Browsing by Author "Wozei, Eleanor"
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- ItemAmplifying local voices to reduce failure in the water, sanitation and hygiene sector(Royal Academy of Engineering, 2021) Barrington, D.J; Sindall, R.C; Chinyama, A; Morse, T; Sule, M.N; Beale, J; Kativhu, T; Krishnan, S; Luwe, K; Malolo, R.D; Mcharo, O; Odili, A; Ravndal, K.T; Rose, J; Shaylor, E; Wozei, EleanorWASH endeavours regularly fail. Sometimes this means that entire programmes do not achieve their stated aims, sometimes these failures are setbacks which can be rectified with sufficient reflection and action. This research aimed to develop an evidence base of how and why field-based WASH professionals in four sub-Saharan African countries believe failures occur, their experiences when sharing and discussing them within their organisations, and how they believe a culture conducive to publicly sharing and learning from failures could be nurtured.
- ItemApplication of a yeast-based assay protocol developed to monitor total oestrogenic activity induced by 17β-oestradiol in activated sludge supernatants from batch experiments(Lawrence Berkeley National Laboratory, 2006-04-11) Wozei, Eleanor; Hermanowicz, SWBatch experiments were carried out with activated sludge from laboratory reactors and a full-scale treatment plant spiked with 17β-oestradiol (E2). An oestrogen-sensitive yeast-based assay protocol, described in detail in a related publication, was used to measure reduction of E2-induced total oestrogenic activity from the sludge supernatant over a 15 d period after which the sludge was re-spiked to check for possible enhancement of reduction by pre-exposed sludge during an additional 15 d period. The reduction was generally improved by increasing sludge solids concentrations and by continuous mixing. For a 100 ngE2/ℓ spike there was >40% reduction of oestrogenic activity within 15 d, which improved to >70% by pre-exposing the sludge. The oestrogenic activity produced by a dose of 100 μgE2/ℓ was readily removed by most sludges within 15 d. How¬ever, re-spiking the activated sludge with the same E2 concentration caused some sludges to lose reduction capacity.
- ItemBiodegradation of Estrogenic Compounds and Its Enhancement in a Membrane Bioreactor – Research Category III, Water Quality(UC Berkeley Center for Water Resources Technical Completion, 2002-09) Hermanowicz, Slawomir W.; Wozei, EleanorIn the project, we investigated enhancement removal of estrogenic activities in activated sludge. These activities are caused by natural and synthetic substances that mimic the effect of the human hormone estrogen and they potentially can disrupt the endocrine systems of exposed species and the reproductive systems of aquatic fauna. Human and animal wastes are a source of natural and synthetic estrogens to the environment since only a fraction is removed in conventional wastewater treatment. A yeast-based assay developed previously was modified to detect the estrogenic activity in wastewater samples. Using the assay, it was possible to quantify estrogenic activity in range equivalent to between approximately 100ng/L to 100g/L of the female hormone 17-estradiol (E2), with sensitivity as low as 0.03ngE2/L. The assay is therefore sensitive to the concentrations of environmental estrogens typically found in wastewater and the new assay may be a useful tool for screening for estrogenic activity. Compared to existing chemical analytical methods, the new test is simpler and covers a wider range of compounds. This is important because by-products of some of the influent estrogens are also active estrogens. For example, E2 is metabolized to estrone and estriol, which are estrogenic. Monitoring the removal of only a few substances may underestimate the estrogenic properties of treatment plant effluents and solids disposed of into the environment. Further experiments were carried out to determine the removal of estrogenic activity from water. Results show that the presence of activated sludge enhances removal of total estrogenic activity by at least 40% within 10-15 days.
- ItemBiologically directed environmental monitoring, fate, and transport of estrogenic endocrine disrupting compounds in water: A review(Elsevier Publications, 2006) Campbell, Chris G.; Borglin, Sharon E.; Green, F. Bailey; Grayson, Allen; Wozei, Eleanor; Stringfellow, William T.Endocrine disrupting compounds (EDCs) are contaminants that may be hormonally active at low concentrations and are emerging as a major concern for water quality. Estrogenic EDCs (e-EDCs) are a subclass of EDCs that, when organisms are exposed to them, function as estrogens. Given that there are numerous e-EDCs that can negatively affect humans and wildlife, general screening techniques like biologically based assays (BBAs) may provide major advantages by estimating the total estrogenic effects of many e-EDCs in the environment. These techniques may potentially be adapted for field portable biologically directed sampling and analyses. This article summarizes available BBAs used to measure estrogenic e-EDCs in the environmental samples and also presents results relating to fate and transport of e-EDCs. Estrogenic EDCs appear to be almost ubiquitous in the environment, despite low solubility and high affinity of organic matter. Potential transport mechanisms may include: (1) transport of more soluble precursors, (2) colloid facilitated transport, (3) enhanced solubility through elevated pH, and (4) the formation of micelles by longer-chain ethoxylates. Due to their persistent and ubiquitous nature, source control strategies for e-EDCs may reduce influent concentration to wastewater treatment plants so that the post treatment effluent will decrease concentrations to estrogenically inactive levels. Alternatively if source reduction is not possible, then more testing is needed on tertiary treatment technologies and treatment efficiencies for e-EDCs. There is still a need for research on remediation and restoration approaches for habitats disturbed by elevated e-EDC concentrations.
- ItemCalibrating an optimal condition model for solar water disinfection in peri-urban household water treatment in Kampala, Uganda(IWA Publishing, 2013) Okurut, Kenan; Wozei, Eleanor; Kulabako, Robinah; Nabasirye, Lillian; Kinobe, JoelIn low income settlements where the quality of drinking water is highly contaminated due to poor hygienic practices at community and household levels, there is need for appropriate, simple, affordable and environmentally sustainable household water treatment technology. Solar water disinfection (SODIS) that utilizes both the thermal and ultra-violet effect of solar radiation to disinfect water can be used to treat small quantities of water at household level to improve its bacteriological quality for drinking purposes. This study investigated the efficacy of the SODIS treatment method in Uganda and determined the optimal condition for effective disinfection. Results of raw water samples from the study area showed deterioration in bacteriological quality of water moved from source to the household; from 3 to 36 cfu/100 mL for tap water and 75 to 126 cfu/100 mL for spring water, using thermotolerant coliforms (TTCs) as indicator microorganisms. SODIS experiments showed over 99.9% inactivation of TTCs in 6 h of exposure, with a threshold temperature of 39.5± 0.7 WC at about 12:00 noon, in the sun during a clear sunny day. A mathematical optimal condition model for effective disinfection has been calibrated to predict the decline of the number of viable microorganisms over time.
- ItemDetecting estrogenic activity in water samples with estrogen-sensitive yeast cells using spectrophotometry and fluorescence microscopy(2006-03) Wozei, Eleanor; Holman, H-Y.N.; Hermanowicz, S.W.; Borglin, S.Environmental estrogens are environmental contaminants that can mimic the biological activities of the female hormone estrogen in the endocrine system, i.e. they act as endocrine disrupters. Several substances are reported to have estrogen-like activity or estrogenic activity. These include steroid hormones, synthetic estrogens (xenoestrogens), environmental pollutants and phytoestrogens (plant estrogens). Using the chromogenic substrate ortho-nitrophenyl-β-D-galactopyranoside (ONPG) we show that an estrogen-sensitive yeast strain RMY/ER-ERE, with human estrogen receptor (hERα) gene and the lacZ gene which encodes the enzyme β-galactosidase, is able to detect estrogenic activity in water samples over a wide range of spiked concentrations of the hormonal estrogen 17β-estradiol (E2). Ortho-nitrophenol (ONP), the yellow product of this assay can be detected using spectrophotometry but requires cell lysis to release the enzyme and allow product formation. We improved this aspect in a fluorogenic assay by using fluorescein di-β-D galactopyranoside (FDG) as a substrate. The product was visualized using fluorescence microscopy without the need to kill, fix or lyse the cells. We show that in live yeast cells, the uptake of E2 and the subsequent production of β-galactosidase enzyme occur quite rapidly, with maximum enzyme-catalyzed fluorescent product formation evident after about 30 minutes of exposure to E2. The fluorogenic assay was applied to a selection of estrogenic compounds and the Synchrotron-based Fourier transform infrared (SR-FTIR) spectra of the cells obtained to better understand the yeast whole cell response to the compounds. The fluorogenic assay is most sensitive to E2, but the SR-FTIR spectra suggest that the cells respond to all the estrogenic compounds tested even when no fluorescent response was detected. These findings are promising and may shorten the duration of environmental water screening and monitoring regimes using yeast-based estrogen assays, and the development of biosensors for environmental estrogens designed to complement quantification methods.
- ItemDeveloping a yeast-based assay protocol to monitor total oestrogenic activity induced by 17β-oestradiol in activated sludge supernatants from batch experiments(Lawrence Berkeley National Laboratory, 2006-04-11) Wozei, Eleanor; Hermanowicz, SWA yeast-based assay protocol developed for detecting oestrogenic activity in activated sludge (AS) supernatant is described. The protocol used Saccharomyces cerevisiae construct RMY/ER-ERE with human oestrogen receptor (ERα) and lacZ reporter genes, and was developed by modifying existing assays for use with AS samples from batch experiments. The method was able to detect total oestrogenic activity (without prior extraction) in supernatants of AS spiked with 17β-oestra¬diol (E2) with a detection limit of 0.03 ngE2-equivalent/ℓ and an overall quantification limit of 100 ngE2-equivalent/ℓ. Mean E2-induced oestrogenic activity recoveries of >56% were obtained from the spiked samples.
- ItemExploring the Environmental Feasibility of Integrated Sanitation Systems for Uganda.(Journal of Sustainable Development of Energy, Water and Environment Systems, 2019) Agunyo, Miria F.; Born, Jens; Wozei, Eleanor; Moeller, BerndIn urban areas of Uganda, management of waste which consists of at least 70% organic content is accomplished by collection and disposal in landfills, resulting in emission of landfill gases among other impacts. Meanwhile, the limited number of wastewater and sludge treatment plants makes further management of sewage and faecal sludge generated from urban areas a major challenge. Thus, integrated sanitation systems which consider combined management of organic waste streams, i.e., bio waste, animal waste, sewage and faecal sludge, are proposed. The sanitation systems consist of a combination of anaerobic digestion and other technologies such as composting, incineration among others. Moreover, the systems also promote resource recovery in the form of biogas and organic fertilizer. The environmental feasibility of the integrated sanitation systems was investigated using life cycle assessment method. The results indicated that resource recovery contributed to the environmental feasibility of these sanitation systems. The more resources that were recovered from the sanitation systems, the lower the environmental impact.
- ItemHousehold drinking water characteristics in a peri-urban community: the case of Kifumbira Zone, Kampala, Uganda(35th WEDC International Conference, Loughborough, UK, 2011) Nabasirye, L.; Kulabako, R.; Atukunda, V.; Wozei, Eleanor; Kinobe, Joel; Okurut, Kennan; Arinaitwe, D.A study to determine the drinking water quality improvement practises at household level was undertaken in Kifumbira Zone, a Kampala peri-urban area, Uganda. The socio-economic conditions of 150 households were identified using questionnaires and in-depth interviews. Solar water disinfection (SODIS) was introduced to 10 households and water from their boiled drinking water and SODIS treated water was monitored for three months. The social survey indicated that boiling was the most common method applied to improve the drinking water quality – mainly using charcoal and electricity. 65% of the respondent households boiled their drinking water, while the rest consumed it unboiled due to the high cost of charcoal. The raw water sources exhibited microbiological contamination as evidenced by the presence of thermotolerant coliforms and high risk scores on the sanitary inspections conducted. There was a statistically significant difference (p<0.05; n=15) in the mean count of thermotolerant coliforms for boiled and SODIS treated water.
- ItemManagement structure as a factor of performance of Solid Waste Management projects in African municipalities: A case of Bushenyi-Ishaka Municipality, Western Uganda(Rwanda Journal of Engineering, Science, Technology and Environment, 2018) Okurut, Kenan; Nuwamanya, Moses; Isoke, Jennifer; Wozei, EleanorSolid waste production is growing exponentially, with stronger trends in developing countries. Uganda is facing rapid urbanization that offers not only new social and economic opportunities, but also more pronounced challenges, including waste management which is not coping with the population growth. Despite the financial support given towards solid waste management (SWM), there appears to be no apparent change. With a population growth of 4.8% per annum, the Bushenyi municipal waste problem is expected to worsen in future if its management is not taken seriously. This study was aimed at understanding how management structure has influenced the performance of a SWM project in Bushenyi-Ishaka Municipality. A mixed-method approach involving both quantitative and qualitative methods was employed in the study. The quantitative approach focused on counting and classifying features to explain what was observed, while the qualitative method, majorly Focus Group Discussions (FGDs), was used to provide a complete and detailed description of the existing situation in three Divisions of Bushenyi-Ishaka Municipality. The study showed that the project management structure does not provide adequate and equitable representation for each of the participating stakeholders at different levels of the project for the day-to-day activities and supervisory roles. It is evident that low resource input is partly contributing to the 27% performance of the Solid Waste Management project. SWM should be implemented with a dedicated management structure with adequate and well-skilled personnel for supervision and monitoring. In addition, the budget for municipal solid waste management should be increased to enable the municipal authority to fund the projects effectively.
- ItemRapid water sample screening for estrogenic activity using live yeast cells(2007) Wozei, Eleanor; Borglin, S. E.; Holman, H-Y.N.Endocrine disrupting compounds (EDCs) are substances that influence the endocrine system in living organisms. They include natural hormones, medicinal drugs, chemical compounds in industry, and pesticides in agriculture. The substances may be present in water and wastewater, soil and sediments, or airborne. Our research is focused on the estrogenic EDCs, i.e. substances which mimic the natural hormone estrogen produced by the body, and their occurrence and fate in the context of wastewater management. The primary contributors to estrogenic activity wastewater are 17_-estradiol, estrone, and 17_-ethinylestradiol. We are interested in readily detecting and quantifying this estrogenic activity as a first step in the daily management and reduction of estrogenic EDCs in wastewater before discharge into the environment with effluent and biosolids. We report progress on a fluorescence assay for the presence of estrogenic activity in water samples using a living estrogen-sensitive yeast cell strain, and on a study of responses of living yeast cells to estrogen and alkylphenol exposure using synchrotron radiation-based Fourier Transform infrared spectromicroscopy (SRFTIR). The fluorescent response of the yeast allows for rapid sample screening, and the SR-FTIR infrared spectrum is a measure of the overall in vivo yeast biochemical response to the sample.
- ItemReal-Time Molecular Monitoring of Chemical Environment in Obligate Anaerobes during Oxygen Adaptive Response(California Digital Library, University of California, 2009-08-26) Holman, Hoi-Ying N.; Wozei, Eleanor; Lin, Zhang; Comolli, Luis R.; Ball, David. A.; Borglin, Sharon; Fields, Matthew W.; Hazen, Terry C.; Downing, Kenneth H.Determining the transient chemical properties of the intracellular environment can elucidate the paths through which a biological system adapts to changes in its environment, for example, the mechanisms which enable some obligate anaerobic bacteria to survive a sudden exposure to oxygen. Here we used high-resolution Fourier Transform Infrared (FTIR) spectromicroscopy to continuously follow cellular chemistry within living obligate anaerobes by monitoring hydrogen bonding in their cellular water. We observed a sequence of well-orchestrated molecular events that correspond to changes in cellular processes in those cells that survive, but only accumulation of radicals in those that do not. We thereby can interpret the adaptive response in terms of transient intracellular chemistry and link it to oxygen stress and survival. This ability to monitor chemical changes at the molecular level can yield important insights into a wide range of adaptive responses.
- ItemRelationship between water quality and physical conditions of domestic storage tanks supplied by a water utility in a rapidly growing city(Water SA, 2021-01) Makoko, EW; Wozei, Eleanor; Birungi, LDomestic water storage tanks are commonly used in urban centres of developing countries such as Uganda to enable reliable access to water. However, little work has been done on the conditions of domestic water storage tanks since it is assumed that water received meets the required standards and guidelines for drinking water. In 2015, over 80% of the water quality complaints raised by water utility customers in Kampala were about water from storage tanks. In this study we assessed water quality in, and conditions of, domestic storage tanks, for customers supplied by a water utility from March – August 2017 in Kampala, Uganda. Longitudinal assessment of 372 storage tanks in 6 sampled wards involved a minimum of 6 samples collected from each site in both wet and dry months of 2017. A set of guiding questions was used to establish tank conditions, with a 'yes' or 'no' response and a range of 'low' to 'critical' risk ratings. The study showed that there were three main types of storage tanks: plastic (88%), concrete (7%), and metal (5%). Of these tanks, 84% were elevated, 41% were less than 5 years old, 69% were not cleaned annually, and 88% were covered. There was a statistically significant relationship (p < 0.05) between tank physical conditions and quality of stored water. Wards with unplanned and industrial settlements had the highest number of tanks with contaminated water. The study therefore revealed that the physical conditions and management of domestic water storage tanks have an effect on water quality. This is important information for a water utility as it means that it is not enough to supply safe water if the quality may deteriorate upon storage at the consumer premises. A routine inspection checklist and consumer guidelines for domestic storage tank management are proposed.
- ItemA report for a biology and chemistry primer for undergraduate students (abacus-1) – volume 1 general chemistry(2016-06) Tayebwa, Rodgers; Wozei, Eleanor; Gurley, Tom; Birikadde, Grace; Kimono, Diana; Nakayenga, Joyce