants via Standard Methods and compared to Safe Drinking Water Act (SDWA) standards (if applicable).
The majority of respondents viewed their in-home water quality as satisfactory or less due to negative organoleptic perceptions (taste, odor, appearance). In-home and roadside spring water quality generally aligned with poor perceptions: coliform bacteria, E. coli, aluminum, iron, manganese, and sodium were detected at concentrations above United States Environmental Protection Agency (USEPA) standards and guidelines. Approximately 71 percent of homes reported bottled water as their primary drinking water source. Bottled water samples did not exceed any USEPA health-based regulations. The presence of inorganic ions contaminants varied greatly across the 11 brands of bottled water assessed, and within brand variability was noted in one bottled water brand purchased at two different locations. PFAS compounds were detected in both in-home and bottled water samples, though at relatively low levels. Microplastic particles were found in all samples, regardless of source. Statistical analyses revealed significantly higher concentrations of all contaminants in point-of-use samples compared to bottled water, except total microplastic particle count. Bottled water is a safe drinking water source for those without access to or confidence in their in-home drinking water, though associated time and financial burdens are considerable. / Master of Science / An increasing number of Americans regularly choose bottled water over tap water as their preferred water source. Previous studies claim this is because of poor home tap water quality and/or distrust in public water sources. This study aims to understand tap and bottled drinking water quality and opinions in rural West Virginia and Kentucky, where unavailable and/or unsafe tap water has been reported.
Through partnerships with nonprofits in West Virginia and Kentucky, 24 homeowners were interviewed about their household water sources, uses, perceptions, motivations, and expenses. Water samples were also collected from homes, locally purchased bottled water, and other sources, including roadside springs. These samples were analyzed for regulated (bacteria, metals, nutrients) and emerging (per-and polyfluoroalkyl substances (PFAS), microplastics) contaminants and compared to federally enforceable standards for safety and aesthetics (if applicable).
The majority of participants described their in-home water quality as satisfactory or poor due to unpleasant taste, odor, and appearance. This finding aligned with in-home water quality results, which found coliform bacteria, E. coli, aluminum, iron, manganese, and sodium levels above United States Environmental Protection Agency (USEPA) standards and guidelines. Most homes (71 percent) reported bottled water as their primary drinking water source. While bottled water samples did not exceed any USEPA health-based standards or guidelines, homeowners reported spending an average of $68–80/month and driving up to 1 hour and 45 minutes to buy it. Emerging contaminants (PFAS and microplastics) were detected in all bottled and tap-water samples at relatively low levels. Therefore, although bottled water is a safe drinking water source for those without access to or confidence in their tap water, having to regularly purchase it represents a significant household burden.
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Evaluation of silver nanoparticles impregnated woven fabric microfiltration membranes for potable water treatmentAchisa, Cleophas Mecha 15 July 2014 (has links)
Submitted in fulfilment of the requirements of the Degree of Master of Technology: Chemical Engineering, Durban University of Technology, 2013. / Lack of access to clean and safe potable water, especially for people living in rural areas of developing economies, is a matter of great concern in different parts of the world. Measures taken to address the challenges arising from this problem include the improvement of existing water purification methods and development of new appropriate technologies such as point of use (POU) water treatment technologies.
One such appropriate POU technology is the Remote Rural Water Treatment System (RRWTS) developed at Durban University of Technology (DUT) in South Africa. The RRWTS is based on polyester woven fabric microfiltration (WFMF) membranes and other locally sourced materials. The filtration unit consists of flat sheet modules assembled into a pack and permeate outlets connected to a manifold and then to a tap. The system is gravity driven and therefore eliminates the use of pumps and electricity. This system has shown potential for use in water treatment as it produces permeate with turbidity below 1 NTU, has a high permeate flow rate, and is easy to use and maintain. However, the major challenge facing its use is that permeate does not meet the set microbiological standards for drinking water (zero E. coli in 100 mL treated water). The RRWTS can ideally remove 95 to 99 per cent of the influent E. coli. This necessitates the use of a separate disinfection step, often using chlorine for complete removal of microbial contaminants.
The objectives of this study were: to investigate the incorporation of silver nanoparticles (AgNPs) into the WFMF membrane; to evaluate the disinfection efficacy of the AgNPs impregnated filter (coated filter); and to determine the long term performance of the coated filter in terms of disinfection and silver elution (90 days).
The study was conducted in four stages. Firstly, AgNPs were incorporated on the membrane using in situ chemical reduction of silver nitrate using sodium borohydride. Secondly, the filters were characterized using scanning electron microscopy (SEM) to determine the morphology, and the Sessile drop method for contact angle measurement was employed to determine the membrane hydrophilicity. In addition, X-ray diffraction (XRD), Fourier Transform Infrared (FT-IR) spectroscopy and UV- Visible Spectroscopy
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were used to investigate the presence of AgNPs on the coated filter. Thereafter, the antibacterial efficacy of the filters was evaluated using a laboratory scale experimental rig and different microbial assays. Raw river water and deionized water spiked with E.coli (synthetic feed) were used as feed. Lastly, the effects of concentration of E.coli in the feed and silver elution on the disinfection performance of the coated filter over time were investigated. The performance criteria were based on permeate quality and they included: turbidity, concentration of E.coli, and silver concentration.
The characterization results depicted that AgNPs were successfully immobilized on the WFMF membranes by in situ chemical reduction. The incorporation of AgNPs was ascertained using UV-Vis Spectrophotometry, FT-IR and XRD. The Sessile drop test indicated that the membrane became more hydrophilic (77 per cent decrease in water contact angle) and the permeability increased significantly as a result of the coating (p <0.05). The coated filters demonstrated excellent filtration performance producing permeate with turbidity less than 1 NTU for feed turbidities between 40 and 700 NTU. The disinfection efficacy was found to be excellent, producing permeate with zero E.coli concentration for feed concentrations between 10,000 CFU/ 100 mL and 85,000 CFU/100 mL. The E.coli removal efficiency was 100 per cent for a period of 63 days of continuous filtration. The ICP Atomic Emission Spectrometer (ICP-AES) results showed that the leaching of silver from the coated filters over time (90 days) was always below 0.1 mg/L which is the widely accepted guideline for potable water.
From the literature surveyed, this is the first study which investigated the use of AgNPs in WFMF membranes for potable water disinfection. The coated filters treated water to the set international standards for potable water in terms of physical and microbiological quality.
However, the study did not comprise investigation into the effect of different silver loadings on the filter performance. The study also employed E.coli as the indicator organism for faecal contamination. The results obtained can be used as a model for future work using other microorganisms and different silver loadings in order to compare the performance.
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A NOVEL SOLAR THERMAL MEMBRANE DISTILLATION SYSTEM FOR DRINKING WATER PRODUCTION IN UNDEVELOPED AREASUnknown Date (has links)
In this research, a heat localizing solar thermal membrane distillation system has been developed for producing potable water from untreated surface water, wastewater, and seawater, using solely solar thermal energy. Unlike most other membrane technologies, this system requires no electrical power or equipment for its operation. The high production rate was achieved through the effective evaporation of water molecules within the pores of the membrane without dissipating much heat to the bulk feed water. It can remove suspending particles, microorganisms, inorganic salts, as well as organic contaminants from the feed water. The system can produce potable water for 32, 18, and 10 days on average under simulated sunlight when distilling seawater, canal water, and municipal wastewater, respectively, without cleaning the membrane. Low cost, high energy efficiency (i.e., 55%), and good water quality make the new system feasible for undeveloped areas where basic water treatment is lacking. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection
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Best practices in drinking water quality regulation elements of an Australian modelMoeller, Anthony. January 2001 (has links) (PDF)
Includes bibliographical references (p. 319-347) Mode of access: Internet via World Wide Web. Available at: http://business.unisa.edu.au/waterpolicylaw/documents/thesis.pdf Selected for archiving SSL
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Improving access to drinking water in the developing world through guided household water treatment and storage technology selectionNewton, Jessica 08 July 2011 (has links)
Beginning at least as early as 1977, the international community formally recognized that drinking water and sanitation were not a reality for large percentage of the world and that it was necessary to take action to change this. Over the following three decades more actions and agreements were made, each with a progressively acute awareness of the requirements to achieve this goal and the failures of previous attempts. Poor information sharing and underestimation of cost were identified as two of the greatest recurring impediments. The Millennium Declaration made in 2000 is the newest campaign to move towards this goal, among others, and provides a metric against which progress and success can be measured.
At this point, great success has been made overall towards the Millennium Development Goals. Millions of people have gained access to improved sources of drinking water and several regions have surpassed their goals. Unfortunately this progress is not homogenous and the definitions of success are misleading. Sub-Saharan Africa is lagging significantly behind due to water scarcity, large population growth, urban versus rural disparities, and slow growth of piped infrastructure. Limitations to the sector as a whole have been identified as logistics, funding limitations, inadequate cost recovery, and inadequate operations and maintenance. Additionally, the metric of access to an "improved" source does not equate to safe drinking water and is not attached to sanitation improvements or overall health improvements.
In further examining the financial aspects of achieving the goals, it is clear that there is a great deal of inconsistency. Many donors, whether public or private, international or local, are giving money to the development goals. But the money given is often not equivalent to the original commitment, not given to the countries with the greatest need, not given to the water and sanitation sector specifically, given in the form of loans which must be repaid, given to new large scale systems which are not always appropriate, or not sufficient to achieve the desired target. This makes it very difficult to achieve and sustain progress in the areas which have been difficult to reach thus far, including Sub-Saharan Africa.
The need for progress toward safe water is clear from the perspective of health. Water is needed for hygienic practices, as well as consumption, and it is counterproductive to use water that is not clean. One of the leading causes of both death and disability worldwide is diarrheal disease which can largely be attributed to unsafe water. Studies have shown that there is a positive correlation between drinking water interventions and improved health outcomes, especially with increased proximity of the source, and for this reason there is an even greater need to tie the definition of success in improved water to overall health outcomes. It is also important that public health practitioners, engineers, and professionals from other related sectors work together to improve knowledge sharing and ultimately efficiency in achieving the goal of safe water for all.
Point-of-use interventions are among the best approaches to delivering means of water treatment to unreached communities because they can be deployed much more quickly and easily than a traditional piped system, require less expertise, and reduce recontamination that may occur during transport and storage. Such technologies utilize a variety of mechanisms to address a range of contaminants and concerns. In order for any technology to be successful though, it must be accompanied by a method of safe storage as well as education, training, and continued external support.
This information is synthesized in a technology selection guide, which attempts provide assistance in technology selection by addressing the immediate issue of water quality for the sake of health benefits, while also considering the context of the installation, the user preferences, the level of expertise of the implementers, the cost, operations and maintenance requirements, and common areas of failure. Simultaneously it allows for technologies to be compared so that the most appropriate technology may be chosen. The guide is marketed towards a non-technical audience with the intention of promoting knowledge sharing and serving as a translation between the developers of the treatment technology and those who implement it in developing countries.
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Investigating Sources of Elevated Lead in Drinking WaterMcIlwain, Brad 22 May 2013 (has links)
Lead exposure poses as a risk factor for various adverse health effects including intellectual delays, reduced IQ, and behavioural problems in children, as well as cognitive decline in adults. Lead enters drinking water through corrosion of leaded materials such as lead pipes, solder, and brass devices.
Three rounds of residential and non-residential lead monitoring were conducted to evaluate the corrosion control implemented by Halifax Water, and to identify sites with elevated lead concentrations. Follow-up testing was conducted at several sites to determine the sources of lead, and the factors that contributed to high lead release. Finally, a bench scale experiment was conducted to determine the impacts of plumbing flux on metal release.
The lead action level for residential testing was exceeded only in the round that was conducted during the winter. Lead concentrations were also higher in the winter rounds than the fall round of non-residential sampling. The seasonal lead variation was likely caused by fluctuations in aluminum residuals in the water leaving the plant. Frequency of use, age, and outlet manufacturer were factors that were associated with elevated lead levels.
Follow-up studies were conducted at several fountains to determine the source of elevated lead levels. These fountains typically contained several leaded components and received infrequent use. Fountains with leaded components that received high, regular usage had often provided samples with low lead levels.
Drinking fountains that were banned and recalled in the US for potentially containing lead lined cooling tanks were found at eight locations throughout the study area. It was found that three of the eight likely contained the lined cooling tanks. High lead levels were present in samples collected from these fountains, even at sites with frequent usage. Low-use sites with the lead lined tank produced the highest lead levels in this study. Fountains suspected of containing lead lined tanks were removed and replaced, and the lead levels were significantly reduced at these sites.
The impact of plumbing flux on metal concentrations was relatively short in duration, lasting only a week for most metals, with the exception of tin. Lead levels were found to stabilize under all flux conditions following roughly 40 L of flushing. Flux type was the main factor contributing to the elevated metals. The traditional petroleum flux was much more resistant to flushing than the water soluble flux, as it caused elevated tin levels for several weeks and a tacky flux deposition in the copper pipe remained even three months after the start of the experiment. The high amount of chloride from the flux was aggressive towards the copper corrosion, but it is unclear if this would have led to copper pitting corrosion.
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Occurrence of Aeromonas hydrophila in surface water and distribution systems of East Central IndianaJarosh, John Joseph January 1999 (has links)
The bacterium Aeromonas hydrophila is a known fish and opportunistic human pathogen commonly occurring in surface waters supplying drinking water distribution systems. The major concern of government and drinking water providers is that A. hydrophila may invade and become established in the biofilm of a distribution system, thus potentially leading to outbreaks of disease. The purpose of this study was to survey source water, distribution system biofilm, and to establish a simulated distribution system to explore the possibility of A. hydrophila invading and becoming established under normal and disrupted treatment conditions. A. hydrophila (AH) medium and the API-20E system were used for identification, while Ampicillin-Dextrin Agar (ADA) was used for enumeration. Presumptive counts were high in source water approaching 103 CFU/ml during summer months. Biofiim from an actual distribution system showed the presence of A. hydrophila in 10 % of the samples. In the simulated distribution system A. hydrophila was never found in the bulk water or biofilm under normal treatment condition, showing disinfectant efficiency. Under disrupted treatment conditions A. hydrophila was not able to colonize a pre-established biofilm over a 14 week period. / Department of Biology
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Characterization of heterotrophic plate count (HPC) bacteria from biofilm and bulk water samples from the Potchefstroom drinking water distribution system / by S. WalterWalter, Sunette January 2009 (has links)
The presence of heterotrophic plate count (HPC) bacteria in drinking water distribution systems is usually not considered harmful to the general consumer. However, precautions must be taken regarding the immunocompromised. All water supply authorities in South Africa are lawfully required to provide consumers with high-quality drinking water that complies with South African-and international standards. This study mainly focused on the isolation, identification and characterization of HPC and other bacteria from biofilm-and bulk water samples from two sampling points located within the Potchefstroom drinking water distribution system. Based on five main objectives set out in this study, results indicated that the bulk water at the J.S. van der Merwe building was of ideal quality fit for lifetime consumption. Application of enrichment-and selective media allowed for the isolation of 12 different bacterial morphotypes. These were identified by way of biochemical-and molecular methods as Bacillus cereus, Bacillus subtilis, Brevundimonas spp., Clostridiaceae, Corynebacterium renale, Flavobacteriaceae, Kytococcus sedentarius, Leuconostoc lactic, Lysinibacillus sphaericus, Pseudomonas spp., Staphylococcus aureus and Staphylococcus capitis. The greatest diversity of bacteria was detected early autumn 2008, while the lowest diversity occurred during mid-winter 2007. Bacillus cereus, Kytococcus sedentarius and Staphylococcus capitis displayed potential pathogenic properties on blood agar. Kytococcus sedentarius could be classified as potentially the most pathogenic among the isolates. All isolates displayed multiple-resistant patterns towards tested antibiotics. Corynebacterium renale and Staphylococcus aureus were least resistant bacterial species and Lysinibacillus sphaericus the most resistant. All isolates were susceptible to ciprofloxacin (CIP) and streptomycin (S), but most were resistant to erythromycin (E). Transmission electron microscopy (TEM) allowed for detailed examination of Brevundimonas spp., Pseudomonas spp. and Staphylococcus spp. The capability of Brevundimonas spp. to produce slime and store nutrients within inclusion bodies, suggests the ability of this bacterium to form biofilm and persist in the drinking water for prolonged periods. Despite the inhibitory or toxic effect of copper against bacterial growth, scanning electron microscopy (SEM) revealed the presence of biofilms as well as diatoms on red-copper coupons. Biofilm activity was also observed on reverse-osmosis (RO) filters. Since corrosion was evident on red-copper coupons, it is recommended that prospective studies also look into the significance of microbial induced corrosion (MIC) within the Potchefstroom drinking water distribution system. Other prospects include determining minimum inhibitory concentrations of isolates against antibiotics and the application of culture independent methods such as SSCP and DGGE to investigate biofilm development. The use of diatoms as an index of the drinking water quality is also suggested. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2010.
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Characterization of heterotrophic plate count (HPC) bacteria from biofilm and bulk water samples from the Potchefstroom drinking water distribution system / by S. WalterWalter, Sunette January 2009 (has links)
The presence of heterotrophic plate count (HPC) bacteria in drinking water distribution systems is usually not considered harmful to the general consumer. However, precautions must be taken regarding the immunocompromised. All water supply authorities in South Africa are lawfully required to provide consumers with high-quality drinking water that complies with South African-and international standards. This study mainly focused on the isolation, identification and characterization of HPC and other bacteria from biofilm-and bulk water samples from two sampling points located within the Potchefstroom drinking water distribution system. Based on five main objectives set out in this study, results indicated that the bulk water at the J.S. van der Merwe building was of ideal quality fit for lifetime consumption. Application of enrichment-and selective media allowed for the isolation of 12 different bacterial morphotypes. These were identified by way of biochemical-and molecular methods as Bacillus cereus, Bacillus subtilis, Brevundimonas spp., Clostridiaceae, Corynebacterium renale, Flavobacteriaceae, Kytococcus sedentarius, Leuconostoc lactic, Lysinibacillus sphaericus, Pseudomonas spp., Staphylococcus aureus and Staphylococcus capitis. The greatest diversity of bacteria was detected early autumn 2008, while the lowest diversity occurred during mid-winter 2007. Bacillus cereus, Kytococcus sedentarius and Staphylococcus capitis displayed potential pathogenic properties on blood agar. Kytococcus sedentarius could be classified as potentially the most pathogenic among the isolates. All isolates displayed multiple-resistant patterns towards tested antibiotics. Corynebacterium renale and Staphylococcus aureus were least resistant bacterial species and Lysinibacillus sphaericus the most resistant. All isolates were susceptible to ciprofloxacin (CIP) and streptomycin (S), but most were resistant to erythromycin (E). Transmission electron microscopy (TEM) allowed for detailed examination of Brevundimonas spp., Pseudomonas spp. and Staphylococcus spp. The capability of Brevundimonas spp. to produce slime and store nutrients within inclusion bodies, suggests the ability of this bacterium to form biofilm and persist in the drinking water for prolonged periods. Despite the inhibitory or toxic effect of copper against bacterial growth, scanning electron microscopy (SEM) revealed the presence of biofilms as well as diatoms on red-copper coupons. Biofilm activity was also observed on reverse-osmosis (RO) filters. Since corrosion was evident on red-copper coupons, it is recommended that prospective studies also look into the significance of microbial induced corrosion (MIC) within the Potchefstroom drinking water distribution system. Other prospects include determining minimum inhibitory concentrations of isolates against antibiotics and the application of culture independent methods such as SSCP and DGGE to investigate biofilm development. The use of diatoms as an index of the drinking water quality is also suggested. / Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2010.
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Water storage in rural households intervention strategies to prevent waterborne diseases /Potgieter, Natasha. January 2007 (has links)
Thesis (PhD.(Medical Virology)--Faculty of Health Sciences)-University of Pretoria, 2007. / Includes bibliographical references.
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