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The effects of using a cation exchange water softener on blood pressureKang, Ki Sung 29 August 1990 (has links)
Water in 70 percent of the cities in the United
States is hard enough that softening is either required or
recommended. It is estimated that approximately 30
percent of all homes in the United States use water
softeners. Water softeners, the cation exchange types
suited for residential use, exchange sodium for the
calcium and magnesium in water. The increase in sodium
levels in the softened water caused by cation exchange
softening is a direct function of the hardness level of
the untreated water. For people who use groundwater,
which has a relatively high level of naturally occurring
sodium, magnesium and calcium, the additional sodium from
cation exchange water softeners may create health hazards
for the general population and could adversely affect those
who are sensitive to salt or on low sodium diets. To
prevent potential health hazards for the general
population, no consumption of softened water by cation
exchange water softeners should be recommended. If soft
water is needed for some practical reasons, a "Separate
Water Line System" should be recommended for homeowners. / Graduation date: 1991
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Piped water access, child health and the complementary role of education : panel data evidence from South AfricaWapenaar, Korstiaan Erich January 2017 (has links)
Thesis (M. Com. (Economics))--University of the Witwatersrand, Faculty of Commerce, Law and Management, School of Economic & Business Sciences, 2017 / This study establishes the causal impact of piped water access on child health in rural South Africa (2008 – 2015) through the use of a panel dataset and a quasi-experimental sample space. By employing an ordinal measure of child health as the dependent variable within ordinal probit, fixed and random effects, propensity-score matched difference-in-difference and system-GMM estimators, it is demonstrated that positive health benefits for children with access to piped water are observed if and only if the minimum level of educational attainment of the primary-caregiver is equal to or greater than 7 years. This finding of complementarity is demonstrated to be a function of an individual’s (in)capacity to evaluate water quality: people below this threshold suffer from a piped water bias, place insufficient weight on the observable characteristics of water when determining water quality and are subsequently less likely to treat piped water preceding consumption. The interactional effect estimates are statistically significant at the 5% level with the impact ranging from 1.617 to 2.008 levels. / GR2018
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Delivery of environmental health services to Ducats informal settlementSompani, Thozamile Matthews January 2003 (has links)
Thesis (MTech (Environmental Health))--Cape Technikon, 2003 / This study provides information on the provision of environmental health
services to informal housing settlements by local authorities.
A standard for Environmental Health Service delivery according to
Government policies and legislation has been provided. Actual
environmental health services delivered to Ducats informal settlement at
the time (1992), have been compared to the services that should have
been delivered by law.
Baseline data have been compiled by means of questionnaires, in order
to assist the different levels of government in addressing the housing and
environmental health needs of the Ducat community.
The nature of Environmental Health and the history of informal housing,
more specific that of the Ducat informal housing settlement, have been
determined.
Limited environmental health services were rendered to informal housing
settlements occupying land illegally during 1992. These environmental
health services were limited to basic sanitation, water supply and refuse
removal. Only pit latrines or bucket latrines were required as a means of
sanitation, tanks for water supply and skips for the disposal of waste.
Amatola Regional Services Council however rendered all the
environmental health services required.
Other environmental health aspects such as pest control, communicable
disease control, air pollution control, radiation, occupational health
issues, temperature extremes, lighting, ventilation, noise, social
environment, food and meat hygiene were not required.
This study has provided a set of Government policies and legislation,
which should be considered in rendering environmental health services
for housing in future.
Uncertainty of the past decade, about rendering of Environmental Health
services to people occupying land illegally, still persists. The Municipal
Structures Act, 117 of 1998 requires the rendering of Environmental
Health services by local authorities, but it does not state whether these
services should be rendered to people occupying land illegally as well.
Since this has been the biggest restriction in providing environmental
health services in the past, it is recommended that Government address
this uncertainty.
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Design and evaluation of a cost effective household drinking water treatment systemMahlangu, Themba Oranso 20 August 2012 (has links)
M.Sc. / The world is focusing on increasing the number of people who have access to safe drinking water due to the ascending numbers of drinking water related illnesses reported annually in rural areas where water is not treated before consumption. To meet this goal, household water treatment has to be introduced especially in places where homes are wide apart making centralised water treatment improbable. Most readily available household water treatment systems (HWTS) such as membrane filters may not be affordable in rural areas due to power requirements and degree of ability to use and maintain them. This study was therefore aimed at designing and constructing HWTS using readily available material such as sand, gravel, zeolites and clays. Five HWTS were designed, built, evaluated and compared based on their ability to remove chemical contaminants such as iron, arsenic and fluorides from drinking water. The types of filters that were used during this study are the biosand filter (BSF), a modified biosand filter with zeolites (BSFZ), a silver impregnated porous pot (SIPP) filter, a ceramic candle filter (CCF) and a bucket filter (BF). Effectiveness of the filters in reducing physical parameters such as turbidity and visual colour was also assessed. The water treatment devices had the following flow rates; 1.74 L/h – 19.20 L/h (BSFZ), 0.81 L/h – 6.84 L/h (BSF), 0.05 L/h – 2.49 L/h (SIPP) and 1.00 L/h – 4.00 L/h (CCF). The flow rates were high at the early stages of filter use and decreased with increase in the volume of water filtered through. The flow rates of the filters were affected by the turbidity of intake water which was between 1.74 NTU – 42.93 NTU and correlated to chlorophyll a concentrations. The household water treatment technologies reduced turbidity to levels less than 1 NTU (> 90% reduction) in the following order SIPP > BSFZ > BSF > CCF > BF. The filters achieved greater than 60% retention of calcium, magnesium, iron and arsenic. These contaminants with the exception of arsenic were reduced to acceptable levels of the South African National Standard of drinking water (SANS 241, 2004). Compared to the other filters, the BSFZ performed better in removing nitrates, phosphates and fluorides although the overall retention efficiency was low. Total organic carbon was removed greatly by the CCF (39%) and the least removal was by the BF. The overall performance of the filters in reducing contaminants from drinking water was in the order BSFZ > BSF > SIPP > CCF > BF. Filter washing vi resulted in an overall increase in the flow rates of the filters but negatively affected turbidity reduction. The filters still removed contaminants after total cumulative volumes of 1200 L (BSFZ, BSF, CCF and BF) and 300 L (SIPP) were filtered through the devices. The five evaluated filters have several advantages to the readily available technologies and the advantages include ease of construction, operation and maintenance. The filters are gravity driven and work independent of temperature. These HWTS incorporate safe storages fitted with spigots to eliminate recontamination of water when it is drawn for use. The filters can produce enough drinking and cooking water for a family of six members due to their high flow rates. The BSFZ, BSF, SIPP, CCF and BF may therefore be considered for treating contaminated water at household scale in places where water is taken directly from the source without treatment.
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Quality of drinking water sources in the Bloemfontein area of the Mangaung Metropolitan MunicipalityRatikane, Mosepeli January 2013 (has links)
Thesis (M. Tech. (Environmental Health)) -- Central University of technology, Free State, 2013 / Introduction: Drinking water of poor quality can cause a variety of diseases and may even result in death. The impact of poor drinking water is a course for concern even in South Africa. Therefore, the physical, chemical and microbiological drinking water quality was investigated in the peri-urban area of Bainsvlei and the Woodlands Hills Estate in Bloemfontein, Free State.
Materials and Methods: The water quality was assessed in 20 identified sampling sites for three series with ten weeks apart. These sites use treated municipal and untreated borehole water for drinking. The determinants analysed for were pH, electrical conductivity (EC), turbidity, temperature, Ca, Mg, Na, F, Cl, N, SO₄,N, Free chlorine, Al, As, CN, Fe, Mn, Pb, Hg, total coliforms and E. coli. The water samples were collected and analysed on site and in the laboratory. Both the physical and chemical determinants were measured using standard methods whereas the microbiological determinants were measured using the Defined Substrate Technology (DST) method. The measurements were first compared to the SANS 241 (2011) for compliance. The ANOVA tests were used to investigate if any seasonal variations existed in the water quality as well as to compare the levels of the determinants between borehole and municipal water. In the assessment of the overall drinking water quality of different water sampling sites the water quality index (WQI) was used.
Results and Discussions: Significant effects were believed to exist if the p-values of the ANOVA and Scheffe tests were at a significance level of 5% (p < 0.05). The study results revealed that of the four physical determinants that were measured turbidity exceeded the standard in many sampling sites in the three series. Of all the chemical determinants, nitrates exceeded the standard. In the same way coliforms exceeded the standard in a number of sampling sites while E. coli was found in a few sampling sites in the first series. ANOVA tests revealed that seasonal variations existed between pH, EC, temperature, cyanide and iron at a significant level of 5% (p < 0.05) while the Post-hoc Scheffe test further revealed the series in which the effect existed. Similarly, the ANOVA tests revealed that the levels of the determinants between municipal versus borehole varied in pH, EC, Ca, Mg, Na, F, Cl, N, and SO₄ at a significant level of 5% (p < 0.05). The WQI showed that in all the series when combining the good and excellent category season 2 had the highest percentage of 80%, followed by season 3 with 79% and season 1 with 70%. Only borehole sampling sites were found in the poor, very poor and unsuitable categories. Similarly all the highest WQI values were found in borehole sampling sites.
Conclusion: This study revealed that the water quality is of good quality in the Bainsvlei and Woodlands Hills Estate of the Mangaung metropolitan municipality in Bloemfontein, in the Free State, South Africa. The presence of E. coli, though found in a few sampling sites and the high levels of turbidity, nitrates and coliforms are of concern to public health.
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Is the shelf life of bottled water a cause for concern?Liee, Yvone Lieketseng 08 1900 (has links)
Thesis. (M. Tech (Biotechnology, Faculty of Applied and Computer Science))--Vaal University of Technology, 2011. / Bottled water like any drinking water used for human consumption should be safe and wholesome to ensure adequate public health protection. This is due to potential health effects of concern such as endocrine disruption, toxicity teratogenicity, mutagenicity and carcinogenicity. Despite the number of regulatory bodies, publications on bottled water and speculations on its public health significance, many questions remain to be answered. One of the questions is whether the shelf life of bottled water is a cause for concern. The aim of the study was to determine the shelf-life of various commercial bottled waters by monitoring the variation in microbiological, chemical and aesthetic qualities of bottled water. A total of five commercial bottled water brands (A, B, C, D, E) each containing bottles from the same batch consisting of spring water, mineral water and bottled tap water were purchased directly after being bottled from different distributors around Gauteng in South Africa. All samples were stored at room temperature with artificial lighting and controlled temperature for a year thus mimicking typical conditions in retail outlets, supermarkets and in homes. Analyses were conducted over a period of 12 months, at monthly intervals. Within days of being purchased, high Heterotrophic plate counts (HPC) bacteria exceeding drinking water alert level >5 000 cfu/ml was common in four bottled water brands. Growth succession occurred during the period of study as various algal species were growing and accumulating on all bottled water tested. Total coliforms (TC), faecal coliforms (FC) and E.coli were not detected in all the bottled water tested. Yeasts and moulds were also not detected in all the bottled water. There were insignificant variations during the period of study for turbidity, pH, TDS, conductivity, and colour. These did not indicate any potential impact on aesthetic quality of bottled water. Two bottled water brands had hardness measures as low as 11mg/ℓ as CaCO3 making the water too soft which has an effect on taste. Radioactive substances, trihalomethanes, heavy metals, pesticides and other chemical contaminants were not found at levels that can be detrimental to human health.
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Factors associated with the problematical of quality drinking water and public health in the municipality of Abomey-calavi in Benin / Facteurs associés à la problématique de la qualité de l'eau de boisson et la santé des populations dans la commune d'Abomey-calavi au BeninDegbey, Cyriaque 04 May 2011 (has links)
The objective of this research is double: <p>1) to study the factors associated with the problems of quality with drinking water on the physicochemical and biological level in the municipality of Abomey-Calavi in Benin ;<p>2)to study its relationships with public health. <p>The goal is to bring on one hand, the tools of improvement to the quality of water and public health in this commune. In addition, to contribute to the reduction of the rate of morbidity and mortality generated by the diseases related to drinking water contamination in this locality<p><p>Methods:<p>For the purpase of this study, we made a preliminary investigation in the municipality (households 55898 and almost all the households have the traditional wells). In the same way the information provided by the National Society of Water in Benin gave the indications on the level koverage of drinkable water conveyance of the commune. This study carried out within a general logical framework of the durable development based on an DPSIR analysis in the municipality of Abomey-Calavi of the Atlantic district in Benin made it possible to provide information on the main sources of contamination of the drinking water. We also carried out a random sampling of 110 wells and 110 households by taking account into the geographical distribution of the households in the commune. We selected 60 taps and 60 households by random sampling for those using water drink distributed by the national Society of Water in Benin. In each zone or district, three households consuming either well water or tap water were drawn randomly. A retrospective study on the number of cases of the hydrous diseases and other symptoms of hydrous diseases was carried out by consultation of medical registers of the commune from 2007 to 2009. Cases of diarrhoeas used as basic variable of health were compared with the other cases of hydrous diseases available in the files. <p><p>Results:<p>The results show that: the most al the well water taken in the households has temperatures beyond the recommendation of the World Health Organization (25 °C) and 98.2 % have a pH below the normal which is 6.5 to 8.5. We note a strong mercury and cadmium, complete iron, aluminum, nitrate nitrite pollution of the sampled wells (n=110) which is respectively 32.73%, 11.82%,10%, 43.64%, 6.36% and 14.55%. The results of the bacteriological analysis of water revealed that the totality of the wells is contaminated. The germs identified during the analysis of the well water are: Escherichia coli, fecal streptococcus species, bacterial salmonella ,Shigella ,Clostridium perfringens, staphylococcus species,<p> Klebsiella pneumoniae and Pseudomonas aeruginosa Most frequent among these germs are: Escherichia coli (100%), Klebsiella pneumoniae (97.27%), bacterial salmonella and Shigella (96,36%) with regard to the coliformes and enterobacteries. As for the cocci with Gram (+) they are staphylococcus species (97.27%) and the fecal streptococcus (88.18%). It is useful to stress that all the wells are strongly contaminated by Clostridium perfringens (95.45%).<p> The differences between the respective prevalence of parasitic coprology, uroculture, diarrhoeas, pains abdominal and saddles bloody for exposed (45.4%, 71.8%, 76.4% and 59.1%) :those who consume the water of wells not exposed (8.3%, 1.7%,13.3%, 16.7): those who consume tap water, are statistically significant (p<0.001). For diarrhoeas according to the characteristics of the people reached of hydrous diseases and other symptoms of hydrous diseases we have: <p>•\ / Doctorat en Sciences de la santé publique / info:eu-repo/semantics/nonPublished
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Issues regarding sustainability of rural water supply in ZambiaMusonda, Kennedy 02 1900 (has links)
The purpose of this dissertation was to identify factors that contribute to the sustainability of rural water supply facilities (WSFs). Twenty-four interviews were conducted: 16 from rural communities and 8 from water supply agencies. Key findings are that in order to achieve sustainability of WSFs, there is need to ensure that (1) there is an effective community organisation; (2) communities have the ability to operate and maintain WSFs; (3) communities are able to raise adequate user fees for purchasing spare parts; and (4) that there is a strong backup support at the district level to carry out major repairs. Major threats to the sustainability of WSFs include high poverty levels in communities, weak institutional framework and inability of communities to handle major breakdowns. / Social Work / M.A. (Social Work)
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Issues regarding sustainability of rural water supply in ZambiaMusonda, Kennedy 02 1900 (has links)
The purpose of this dissertation was to identify factors that contribute to the sustainability of rural water supply facilities (WSFs). Twenty-four interviews were conducted: 16 from rural communities and 8 from water supply agencies. Key findings are that in order to achieve sustainability of WSFs, there is need to ensure that (1) there is an effective community organisation; (2) communities have the ability to operate and maintain WSFs; (3) communities are able to raise adequate user fees for purchasing spare parts; and (4) that there is a strong backup support at the district level to carry out major repairs. Major threats to the sustainability of WSFs include high poverty levels in communities, weak institutional framework and inability of communities to handle major breakdowns. / Social Work / M.A. (Social Work)
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