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Thesis (MTech (Physical Sciences))--Peninsula Technikon, Cape Town, 1999. / Wet deposition of toxic trace metals is the dominant mode of deposition in terrestrial ecosystems and contributes very significantly to their pollution burden. Wet deposited metals are dissolved in rainwater. They reach the vegatation in a form most favourable for uptake. Reliable analysis of toxic trace metals in rainwater is important in order to determine the impact they make on the environment. In this study, trace metals in rainwater and in dry deposition (as a control measure), have been analysed over a period of a year. These metals include cadmium, copper, cobalt, lead, nickel and zinc. The rainwater was filtered, acidified to pH2 and irradiated with UV-light. Dry deposition samples, were digested by heating in nitric acid before analysis. Differential-pulse anodic stripping voltammetry was used to determine cadmium, lead and zinc. Copper was determined by adsorptive cathodic stripping at pH7 after complexation with catechol. Cobalt and nickel were measured at pH9 by adsorptive cathodic stripping after formation of their dimethylglyoximes. Sampling was done on a daily basis from April 1996 to March 1997, on the campus of the Peninsula Technikon. The samples were collected over a 24-hour period. The total average concentration for the metals was 16.11 flg/dm3 for rainwater and 427flg/dm3 for dry deposition. Meteorological factors such as wind speed, humidity and temperature affect the distribution of pollutants and thus the trace metal levels. The levels of the metallic pollutants were thus evaluated against meteorological data. Differential-pulse stripping voltammetry is shown to be applicable for heavy metal analysis of rainwater.

The purpose of this study is to study the effect of water quality and quantity of raw water on advanced and conventional treatment processes. We are using data of water quality and quantity to investigate difference of quality of treated water in water treatment plant. Finally we compared items of ware quality ( turbidity, free residual chlorine, total hardness, conductivity, pH, NH3-N) whether passed the Taiwan¡¦s national standard of drinking water or not. We are hoping the treated drinking water will all fit the goal of high quality. Results show that high variation of turbidity was found from May to October in every year. The high turbidity was frequently occurred from 9.9% (2008) to 39.5% (2010). It indicated the worsen trend of water quality of raw water is increased yearly. In all monitoring items of water quality, turbidity, conductivity, NH3-N was greatly influenced in seasons from June to September. The rest items had no significant affect by season¡¦s variation. The removal efficiency in items of water quality of advanced and conventional WTP we found there were high value at hardness and TDS with 49.3% and 43.3% respectively. These items, water quality of treated water (such as turbidity, free residual chlorine, total hardness, conductivity, pH, NH3-N), were all pass the current drinking standard in Taiwan ( i.e., turbidity¡Õ2NTU¡BTDS¡Õ500mg/L¡B6.0¡ÕpH¡Õ8.5¡B0.2mg/L¡Õfree residual chlorine¡Õ1.0mg/L¡BNH3-N¡Õ0.1mg/L ).

M.Sc. (Environmental Management) / Surface water quality in the Blesbokspruit Ramsar wetland has been an area of concern since the 1990s, especially following the authorised and subsidised pumping of underground waters—high in salts—from Grootvlei Mine Shaft No. 3. The pumping was necessary to maintain their underground mining operations and to avert flooding of low-lying areas from decantation of derelict gold mines in the Blesbokspruit catchment. High levels of salt, coupled with a change in the flow of the system, contributed to the loss in the ecological character of the Blesbokspruit wetland in 1996 and, its subsequent listing on the Montreux Record during the same year. In Ramsar terms, the Blesbokspruit was under threat and on the brink of losing its international Ramsar status if management action was not taken to improve the surface water quality of this wetland. The Blesbokspruit has become, since 1996, a wetland in need of restoration to optimum hydrological conditions, i.e. water quality and quantity. A return to desirable water conditions in the Blesbokspruit wetland would enhance aquatic species diversity and abundance—especially the important waterfowl species that gave the Blesbokspruit wetland its international reputation. With the shutting down of the mine and the cessation of pumping operations at Grootvlei (Aurora) Mine in December 2010, the surface water in the Blesbokspruit wetland should have improved and enhanced the agricultural activities (irrigation and livestock watering) adjacent to this wetland, as well as contributed to healthier aquatic conditions much needed by local and migratory birds. An investigation of the surface water quality in the Blesbokspruit wetland was performed on historical water quality data for the period 2000 - 2011, obtained from Rand Water. The study revealed that there was a distinct seasonal and spatial pattern in the salts (i.e. sulphate, chloride, sodium, and magnesium), and related electrical conductivity and pH values for sites downstream of the underground water pumping point at Grootvlei Mine Shaft No. 3. Such observable seasonal and spatial patterns in the sites downstream of the underground mine-water discharge point could validate previous findings that had associated saline pollution with the pumping operations of Grootvlei Mine. Inter-annual trends showed a progressive decline in the concentrations of the salts and associated electrical conductivity values, with pH readings between neutral and slightly alkaline. Improvements in the salinity and acidity levels in the Blesbokspruit wetland could then be associated with the number of water management interventions adopted, particularly by Grootvlei Mine, from the mid-1990s until December 2010 (the year when mining and pumping operations ceased at Grootvlei Mine). Nevertheless, during the year 2011, the chemical properties of the Blesbokspruit revealed a step alteration—a substantial drop in concentrations of sulphate and magnesium salts—following cessation of underground pumping the preceding year, also confirming previous investigations linking saline water contamination to underground mine-water pumping operations at Grootvlei Mine.

A falta de acesso à água potável ainda é um problema de saúde pública no Brasil. O desenvolvimento de novos métodos analíticos de baixo custo para o reconhecimento de amostras contaminadas é uma necessidade, pois análises laboratoriais estão fora da realidade socioeconômica da população mais vulnerável. Visando contribuir para a resolução deste problema, esta tese apresenta esforços para o desenvolvimento de métodos de baixo custo para a análise de qualidade de águas ambientais. Foi estudada a associação de ferramentas quimiométricas com sensores voltamétricos para tentar discriminar amostras de águas contaminadas com espécies eletroativas. O modelo desenvolvido foi capaz de discriminar de forma satisfatória amostras contaminadas contendo chumbo(II), cobre(II), zinco(II) e nitrito. Os esforços para a redução do custo das análises também focaram no desenvolvimento de sensores com materiais de baixo custo. Um dos dispositivos voltamétricos propostos foi capaz de quantificar metais tóxicos e pesticidas, utilizando papel, grafite e cera. Foi desenvolvido também um sistema de agitação por som que resultou em um aumento significativo da sensibilidade dos dispositivos voltamétricos portáteis permitindo a quantificação de chumbo(II) até 48 nmol L-1, cádmio(II) até 370 nmol L-1 e zinco(II) até 340 nmol L-1. Outro sensor voltamétrico foi confeccionado utilizando apenas papelão como matéria prima, para o qual um laser de CO2 foi utilizado pela primeira vez com o intuito de pirolisar a superfície do papelão gerando estruturas de carbono condutoras. Sensores colorimétricos em papel foram testados com sucesso para a quantificação de fluoreto até 500 µmol L-1 em amostras de água mineral utilizando fotografias retiradas por um telefone celular para a construção de modelos12 de calibração. Com outro sistema colorimétrico em papel foi possível medir o pH de amostras utilizando um método de calibração multivariada. Como mostrado neste trabalho, o desenvolvimento e a integração dos dispositivos analíticos em papel é uma alternativa abrangente, confiável e de baixo custo para a análise da qualidade de águas ambientais. / The lack of access to safe water remains as a public health problem in Brazil. The development of new analytical methods for low cost contaminated samples recognition is necessary since the complete laboratorial procedures are away from the reality of the most socioeconomic vulnerable population. In order to contribute to solve this problem, this thesis shows our efforts to develop new low-cost analytical methods to evaluate environmental waters quality. The combination of chemometric tools with voltammetric sensors was studied to discriminate contaminated water samples with electroactive species. The proposed model was able to discriminate potable and contaminated samples containing lead(II), copper(II), zinc(II) and nitrite species. Efforts to reduce the analysis cost have also focused on the development of sensors using low-cost materials. A proposed voltammetric device fabricated with paper, graphite and wax was able to quantify heavy metals and pesticides. The use of a sound agitation system for the portable voltammetric devices resulted in a significant increase in the sensitivity allowing the quantification of lead(II) above 48 nmol L-1, cadmium(II) above 370 nmol L-1 e and zinc(II) above 340 nmol L-1 . Another voltammetric sensor was made for the first time using only cardboard as material and a CO2 laser to pyrolyze the cardboard surface generating conductive carbon structures. Paper colorimetric sensors were successfully tested for fluoride quantification in spring water samples based on photographs taken by a smartphone with a LOQ of 500 µmol L-1. Another paper colorimetric system was capable to measure the pH of samples using a multivariate calibration method. As shown in this thesis, the development and integration of analytical paper-based devices is a reliable and low-cost alternative for water quality analysis

A falta de acesso à água potável ainda é um problema de saúde pública no Brasil. O desenvolvimento de novos métodos analíticos de baixo custo para o reconhecimento de amostras contaminadas é uma necessidade, pois análises laboratoriais estão fora da realidade socioeconômica da população mais vulnerável. Visando contribuir para a resolução deste problema, esta tese apresenta esforços para o desenvolvimento de métodos de baixo custo para a análise de qualidade de águas ambientais. Foi estudada a associação de ferramentas quimiométricas com sensores voltamétricos para tentar discriminar amostras de águas contaminadas com espécies eletroativas. O modelo desenvolvido foi capaz de discriminar de forma satisfatória amostras contaminadas contendo chumbo(II), cobre(II), zinco(II) e nitrito. Os esforços para a redução do custo das análises também focaram no desenvolvimento de sensores com materiais de baixo custo. Um dos dispositivos voltamétricos propostos foi capaz de quantificar metais tóxicos e pesticidas, utilizando papel, grafite e cera. Foi desenvolvido também um sistema de agitação por som que resultou em um aumento significativo da sensibilidade dos dispositivos voltamétricos portáteis permitindo a quantificação de chumbo(II) até 48 nmol L-1, cádmio(II) até 370 nmol L-1 e zinco(II) até 340 nmol L-1. Outro sensor voltamétrico foi confeccionado utilizando apenas papelão como matéria prima, para o qual um laser de CO2 foi utilizado pela primeira vez com o intuito de pirolisar a superfície do papelão gerando estruturas de carbono condutoras. Sensores colorimétricos em papel foram testados com sucesso para a quantificação de fluoreto até 500 µmol L-1 em amostras de água mineral utilizando fotografias retiradas por um telefone celular para a construção de modelos12 de calibração. Com outro sistema colorimétrico em papel foi possível medir o pH de amostras utilizando um método de calibração multivariada. Como mostrado neste trabalho, o desenvolvimento e a integração dos dispositivos analíticos em papel é uma alternativa abrangente, confiável e de baixo custo para a análise da qualidade de águas ambientais. / The lack of access to safe water remains as a public health problem in Brazil. The development of new analytical methods for low cost contaminated samples recognition is necessary since the complete laboratorial procedures are away from the reality of the most socioeconomic vulnerable population. In order to contribute to solve this problem, this thesis shows our efforts to develop new low-cost analytical methods to evaluate environmental waters quality. The combination of chemometric tools with voltammetric sensors was studied to discriminate contaminated water samples with electroactive species. The proposed model was able to discriminate potable and contaminated samples containing lead(II), copper(II), zinc(II) and nitrite species. Efforts to reduce the analysis cost have also focused on the development of sensors using low-cost materials. A proposed voltammetric device fabricated with paper, graphite and wax was able to quantify heavy metals and pesticides. The use of a sound agitation system for the portable voltammetric devices resulted in a significant increase in the sensitivity allowing the quantification of lead(II) above 48 nmol L-1, cadmium(II) above 370 nmol L-1 e and zinc(II) above 340 nmol L-1 . Another voltammetric sensor was made for the first time using only cardboard as material and a CO2 laser to pyrolyze the cardboard surface generating conductive carbon structures. Paper colorimetric sensors were successfully tested for fluoride quantification in spring water samples based on photographs taken by a smartphone with a LOQ of 500 µmol L-1. Another paper colorimetric system was capable to measure the pH of samples using a multivariate calibration method. As shown in this thesis, the development and integration of analytical paper-based devices is a reliable and low-cost alternative for water quality analysis

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Biomedical Technology in the Faculty of Health and Wellness Sciences at the Cape Peninsula University of Technology, 2012 / In many developed countries worldwide the provision of safe, clean water is an expected commodity. In South Africa however, as in most developing countries, the access and supply of water safe for human consumption is challenged or complicated by pollution and more recently water availability. Point-source pollutants in surface- and groundwater are normally the most concentrated closest to the pollutant source (such as the end of a pipe or an underground injection system). Examples of point-source pollution are commercial and industrial businesses, that often discharge waste such as solvents and heavy metals from their operations. In contrast, non-point-source pollution occurs due to runoff moving across or through the ground and absorbing and accumulating pollutants which eventually end up in streams, rivers and dams. The lack of waste removal and adequate sanitation facilities results in the disposal of faecal matter and sewage into storm water drains which flow directly into the river systems contributing to the incidence of diseases such as gastroenteritis, diarrhoea and chronic lung ailments, caused by waterborne pathogenic bacteria, viruses and fungi. Routine water quality analysis however, does not include monitoring for viral contaminants, as this process is hampered by the lack of simple, reliable, time- and cost-effective testing methods to concentrate and detect viral pathogens. The primary aim of this study was thus to establish and optimise routine monitoring techniques for the detection of rota-, adeno- and enteroviruses in the Berg- and Plankenburg Rivers, Western Cape. Initially, various concentration and extraction methods were compared for the optimum recovery of viruses from spiked water samples. One hundred milliliter water samples were spiked with one milliliter rotavirus and two milliliters adenovirus control virions (Coris Bioconcept, Gembloux, Belgium). Optimisation testing of enterovirus was however, not completed due to the unavailability of a positive control. Four viral concentration techniques, namely the Silicon dioxide (SiO2) method, positively charged, negatively charged and the mixed-ester filters, were compared. Various nucleic acid extraction methods were also employed to establish which method would provide optimum yields for both DNA and RNA nucleic acids. The extraction techniques included the TRIzol method (Invitrogen, California, USA) for RNA extraction, the Roche High Pure PCR Template Preparation kit (Roche, Mannheim, Germany) for DNA extraction, and the QIAamp Ultrasens Virus kit (Qiagen GmbH, Hilden, Germany) for simultaneous RNA and DNA extraction. The use of virus specific primers within the PCR technique was also optimised. In addition, gene specific primers and oligo(dT)15 primers were tested and compared to establish which primers would yield the best results since gene specific primers are said to be more sensitive than oligo(dT)15 primers (van Pelt-Verkuil et al., 2008) when synthesising cDNA (rotavirus). The SiO2 concentration method yielded variable results when it was used with the various nucleic acid extraction techniques in this study, since positive PCR results were obtained when used in combination III with some techniques, while negative results were obtained with others. Similarly, variable results were also obtained when negatively charged filters were used to concentrate virus particles, and when this method was used in conjunction with various virus nucleic acid extraction techniques to identify different viruses by RT-PCR and PCR. Results for the non-charged mixed-ester filter were comparable to the positively charged filters when used in conjunction with the various nucleic acid extraction techniques in this study. Both these techniques yielded the highest viral particle concentration from the spiked water samples. Pilot study results indicated the presence of rotavirus and adenovirus detected by RT-PCR and PCR respectively, when filtering through the positively charged filter. The positively charged filter/QIAamp UltraSens virus kit combination was found to be the optimum combination when analysing the spiked water results and was then employed for the concentration of virus particles in the river water samples collected from the Plankenburg- and Berg River systems throughout the study period. The expected PCR product of 346 bp for rotavirus was absent in all 72 river water samples analysed for both river systems. In contrast to the PCR results obtained for rotavirus, the expected product of 261 bp for adenovirus was detected in 22 (30.5%) samples collected throughout the study period. Fifteen of the 22 adenovirus positive samples were found in the Plankenburg River (distributed over all sites), while seven of the 22 adenovirus positive samples were found in the Berg River (all sites). A nested PCR was used to detect enterovirus in the river water samples collected from both river systems throughout the study period. In the first round of the enterovirus PCR 15 river water samples (at various sites for both river systems) yielded a faint 513 bp product. Further amplification by nested PCR then yielded 13 (18.1%) positive nested PCR products of 297 bp. The incidence of adenovirus and enterovirus in river waters reported in the current study and the Van Heerden et al. (2003) investigation motivates for similar studies to be conducted in drinking water, dam water used for recreational purposes as well as rainwater, which is gaining popularity as a sustainable water source.

Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2012. / In many developed countries worldwide the provision of safe, clean water is an expected commodity. In South Africa however, as in most developing countries, the access and supply of water safe for human consumption is challenged or complicated by pollution and more recently water availability. Point-source pollutants in surface- and groundwater are normally the most concentrated closest to the pollutant source (such as the end of a pipe or an underground injection system). Examples of point-source pollution are commercial and industrial businesses, that often discharge waste such as solvents and heavy metals from their operations. In contrast, non-point-source pollution occurs due to runoff moving across or through the ground and absorbing and accumulating pollutants which eventually end up in streams, rivers and dams. The lack of waste removal and adequate sanitation facilities results in the disposal of faecal matter and sewage into storm water drains which flow directly into the river systems contributing to the incidence of diseases such as gastroenteritis, diarrhoea and chronic lung ailments, caused by waterborne pathogenic bacteria, viruses and fungi.

No controle da qualidade da água, parâmetros microbiológicos são avaliados e devem estar de acordo com os limites estipulados em portarias e resoluções. Todas as metodologias de monitoramento microbiano demandam o cultivo dos organismos-alvo. Em muitos casos, as cepas isoladas devem ser analisadas por teses fenotípicos para determinação da espécie. Por meio de inóculos de E. coli, demonstrou-se que a variação na técnica de plaqueamento se deve especialmente à falta de consistência entre as diluições. Além disso, para a análise de réplicas, comarando-se as médias de dois métodos de diluição, foi demonstrado que ser utilizado apenas uma série de diluição derivada de um único inóculo. Utilizando-se culturas puras de E. coli, E. faecalis e P. aeruginosa, a recuperação foi similar entre os meios seletivos respectivos (m-Endo, m-EI, m-PA-C) e meio não seletivo (Tripticase Soy Agar). A utilização da técnica de membrana filtrante resultou em contagens significativamente maiores para E.coli e E. faecalis em comparação ao método de spread plate. A microbiota natural presente na água potável (torneira) não influenciou significativamente as contagens de E. coli, E. faecalis e P. aeruginosa em meios seletivos. Entretanto, na água mineral engarrafada inoculada artificialmente com P. aeruginosa, a contagem foi significativamente maior na réplica estéril. Na análise de água marinha, e na réplica não estéril inoculada com E. faecalis, a contagem foi signifivativamente menor e as células de P. aeruginosa produziram colônias atípicas. Analisando-se amostras do meio ambiente (biofilmes de estação de tratamento de água, lodo de esgoto e água de córrego contaminado), 45 colônias típicas isoladas em meios de cultura seletivos foram identificadas por meio do sequenciamento do gene 16S rRNA, testes bioquímicos e MALDI-TOF. Os resultados de sequenciamento do gene 16SrRNA tiveram baixa correlação com a identificação dos organismos por testes bioquímicos (46,6% em nível de gênero e 20% em nível de espécie) e MALDI-TOF (60% em nível de gênero e 48,8% em nível de espécie). Para as cepas identificadas como E. coli e Enterococcus spp., a correlação entre o sequenciamento e MALDI-TOF foi de 75% e 62%, respectivamente. Uma vez que a quantificação de micro-organismo por membrana filtrante depende do micro-organismo em análise e do tipo de água, é necessário que os laboratórios realizem testes de padronização antes de implementar essa metodologia. Os resultados demonstram que os métodos convencionais utilizados não são adequados e suficientes para a análise da qualidade da água e, portanto, novas metodologias devem ser empregadas. Idealmente devem ser utilizadas técnicas baseadas em características fenotípicas, genômica e proteômica cujos resultados são complementares e fornecem uma identificação mais acurada. / All over the world regulatory agencies specify microbiological water quality parameters to guarantee water safety. Conventional microbiological water quality analysis is based on the cultivation of the target organisms. In many analysis protocols, phenotypic assays of isolated strains are mandated for species determination. Reference samples are required for quality assessment and quality control of analytical protocols. Using E. coli as a model organism, it was demonstrated here that the variability of plate counts of reference cultures is caused mainly by the spread of counts in individual serial dilutions. Besides, comparing the means obtained by two dilution approaches, it was demonstrated that in the analysis of replicates it is possible to use only a set of dilutions derived for a unique inoculum. Recovery of pure cultures of E. coli, E. faecalis and P. aeruginosa was similar on selective culture media (m-Endo, m-EI, m-PA-C) and with the non-selective medium (Tripticase Soy Agar). The membrane filter technique yielded significantly higher counts for E.coli and E. faecalis in comparison to spread plate method. The autochthonous microbiota of potable water (tap water) did not influence the counts of E. coli, E. faecalis and P. aeruginosa on selective culture media. However, the sterile replica of mineral water spiked with P. aeruginosa showed higher counts for these bacteria. For marine water analysis, the non-sterile replica spiked with E. faecalis yielded low counts and P. aeruginosa produced an atypical colony. Both, sample-induced variation in target strain recovery and colony appearance on culture plates indicates the requirement for method evaluation tests on particular sample matrices before implementing routine microbiological analysis by culture-based methods in the laboratory. 45 typical colonies obtained from environmental samples in selective culture media (biofilms from activated sludge, drinking water treatment plants and water from creek contaminated with raw sewage) were analyzed by 16S rRNA gene sequencing, biochemical phenotypic assays and MALDI-TOF. Sequencing showed low correlation with phenotypic assays (46,6% at the genus level and 20% at the species level) and MALDI-TOF (60% at the genus level and 48,8% at the species level). On the other hand, the strains identified as E. coli an Enterococcus spp. by 16S rDNA gene sequencing demonstrated a high correlation with MALDI-TOF (75% and 62%, respectively). Since the results showed that conventional methods aren´t suitable and sufficient to assess water quality, new technologies should be employed. Ideally, techniques should be based on phenotypic, genomic and proteomic features since the results are complementary and provide a more accurate identification.