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Consistently high levels of air pollutants such as sulphur dioxide, particle matter and nitric oxides have been observed in the Durban South (DS) industrial basin. The adverse health outcomes associated with ambient air pollution (AAP) exposure have underlying molecular mechanisms. Oxidative stress is a known outcome of AAP exposure and contributes to the exacerbation of adverse AAP related outcomes such as chronic obstructive pulmonary disorder (COPD) and asthma. Pregnant women are at increased risk of developing oxidative stress due to increased energy expenditure. Oxidative stress during pregnancy is linked to adverse birth outcomes such as intrauterine growth retardation and low birth weight. The mitochondria are the most abundant source of endogenous reactive oxygen species (ROS), making these organelles extremely susceptible to oxidative damage. Alterations in mitochondrial function by air pollutants can contribute to oxidative stress. Uncoupling protein2 (UCP2) is an anion carrier located on the inner mitochondrial membrane that regulates mitochondrial ROS production by reducing mitochondrial membrane potential (Δψm) through mild uncoupling. Genetic variation in genes that play a role in oxidative stress response is likely to influence susceptibility to oxidative stress related health outcomes. The aim of this study was to evaluate air pollution associated oxidative stress response in women from the DS industrial basin and determine the functional relevance of a common -866G/A promoter polymorphism in the UCP2 gene. Fifty pregnant women from DS and 50 from north Durban (DN; control) were recruited. The thiobarbituric acid assay (TBARS) and comet assay were performed to measure oxidative stress and DNA fragmentation. Mitochondrial function was evaluated by JC-1 Mitoscreen and ATP luminometry. Quantitative PCR (qPCR) was performed to measure mitochondrial DNA (mtDNA) damage. Antioxidant response was determined by qPCR to measure mRNA expression of superoxide dismutase 2 (SOD2), nuclear factor erythroid 2-related factor 2 (Nrf2) and UCP2 mRNA expression. Western blots were performed to quantify UCP2 and Nrf2 protein expression. The samples were genotyped using PCR - restriction fragment length polymorphism. Results from the TBARS assay showed women from DS displayed elevated levels of MDA, a marker for oxidative stress (0.07±0.06μM; p = 0.56). ATP (1.89 fold) and Δψm (45.3±17.2%; p = 0.8) were also elevated in women from DS, favouring free radical production. DNA fragmentation, as indicated by comet tail length was also higher in DS when compared to the control group (0.57±0.16μm; p = 0.037). Analysis of mtDNA viability showed a 0.49 fold change in mtDNA amplification in women from the industrialized DS. All antioxidant genes, i.e. Nrf2 (0.73 fold), UCP2 (1.58 fold), SOD2 (1.23 fold), were up regulated in women from DS. Analysis of protein expression showed a significant increase in UCP2 expression (0.08±0.03RBI; p = 0.049) and a significant decline in Nrf2 levels (1.68±0.84RBI; p = 0.03). The homozygous G genotype was significantly more frequent in DS (37.5%) than in DN (18.6%; p = 0.047; OR: 2.57; 95% CI: 1.353 to 4.885). This genotype exhibited higher MDA levels, comet tail length, Δψm, SOD2, Nrf2, and UCP2 expression than the AA/GA in genotype in women from DS (p > 0.05). This study found that pregnant women from a more industrialized area exhibit higher markers for oxidative stress and conditions that favour mitochondrial free radical production. / Thesis (M.Med.Sc.)-University of KwaZulu-Natal, Durban, 2012.

M.Phil. / The combustion of fuels in poorly designed cookstoves is a major anthropogenic source of atmospheric emissions with severe environmental and health implications. It is widely acknowledged that these challenges are best addressed with the development and dissemination of clean cookstoves. Widely used stove testing protocols (UCB Water Boiling Test and variants) are often single task-based and not representative of real-world uses or likely combinations of the manner in which fuels, stoves and pots may be used. The hypothesis of this study is that a stove testing procedure that provides for testing of stove/fuel/pot combinations, in a sequence of heterogeneous tests, provides a better representation of thermal performance and emissions than existing protocols based on prescribed fuels and fuel loads, and single tasks. The study aimed to develop and evaluate a set of testing protocols for determining thermal efficiency and emissions performance of domestic fuels and cooking devices to satisfy the rigorous performance specifications expected for claims under the Clean Development Mechanism (CDM) carbon trading market. The Heterogeneous stove Testing Protocol (HTP) was developed and documented as a complete set of standard operating procedures (SOPs), using a template derived from the Desert Research Institute (DRI), Reno, Nevada, and used for performance evaluation of fuel/stove combinations. The effect of pot size on the performance of two paraffin wick stoves and a pressurised paraffin stove was assessed and was found not to be a major factor, which affected thermal efficiency only at the high power setting. Power setting was found to influence the thermal efficiency and combustion performance of all stoves tested, indicating the need for assessment of the devices across the full range of power settings (where feasible). The HTP was also employed in characterising the combustion performance of coal stoves, using three different ignition methods, giving qualitative and quantitative results. Compared to the bottom-lit up-draft (BLUD) ignition method, the Basa njengo Magogo, also referred to as the top-lit up draft (TLUD) method, proved to be a better method of coal fires ignition, in terms of reduced CO:CO2 ratio and less smoke generation than in conventional braziers. The bottom-lit down-draft (BLDD) ignition method, incorporated in the SeTAR prototype coal stove, was found to be effective in fuel utilisation and improved combustion efficiency compared to the TLUD and BLUD methods, with CO:CO2 emission factors below 1% for 230 minutes. A number of parameters employed by the Water Boiling Test (WBT) were examined and compared with the HTP (e.g. turn-down ratio; simmer process; hot-start phase; use of standardised fuels and test pots). The HTP was found to provide more representative performance data over a wide range of use scenarios, the equivalent of providing performance curves rather than the minimum and maximum performance points provided by the WBT. The findings of this study have shown that the Heterogeneous stove Testing Protocol is consistent, robust, and transportable; making it a valuable tool for stove design improvements, and for the assessment of stoves under voluntary and compulsory carbon markets.

Thesis (M. Sc.(Geography)) -- University of Limpopo, 2019 / Global production of Platinum Group Metals (PGMs) is dominated by South Africa due to its large economic resources base in the Bushveld Igneous Complex (BIC). PGMs are used in a wide range of high technology applications worldwide including medicinal, industrial and commercial purposes, and its contribution to the Gross Domestic Product (GDP) and creating jobs for many. In an area where mining activities dominate, there are likely to be problems that need effective environmental management approaches, which can be facilitated through legislations. Marula Platinum Mine (MPM) is located in Limpopo province BIC which has the second largest number of mining productivity in South Africa. Environmental legislations have been put in place by the South African government in order to avoid or minimise the footprints caused by PGM mining. This study looked at environmental compliance with solid waste management practices by Marula Platinum Mine (MPM) as guided by Mineral and Petroleum and Resource Development Act (MPRDA) and National Environmental Management Act (NEMA) as well as the environmental impacts of MPM in the surrounding communities. Both primary (questionnaires, field observations and key informant interviews) and secondary (NEMA, MPRDA, journals, reports, pamphlets, internet and books) data was used to address the objectives of the study. Descriptive method and Statistical Package for Social Sciences (SPSS) version 25 were used for the analysis of data. The key research results revealed that MPM was compliant with 65% and 21% partially compliant with solid waste management practices. Only 14% of information on solid waste management practices could not be accessed because MPM is still operational. MPM had also had negative footprints on the surrounding villages such as dust generation and cracks on walls and floors on houses of community members, strikes and increase in the usage of substance abuse. Recommendations of the study are that MPM should address challenges that hinder environmental compliance so as to be 100% compliant with MPRDA and NEMA regulations. MPM should also provide other mitigation measures for blasting of explosives to reduce dust generation and problems of cracks on houses of surrounding village members.