Bibliography: pages 103-119. / The aims of this study were (a) to examine the profile of hospital admissions for selected respiratory illnesses for two major hospitals in Cape Town, and (b) to analyse the association of such admissions with air pollution indicators and meteorological variables. The first part of the study investigated the admission patterns of coloured and African children under twelve years of age who were diagnosed as suffering from asthma or acute respiratory infections at two major teaching hospitals in Cape Town. Computerized hospital admission records covering the years 1988-1990 from the overnight holding wards of the Red Cross War Memorial Children's Hospital and Tygerberg Hospital were used to determine patterns with respect to diagnosis, gender, race, age and date of admission. During the three year study period, respiratory admissions at both hospitals accounted for 15 078 (47.3%) out of a total of 31 887 admissions. Acute respiratory infections accounted for 63.6% and asthma 37.4 % of these respiratory admissions. Two factors of interest were noted: (1) Considerably more males than females were admitted with both asthma and acute respiratory infections. (2) Asthma admissions to Red Cross Hospital among African children were proportionally much less than those of coloured children when compared to the proportions of admissions for acute respiratory infections. After removal of the seasonal effect, a multiple linear regression model was fitted to the data to determine the individual associations between admissions and ambient environmental variables. Significant associations were found between: (1) acute respiratory infections and oxides of nitrogen, soiling index, and temperature; (2) asthma and oxides of nitrogen (3) total admissions and soiling index, average temperature and minimum temperature (negative). The study concluded that despite generally low levels of air pollution in Cape Town, childhood respiratory admissions to Red Cross War Memorial Children's Hospital and Tygerberg Hospital were statistically significantly associated with some ambient air pollutants as well as temperature. However, given the nature of both the exposure and admissions databases, these results should be treated with caution. More representative site selections for air pollution monitors, as well as searching and controlling for possible confounding factors (i.e. indoor air pollution, parental smoking, overcrowding), would allow a better understanding of the current air pollution problem and the possible effects on the respiratory health of children in metropolitan Cape Town.

M.A. (Psychology) / The study of behavioural toxicology was started in 1972 with the Port Pirie Cohort study and therefor a relative young field. Little information is available about the effect of cigarette smoke, containing the toxic substance carbon monoxide, on the neurocognitive functioning of children. The purpose of this study was to determine whether carbon monoxide has an effect on the neurocognitive functioning of children, more specifically as it relates to school performance. A group of school children was selected in the Vaal Triangle area who were sUbjected to a large quantity of cigarette smoke during the day and a group of children was selected who had no contact with any cigarette smoke during the day. The results of these groups were compared. From the results obtained it appears that cigarette smoke, would have a negative neurocognitive functioning of the children.

Ph.D. / The toxicant dichlorodiphenyl-trichloroethane, commonly known as DDT, is a broad spectrum insecticide and is currently banned in most countries due to its toxic effects. However, in some countries restricted use of DDT has been authorized as an effective vector control within malarial control programmes. South Africa is one such country, where spraying of DDT occurs in three provinces including the Limpopo Province, KwaZulu Natal and Mpumalanga. Specifically in the Limpopo Province, spraying of DDT has been ongoing for almost 56 years within the eastern malaria belt of the province. Despite this long term spraying there is still a scarcity of data regarding DDT and its effects on indigenous aquatic organisms in South Africa. Any research regarding DDT will therefore be of the utmost value. It was in this context that the present study was initiated, which primarily aimed to assess the extent of contamination within DDT sprayed areas in South Africa and the associated effects on indigenous species, whilst identifying techniques that could be used in future monitoring of these areas. This assessment was done in the Luvuvhu River catchment at three reference sites and four exposure sites situated within the areas where indoor residual spraying of DDT is done annually. At these sites the extent of DDT contamination within the water, sediment and biota (using the bioindicator pecies C. gariepinus from only the lentic sites) in the Luvuvhu river was evaluated. The results showed that DDT concentrations were well above recommended levels in all three of the measured phases, with the highest concentrations predominantly observed at the Xikundu weir. This site was particularly impacted by DDT due to a combination of its close proximity to the DDT sprayed areas, concentration accumulation from upstream sources and environmental conditions that accentuated contamination. These elevated levels of DDT did, however, not induce significant quantifiable effects in the bioindicator C. gariepinus or in the fish and macro-invertebrate community structures. Specifically, the effects in the catfish, C. gariepinus, were assessed using a range of biomarkers specific to the endocrine disrupting effects of DDT, including indirect measures of vitellogenin (calcium, zinc, magnesium and alkali-labile phosphate (ALP) that are all present on the VTG molecule in high abundances), gonad-somatic index (GSI), condition factor (CF), analysis of covariance (ANCOVA) manipulated gonads, protein carbonyls (PC) and intersex. Although none of these biomarkers could be significantly correlated with the DDT contaminations, DDT was shown to induce a slight sub-organismal effect by slightly inducing the synthesis of ALP and Ca as well as reducing the gonad mass (shown by GSI and adjusted gonad mass biomarkers) and body condition. In contrast, the fish and macroinvertebrate communities showed no conclusive relationship with DDT contamination, using a variety of methodologies, including informal assessments, univariate diversity indices, multivariate statistics, abundance models, fish response assessment index (FRAI) as well as average score per taxon (ASPT) and Ephemeroptera, Plecoptera and Trichoptera (EPT) richness. In conclusion, it was shown that DDT concentrations within the Luvuvhu River only induced effects at the lower levels of complexity, which highlights the importance of the utilisation of biomarkers to measure more subtle long-term effects as compared to the usage of community level effects.

Powdered laundry detergents are consumed in high volumes worldwide. Post use, they are directed toward water resources via wastewater treatment works or, as is the situation in many rural areas of South Africa, they enter the environment directly as a result of laundry washing activity undertaken alongside surface waters. Within wastewater treatment works, the main ingredient in powdered laundry detergents, the narcotic toxin linear alkylbenzene sulfonate (LAS), is mostly removed, rendering the waste stream a negligible risk to the aquatic biota of receiving waters. In contrast, the biological and ecological impacts of direct LAS input to the aquatic environment, as a consequence of near-stream laundry washing, are yet to be fully realised. Consequently, this thesis posed two research questions: 1) 'What are the LAS concentrations in a small rural South African river'? and 2) 'Is the in-stream biological community negatively affected at these concentrations?' The chosen study area, the community of Balfour in the Eastern Cape Province, is like many rural areas of South Africa where inadequate provision of piped water to homesteads necessitates laundry washing alongside the nearby Balfour River. The first research question was addressed in two ways: by predicting LAS concentrations in Balfour River water by assessing detergent consumption and laundry washing behaviour of residents living alongside the river; and measuring actual in- stream LAS concentrations on different days of the week and during different seasons. Results indicated that LAS concentrations were highly variable temporally and spatially. High peak concentrations of LAS occurred infrequently and were limited to the immediate vicinity of near-stream laundry washing activity with the highest measured concentration being 342 μg.L ⁻¹ and the average 21 μg.L ⁻¹ over the sampling period. The second research question was addressed by integrating the chemical evidence, determined from the first research question, with the biological evidence of stress responses measured in macroinvertebrates collected downstream of near-stream laundry washing activity on the Balfour River. Predicted and measured LAS exposure concentrations from the Balfour River were compared to a water quality guideline for LAS (304 μg.L ⁻¹), specifically derived in this thesis. Biological stress responses were measured at different levels of organisation: two sub-cellular responses (lipid peroxidation and cholinesterase activity); three measures of macroinvertebrate tolerance to water quality impairment; five measures of community composition; three measures of community richness; and a surrogate measure of ecosystem function (functional feeding groups). Weight-of-evidence methodology was utilised to assess, integrate and interpret the chemical and biological evidence, and at its conclusion, determined no effect on the in-stream biological community of the Balfour River downstream of laundry washing activity.

Text in English with summary and keywords in English and Afrikaans / The International Organization for Standardization - ISO 14001 environmental standard addresses facets of environmental performance. The implementation of ISO 14001:2015 is aligned with various risks and opportunities, the identification and addressing of which is key in the successful implementation of the ISO 14001:2015 certification. The Durban region is a pollution ‘hotspot’ within KwaZulu-Natal. Assessment of the opportunities and risks of ISO 14001:2015 implementation within the region is key as it can potentially assist with proactive mitigation of risks and the effective utilization of opportunities. The aim of the study is to understand SHERQ (Safety, Health, Environmental, Risk and Quality) managerial perspectives of opportunities and risks of ISO 14001:2015 implementation in Durban, KwaZulu-Natal. The following objectives were outlined: To identify ISO 14001 implementation opportunities and risks internationally and nationally by means of an extensive review of international as well as national literature sources, to generate an evaluation framework to assess SHERQ managerial perspectives of risks and opportunities of ISO 14001:2015 implementation within Durban and to analyse SHERQ managerial responses to the ISO 14001:2015 implementation risks and opportunities within the Durban region. The methods included identifying primary opportunities and risks in ISO 14001:2015 from the literature review through an evaluation framework, thereafter, presenting these in questionnaires distributed among SHERQ managers in Durban via email and LinkedIn. Of 62 questionnaires distributed, 42 participants responded. The respondent’s perspectives were assessed through SPSS identifying key risks and opportunities. Objective 1 was achieved through the literature review in which ISO 14001 implementation risks and opportunities were identified. Objective 2 was achieved by generating the evaluation framework which assimilated implementation risks and opportunities. Objective 3 was achieved through the analysis of the responses of respondents to ISO 14001:2015 implementation risks and opportunities. Study results showed that, in line with international reports, 57.2% of all respondents agreed that the maintenance costs of compliance to the standard are high and 76.2% of respondents shared the perspective that company resources are better managed. Respondents were more agreeable to positive statements, indicating opportunities outweighing the risks. Furthermore, despite the risks, there are opportunities from an industry perspective such as increased investor inputs and increased top management involvement. A follow up study is recommended in the Durban region addressing ISO 14001 implementation risks, opportunities, and their investment impacts in order to further hone in on the organizational implications of certification. From an academic standpoint, multiple studies have posited that ISO 14001:2015 implementation resulted in improved financial outcomes but are associated with high implementation costs and it is recommended that a critical cost versus profits analysis into ISO 14001:2015 implementation be undertaken in the Durban region. / Die Internasionale Organisasie vir Standaardisering se ISO 14001-omgewingstandaard spreek fasette van omgewingsprestasie aan. Die implementering van ISO 14001:2015 is gerig op verskeie risiko’s en geleenthede, en die identifisering en aanspreek hiervan staan sentraal tot die suksesvolle implementering van die ISO 14001:2015 - sertifisering. Die Durban-streek is ʼn besoedlingsbrandpunt in KwaZulu-Natal. Evaluering van die geleenthede en risiko’s van die implementering van ISO 14001:2015 binne die streek is van kardinale belang, aangesien dit moontlik kan help met die proaktiewe vermindering van risiko’s en die effektiewe benutting van geleenthede. Die doel van die studie is om SHERQ-bestuursperspektiewe van geleenthede en risiko’s van ISO 14001:2015-implementering in Durban, KwaZulu-Natal, te begryp. Die volgende doelwitte is uiteengesit: Om ISO 14001-implementeringsgeleenthede en risiko’s internasionaal en nasionaal te identifiseer deur middel van ʼn uitgebreide oorsig van internasionale sowel as identifiseer deur middel van ʼn uitgebreide oorsig van internasionale sowel as nasionale literatuurbronne; om ʼn evalueringsraamwerk te genereer om SHERQ-bestuursperspektiewe van geleenthede en risiko’s van die implementering van ISO 14001:2015 te evalueer, en om SHERQ-bestuursreaksies op die ISO 14001:2015-implementeringsrisiko’s en -geleenthede te ontleed. Die metodes het ingesluit die identifisering van primêre geleenthede en risiko’s in ISO 14001:2015 vanuit die literatuurbeoordeling deur middel van ʼn evalueringsraamwerk, waarna dit in vraelyste wat via e-pos en LinkedIn onder SHERQ-bestuurders in Durban versprei is, uiteengesit is. Van die 62 vraelyste wat versprei is, het 42 deelnemers geantwoord. Die perspektiewe van die respondente is beoordeel deur middel van SPSS se identifisering van die belangrikste risiko’s en geleenthede. Doelwit 1 is bereik deur middel van die literatuuroorsig waarin ISO 14001-implementeringsrisiko’s en -geleenthede geïdentifiseer is. Doelwit 2 is bereik deur die evalueringsraamwerk te genereer wat implementeringsrisiko’s en -geleenthede geassimileer het. Doelwit 3 is bereik deur die antwoorde van respondente op ISO 14001:2015 implementeringsrisiko’s en -geleenthede te ontleed. Studieresultate het getoon dat, in ooreenstemming met internasionale verslae, 57,2% van alle respondente dit eens was dat die onderhoudskoste van die nakoming van die standaard hoog is en dat 76,2% van die respondente die perspektief gedeel het dat bronne van die maatskappy beter bestuur word. Respondente het meer met positiewe stellings saamgestem, wat daarop dui dat geleenthede swaarder weeg as die risiko’s. Ten spyte van die risiko’s, is daar ook vanuit ʼn bedryfsperspektief geleenthede, soos verhoogde beleggersinsette en verbeterde hulpbronbestuur. ʼn Opvolgstudie word aanbeveel om ISO 14001-implementeringsrisiko’s en geleenthede en die beleggingsimpak daarvan aan te spreek. Vanuit ʼn akademiese oogpunt het veelvuldige studies aangevoer dat die implementering van ISO 14001:2015 verbeterde finansiële uitkomste tot gevolg het, maar dat dit met hoë implementeringskoste gepaard gaan, en dit word aanbeveel dat ʼn kritieke koste-versus-wins-analise in die implementering van ISO 14001:2015 in die Durban-streek onderneem word. / Environmental Sciences / M. Sc. (Environmental Management)