Masters Degrees (Occupational and Environmental Health)

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Ambient sulphur dioxide (SO2) and particulate matter (PM10) concentrations measured in selected communities of north and south Durban.
(2006) Gounden, Yoganathan.
The industrial basin in the south of Durban is an area of ongoing contention between the residents and major industries, regarding environment health issues especially poor air quality resulting from industrial air pollution. This region is a result of poor urban planning that began in the early 1960's which saw rapid industrialisation alongside expanding communities, which has now resulted in a major environmental dilemma for the city of Durban, eThekwini Municipality. Durban is seen as a key area of growth in South Africa: it has the busiest harbour on the continent; it is a regional hub of the chemical industry and a major motor and metal manufacturer centre; and Durban's population continues to grow at ~4% per annum, all of which are destined to have significant environmental impacts. As part of a large epidemiological study and health risk assessment in this industrial basin, particulate matter smaller than 10 microns (PM10) and sulphur dioxide (S02) were measured in seven community sites across Durban: four in the South, (Wentworth, Bluff, Merebank and Lamontville) and three in the north (Kwamashu, Newlands East and Newlands West). The south sites are located in an industrial basin near two petroleum refineries and a paper mill, while the north comparison sites are ~25 km North West from major industries in the Basin. 24 hour PMIO samples were collected gravimetrically every day during four, three-week intensive phases and thereafter every 6th day using high, medium and low volume samplers. S02 was monitored every 10 minutes with active continuous analysers (European monitor labs and API) according to internationally accepted methods. Rigorous quality assurance methods were followed for both pollutants. S02 followed a distinct spatial distribution where the mean difference in S02 concentrations between the southern and the northern region was 6.7 ppb, while for PMIO similar concentrations were found across all sites with the highest mean concentration at Ngazana in the north (59 Ilg/m3) > Assegai in the south (~58 Ilg/m3) with all other sites ~ I to 10 Ilg/m3 less in mean concentration. S02 diurnal variations display two maxima from 5:00AM to 10:00AM being repeated in the latter part of the day from 20:00PM to 24:00PM. Seasonal pattern of PMIO and SOz to a lesser extent, display very similar mean variations for all sites - the highest levels seen in the colder months of May; June, July of 2004 and 2005. Weak to strong intersite correlations were found for SOz ranging from 0.16 to 0.22 among the south sites; 0.06 to 0.64 among the north sites, while PM10 ranged from 0.73 to 0.88 among the south sites and 0.86 to 0.91 among the north sites. A cross regional correlation of PMIO by sites displayed a moderate to strong correlation ranging from 0.73 to 0.88, while intrasite SOz with PMIO correlations displayed weak to moderate correlations from 0.35 to 0.53. Meteorological conditions wind speed, temperature, pressure and humidity differed across Durban. The difference in temperature and humidity between "summer" and "winter" was on average, approximately 7 °c and 10-15% respectively. These temperature and humidity patterns closely track the increase in SOz and PM10 during "winter" explaining the effects of winter inversions on pollutant levels. Also of interest is the variability of meteorological parameters between south and north Durban with the two regions being 35 km apart. Meteorological conditions impact differently on each pollutant e.g. rain is more likely to decrease PMIO concentrations than it would SOz In general relationships between pollutants and meteorological parameters differ on a site-bysite basis. For instance, wind direction at Assegai increases SOz levels whereas wind direction at Ngazana decreases SOz levels. Another independent variable that proved to be a consistent and important predictor for SOz and PM10 across most sites was the previous day's pollution events; this was a much stronger predictor for PM10 rather than SOz. These findings suggest that pollutants are not fully removed from the atmosphere during a 24 hour period and that the previous day's pollution levels will contribute to current levels, a finding that has important implication when implementing early warning pollution systems as envisaged for the Durban South Basin.
Indoor and outdoor environmental assessment of Durban block hostels : an internal evaluations on exposure measures and outcomes of self supported health and well-being in hostels.
(2007) Buthelezi, Sikhumbuzo Archibald.; Gqaleni, Nceba.
Hostel dwellers form a larger part of the urban population in South Africa (Ramphele, 1999). These hostels were initially created as temporal arrangement for African men moving from rural to urban areas seeking for employment. Due to housing shortage in urban areas they eventually became permanent residential accommodation. However, observations into the environmental conditions in these hostels have raised concerns about the health and well being of residents and neighbouring communities. The area of study was selected on the basis of the current depleted living conditions due to mismanagement of facilities provided by both the occupants and the hostel administrators. The study was a cross sectional descriptive study involving all three Durban Metropolitan block hostels. Assessing (i) the quality of block hostel environment (indoor and outdoor) through visual inspection (walkthrough), (ii) the exposure measures and outcomes (biophysical environment assessment) by means of questionnaire survey, air testing and microbial identification. Sixty three (63) hostel inventory were completed, followed by the administration of 450 questionnaires, and 646 surface and air samples were collected in the indoors of the selected hostel blocks including the control outdoor samples. The demographic profile of the hostel dwellers in the selected hostel blocks revealed that in the five bed type dormitories the habitable space per individual was 3 m 2 to 3.8 m2. Whilst in the ten bed type dormitories the habitable space per individual was 3.3 m 2 to 3.6 m2 . This was not even close to the World Health Organization suggested habitable space of 12 m2 (WHO, 2000) and was therefore regarded as overcrowding. Lack of access control in the hostels exacerbated by the socio-economic demands of the living environments, e.g. unemployment, was to blame for overcrowding. This overcrowding of the hostels was overloading the services, causing enormous number of blockages and bursts of wastewater pipes resulting in the system not functioning. This situation resulted in the accumulation of dampness in the indoor environment, and hence creating conditions favouring the growth of indoor mouldiness in the buildings. This was further supported by evidence that 47% of the occupants in the selected hostel blocks were experiencing respiratory symptoms and 53% experiencing non-respiratory symptoms. The most recorded respiratory symptoms were pulmonary tuberculosis (14.3%), chest tightness (12.2%), sore and dry throat (7%), sinus congestion (7%) symptoms. Whilst the most recorded non-respiratory symptoms were headache (11.5%), dry and itchy skin (11.5%), stomach upset (6.3%) and fatigue (3.6%). Forty five percent (45%) of the respondents were current smokers and 80% of them had a tendency of smoking indoors. The results of the surface and air samples indicated that the level of indoor mould growth in the selected hostel blocks was at 37, 24%. Surface moulds were at 58% and airborne spores were at 42%. Statistical analysis of data revealed a significant relationship between exposure factors and outcomes in the 5, 10 and 15-bed type dormitories. Incidence Risk Rate (IRR) and the p-value (p . 0.01) were used to determine relationships between exposure factors and outcomes. Certain factors were very much supportive in the development of selfreported symptoms in the selected hostel blocks of the three hostels under certain circumstances and these were the hygiene state of the building, leaking pipes, smoking habits and total mea and dg surface moulds. At all levels of the analysis the hygiene state of the building was very much supportive in the development of self-reported symptoms. Other exposure factors were not supportive at all, for example, structural defects, bed-types, different floor levels and participants' perception of overcrowding. A review process of the role of legislation in controlling the adverse health effects revealed that certain aspects of the legislation relating to building standards requirements, sanitation requirements, ventilation requirements, space and density requirements, and air quality standards requirements were violated. Therefore, the findings of the study recommended that a proper management plan must be developed to enhance living standards. This plan shall include a routine maintenance of the building structures, the development of a culture of self-care, as well as access control in the hostels. In addition to that where there are signs of visible moulds on walls and ceilings adequate control measures are highly recommended using commercially available measures in order to provide a healthy living environment. In conclusion is the adoption of a compliance policy towards legal requirements pertaining to building standards as defined in the National Building Regulations Standards Act (Act 103 of 1977). This study has showed that necessary iii steps need to be taken in South Africa in order to combat this problem. Further research need to be taken in order the inhabitable buildings to be better living environment improving the existing building structures.
Survival and rehabilitation following acute stroke.
(1986) Dewar, Sandra Ruth.; Arbuckle, Derek Dennis.; Bill, Pierre Louis Alfred.
The outcome of acute stroke in 210 White adult patients admitted to Addington Hospital, Durban in 1983 and 1984 was investigated by means of retrospective case-note review. In addition, the level of functional independence of 35 people who, at the time of this study, were survivors of an initial acute stroke was assessed through household survey. The study was considered relevant and worthwhile for several reasons: 1. Stroke is an important contributor to morbidity and mortality in Whites in South Africa, however, l i t t l e information is available in respect of the outcome of sufferers of stroke who were admitted to the study hospital. 2. Knowledge of the needs of survivors of acute stroke is necessary if appropriate health care is to be provided. 3. Few community studies have been done in South Africa in which the status of stroke survivors has been established. The principle aims of the study were therefore: 1. To establish the survival of patients with acute stroke who were admitted to the study hospital. 2. To determine in survivors of an initial stroke their residual functional loss and hence to identify the supportive health care needs of this group. The most important findings of the study were as follows: 1. Of the 286 stroke admissions identified through the hospital's medical record retrieval system, stroke diagnosis according to the study definition could be confirmed in only 210 (73.4%) cases due to misplaced files or miscoded diagnoses. The need for improvement in the method of recording, storing and retrieving of patient information is indicated by these findings. The overall hospital fatality rate for stroke was 54%. Mortality was highest in the first week after admission (71%). The number of males and females, in respect of whom a final diagnosis of stroke was attributed, was almost equal. A significant difference (p < .000 2) in respect of age was noted between the sexes. The mean age of onset of stroke was 62.9 and 70.0 years for males and females respectively. The major diagnostic categories (haemorrhagic or occlusive) of stroke could only be ascertained in respect of 30% of cases. This was due to incomplete recording of clinical findings, and possibly, due to the absence of resident brain-scanning facilities at the time. Analysis of the results of the household interviews indicated that:-( I ) Of the 35 patients interviewed 13 (37%) were found to be fully independent in self-care and were mobile outside of the home. (ii) The patients' potential for improvement in an appreciable number of cases had been under-estimated by the hospital staff. Patient adjustment following hospital discharge appeared adversely affected by.-(i) Inadequate preparation for discharge, especially where patients were returning to their own homes. (ii) Inadequate explanation given to patients and their families of the meaning and implications of stroke. (iii)The non-involvement of the family during the period of hospitalization. (iv) The absence of appropriate follow-up after discharge. Stroke onset was a traumatic experience in all cases. Amongst the most important reasons given for reduced life-satisfaction post stroke were confinement to the home, reduced independence and unresolved loss (eg death of spouse, forced retirement). 8. In some cases it was f e l t that social isolation, general ill-health and old age were more significant problems in the lives of patients than the stroke itself. The advent of stroke merely exaggerated these problems. 9. The advantage of administering a standardized functional assessment at intervals during the rehabilitation of the patients became increasingly clear as the study progressed. It is proposed that functional assessment be considered as important as clinical assessment in the management of stroke patients. 10. Recommendations have been submitted concerning rehabilitation and the provision of supportive services for stroke patients. As the role of the nurse in short and long-term care is central to successful stroke outcome, emphasis has been placed on her role in the team. The main conclusions formulated in the study were:-1. Mortality from stroke is high but in survivors an appreciable proportion maintained functional independence. 2. Preparation of patients and their families is important to adjustment following discharge from hospital. 3. Supportive services are important to the maintenance of the stroke patient in the home environment. 4. A team approach, consisting of a wide range of health professionals is appropriate to the management of stroke. 5. Functional assessment is an important component of the clinical examination and should be done prior to discharge and subsequently at regular intervals to assess the patient's competence to exist in the current domestic environment.
A review of dispensing in South Africa.
(1986) Cassimjee, Mohammed Hoosen.
The dispensing Medical Practitioner has become topical since 13B4 . Dn this issue, much confusion and ignorance prevails, both amongst members of the medical and allied professions and in the public mind. This study was undertaken to demonstrate some aspects of dispensing of medicines in South Africa and to cansider the implications arising out of the application of legislation governing such dispensing of medicines by family practi tioners. The main objectives of this study were: CaD To identify and ascertain the opinions and policies of all those who are involved and concerned with the dispensing of medicines. Cb) To determine the implications of all the legislation governing the dispensing of medicines on: 1. patient care 2. the dispensing of medicines by doctors Cto their patients}. Information was gathered from a questionnaire sent to service/ consumer groups; from literature review of journals; publications and gazettes; and from legal consultations. The results of the study indicated that: C13 Professional Associations such as, Medical Association of South Africa, the Pharmaceutical Society as well as statutory bodies such as the South African Medical and Dental Council and the Pharmacy Council are concerned with issues such as 'trading in medicine ' and 'profiteering '. Inadequate patient care resulting from the physical, financial and economic hardships suffered by a majority of patients are issues which appear not to have been addressed by these bodies. CE) The fundamental issues of "what is in the best interest of the patient " appears to be ignored in legislation pertaining to dispensing. C33 Dispensing to patients became difficult due to the impractical stringent restrictions imposed by the legislation governing dispensing of medicines. C4D The dispensing of medicines by a doctor is less timB consuming, more convenient and cheaper for the patient as well as for the Sick Benefit Funds. The results were discussed with respect to their theoretical and practical implications and the conclusion reached was that the dispensing legislation presently designed for first world communities, became totally impractical when applied to third world communities, and that most doctors dispense medicines in response to the needs of the individual communities they service. Further research possibilities and recommendations were suggested in order to gain a greater understanding of the dispensing issue, which hopefully will assist to improve the quality of health care and also ensure the best possible advantage for the patient.
Profile of sickness absenteeism at the Consul Glass factory, Clayville, Midrand, 2004.
(2008) Suleman, Fatima.; Naidoo, Saloshni.
INTRODUCTION Sick leave absenteeism is a recognized problem in all work sectors. The financial impact of sick leave has been well-documented. A profile of sick leave records can establish the extent of the sick leave problem in a workplace, the associated and predisposing factors for sick leave and the patterns of sick leave amongst workers. A baseline profile of the sick leave patterns in a workplace should be a preliminary step toward developing a programme aimed at the improvement of workers' health and attendance at work. AIM OF THE STUDY The aim of this study was to profile recorded sick leave for 2004 amongst permanent workers at the Consul Factory in Olifantsfontein, Midrand, Johannesburg in order to make recommendations to management. METHODS This was a cross-sectional study using a retrospective review of sick leave records of permanent workers at the Consul Glass factory for 2004. Information gathered included the demographic profile of workers who recorded sick leave, the frequency of sick leave, associated factors for sick leave, health care choices of workers with sick leave and the reasons for sick leave. Descriptive and analytic statistics have been presented. RESULTS • Workers over the age of fifty years had sick leave of longer duration compared to those younger than 50 years old (p<0.05). The median hours taken off for sick leave was higher in the male subgroup compared to the female subgroup of workers in the study population (p<0.05); • Workers from the production areas had more sick leave episodes for the year than workers from the non-production areas (p<0.05). Workers with bronchitis working in the production areas of the factory, had longer duration of sick leave compared to workers with bronchitis working in the nonproduction areas of the factory (p<0.05); • Workers on a variable shift schedule took more sick leave on days of the week that were unlinked to weekends and public holidays (p<0.05).A longer duration of sick leave occurred with certified sick leave compared with self reported sick leave (p<0.05); • In the study population, the majority were not medical aid members. Medical aid members had a longer duration of sick leave per episode compared to non-medical aid members (P<0.05); • Respiratory tract infection was the most common reason for sick leave. Of the ten most common reasons for sick leave, there was a significant difference in the mean number of hours of sick leave taken per episode for dental treatment and backache (p<0.05); • There was a significant difference in the mean number of hours of sick leave recommended by the four different sources of sick notes (p<0.05); • There was a significant association for worker interviews/counselling by the Human Resources' Department official and the worker having had four or more episodes of sick leave for the year (p<0.05). CONCLUSION The profile of sick leave at this company identified important associations with sick leave patterns. These significant findings provide management with baseline information, which can be used for the development of workplace interventions to address the taking of sick leave at the Consul Glass factory.
Epidemiological and genetic risk factors associated with asthma among children in the south Durban region, KwaZulu-Natal.
(2008) Reddy, Poovendhree.; Naidoo, Rajen.; Naidoo, Richard.
Several genes are associated with an increased susceptibility to respiratory diseases, including asthma, which may be exacerbated by ambient air pollution. These genes include the Gluthathione-S-Transferase family (GSTM1 and GST1l) and the NAD(P)H quinone oxidoreductase (NQO1). This, the first genetic epidemiological study conducted in Sub-Saharan Africa had 2 main objectives: I) to evaluate whether the above genotypes confer susceptibility to asthma and related phenotypes; and 2) to investigate if polymorphisms in these genes known to modulate the response to or protect from epithelial oxidative damage modify pulmonary response to ambient air pollutants. A total of 369 schoolchildren from seven primary schools in a heavily industrialized region of south Durban and a demographically similar area in north Durban, Kwa-Zulu Natal, South Africa during the period May 2004 - October 2005, participated in the study. DNA was extracted from whole blood using the GENTRA Puregene kit. Genotyping for the GSTM1 (null vs present genotype) was done using multiplex PCR while the GSTP1 (I1e105Val; AA>AG/GG) and the NQO1(Pro/Ser; CC>CT/TT) genotypes were determined using real time PCR and Taqman probes (Applied Biosystems). Persistent asthma and asthma of "any severity" was determined by questionnaires based on the ATS and BRMC questionnaires. Positive atopy was determined by at least one positive skin test reaction to the seven allergens tested. Other health assessments included spirometry, methacholine challenge testing and four cycles of three-week serial peak flow measurements. Acute respiratory measures included within day variability in FEV1 and PF and the lowest valid values on a given day. SO2. NO2, NO and PM10 were measured over a year using ultraviolet fluorescence, gas-phase chemiluminescence and gravimetric methods respectively. STATA (version 9, College Station, TX, USA) was used for data analysis. Multiple logistic models and Pearson's chi-squared tests were used to evaluate the association between asthma, BHR, atopy and genotype. Covariate-adjusted generalised estimating equations (GEE) with lags of 1-5 days were used to evaluate genotype effect modification of exposure-response. The GSTM1 gene deletion (GSTM1null) was detected in 28.9% of the study population while the distribution of GSTP1 AG/GG and the NQO1 CT/IT polymorphisms were 64.9% and 36.0% respectively. Multiple regression with the adjustment for relevant covariates indicated that individuals carrying one or more copies of the GSTP 1 minor allele had a statistically significant risk for persistent asthma. GSTM1 and NQO1 genotypes showed no significant association with any of the respiratory outcomes tested. However, we found a protective effect for those individuals carrying the GSTM1null genotype and at least one Ser allele (NQO1 CT/TT) for persistent asthma and marked BHR (OR = 0.7, Cl: 0.3-1.5 and OR= 0.3, Cl: 0.0-1.9 respectively). This protective effect is consistent with the role of NQO1 in metabolic activation. Children from the south schools had almost twice the risk of persistent asthma (OR=2.0, Cl: 1.2-3.2, p<.005) and 3 times the risk of BHR (OR=3.5, Cl: 1.4-8.4, p<.005) than those from the schools in the north. Based on symptoms, 20.4% of children from the random sample had persistent asthma and 10.3% had marked BHR (PC20< 2mg/ml). The GEE model results were consistent with modification of air pollutant-pulmonary function relationships by oxidative stress associated genotypes. Statistically significant gene*environment interactions with NO2, NO, and PM10 using FEV1 and PEF outcomes in the expected direction were more frequent for GSTP1 AA and NQO1 CC genotypes (interaction p-values <0.05). There were very few gene*environment interactions for SO2 and any of the 3 SNPs tested. The most striking finding in our study was that pollutant exposure, especially oxides of nitrogen and PM10, even at levels below the recommended limits of South African guidelines, is associated with poorer lung function and that this association is significantly modified by an individual's genotype, particularly the GSTMlnull, GSTPIAA and NQOICC genotypes. Children with the GSTMlnull GSTPI AG/GG, GSTPI AG/GG NQOI CC and GSTMlpos NQOICC gene-gene combinations showed a significant interaction with NO2, NO, and PM10 with decrement in lung function measures. The increased risk to air pollution conferred by the GSTPI and GSTMl genotypes may have clinical and public health importance because this variant is common in most populations. The findings suggest that the risk of developing respiratory symptoms is increased when genetic susceptibility is included with environmental exposures. Our models suggest significant gene*environment interactions i.e the response to the level of air pollutants, as indicated by variability in pulmonary function measures, is modified by genotype. The heightened allergic airway response may be a consequence of a decreased capacity to mount an effective cytoprotective response to oxidative stress. Studying genes may inform us about the biology of asthma which may lead to new therapies or preventative strategies. This study supports the importance of further investigation on these and other genotype variants involved in oxidative stress and respiratory phenotypes in larger cohorts.
An evaluation of the exposure of students and staff to formaldehyde vapour in the human anatomy laboratory of the Faculty of Medicine, University of Natal.
(1996) Oosthuizen, Jacques de Villiers.; Raynal, Anne L.
The aims of the study were to review the literature on the currently known adverse health effects of formaldehyde vapour exposure, to measure environmental formaldehyde levels before and after engineering controls were implemented, to measure symptoms of formaldehyde exposure when compared to non - exposed controls and to evaluate the effectiveness of engineering controls in reducing the symptoms associated with formaldehyde vapour exposure in anatomy students at the Faculty of Medicine, University of Natal. Pre and post intervention environmental monitoring surveys were conducted over the period July 1993 to September 1995 in the aforementioned Human Anatomy Laboratory using passive diffusion badges which were then analyzed by an approved laboratory in Johannesburg. Ambient air temperature, humidity and ventilation rates were measured simultaneously using appropriate instruments. Self-administered questionnaires, relating to the symptoms of exposure to formaldehyde vapours, were obtained from all anatomy students over a two year period before or after as well as during their exposure to the laboratory environment, as well as from all exposed staff members (including their control group). Nasal epithelial scrapings of staff members and a control group were subjected to cytological examination by the Cytology Department of the Provincial Pathology service, at the pre - intervention phase. The environmental monitoring data of 1993 and 1994 indicated that the ambient levels of formaldehyde vapour exceeded the American (ACGIH) Threshold Limit Value (TLV) and thus posed a potential health risk to students and staff, this was due to inadequate ventilation in the Human Anatomy Laboratory. An intervention in terms of ventilation controls was implemented and proved to be effective in reducing formaldehyde vapour levels and reported symptoms in the cohorts studied, comparing each group to themselves, however, the reported symptom levels did not drop significantly in the group exposed after the intervention compared to the group surveyed at the pre - intervention phase. Whether this reduction is sufficient to prevent long term health effects such as neoplasms and sensitization remains to be established. Hence it is recommended that alternative control methods should be considered.
Tuberculosis in coal mine workers in Mpumalanga.
(2009) Mphofu, Obed.; Naidoo, Rajen.
Introduction Pulmonary tuberculosis (TB) is a disease which is both curable and preventable, with recognised complications such loss of lung function and progressive massive fibrosis (PMF). It is a major cause of pulmonary disability and mortality in the South Africa mining industry. Tuberculosis has a high social and economic cost, both for the individual concerned and for the industry as a whole. However, notwithstanding the extensive literature on TB in the mining industry, given the size and economic importance of coal mining in South Africa, there is surprisingly scanty information available on TB and other occupational lung diseases in coal mines. A strong correlation was reported in Canada, the USA and China between coal usage and TB. This highlights the possibility of the direct impact of coal usage on TB. Although black miners have historically done jobs with the highest exposure in the coal mining industry, there have been remarkably few studies reporting the prevalence of TB and the exposure response relationship in black coal miners in South Africa. Dust exposure in coal mines is a risk factor for occupational lung diseases such as coal workers' pneumoconiosis (CWP), chronic obstructive airways disease (COAD) and lung function deficiency. However, there are still doubts and debates about the risk in such work of tuberculosis. The aim of this study was to fill the gap in the literature by determining the prevalence and exposure response relationship of TB to coal dust exposure. Objective To determine, within a sample of coal miners: . Prevalence of tuberculosis (TB) . Prevalence of coal workers' pneumoconiosis and past TB . Association of outcome variables with exposure variables and underground coalmine workers' exposure as compared to that of surface workers . Association of TB with coal workers' pneumoconiosis and past TB . Exposure response relationship of TB, coal workers' pneumoconiosis and past TB to respirable coal dust. Method A cross-sectional study of 344 employed black male coal miners at a coal mining complex with fourteen mine shafts at Secunda in Mpumalanga, was done. The records from 1 January 2000 to 31 December 2005 were reviewed. The main outcome measure was the prevalence of current TB in coal miners. The sample consisted of 220 underground and 124 surtace coal miners. The exposure variables considered were lifetime mean exposure level (LMEL) (mgim3), cumulative dust exposure (CDE) in mg-years/m3, and coal mining years. Information was collected from multiple sources including hospital files, surveillance records and medical records, and crossvalidated with the information from the human resources department. Information was collected on the demographic profile, exposure, underground or surface work, area of work, smoking history, HIV status from medical records, dust exposure intensity, length of service, TB diagnosis and the methods of diagnosis and outcome of the treatment, and previous TB and CWP. Participants with current TB were either sputum culture positive or sputum culture negative TB. Results The mean age of the sample was 45.2 years, (range 2844 years; SD = 8.2).The mean duration of service was 16.1 years (range 4.1-27.7 years; SD 5.9). There were 34 (9.9%) cases of current TB in total, of which 31 were underground coal miners and three were surface coal miners. The prevalence of current TB reported by this study was 9.97o, with a mean age of 46J years and length of service of 16.2 years. The prevalence of current TB among the underground and surface workers was 14.1o/o and 2.4o/o rcspectively. The prevalence of CWP was 3.8o/o, with a mean age of 51.3 years and a mean length of service of 2Q.l years. The prevalence of past TB was also 3.8o/o, with a mean age and length of service of 44.9 and 1 6. 1 years respectively. Underground coal mines workers' exposure to coal dust was high, with a lifetime mean exposure level (LMEL) and cumulative dust exposure (CDE) of 2.4 mg/m3 and 33.4 mgyears/ m3 respectively. The difference in LMEL and CDE among underground vs. surface workers was significant, with underground exposure being higher than surface exposure, namely p<0.001 and p<0.001 respectively. The difference in length of service between underground and surface participants was not significant. The difference in exposure to coal dust (LMEL and CDE) among participants with current and previous TB, compared to those without current and previous TB, was statistically significant, p<0.008 and p<0.04. The difference between the coal dust exposure indices (LMEL, CDE exposure duration) for participants with and without CWP was significant. However, the difference between participants with current TB and previous TB compared to those with non-current TB and without previous TB in age and length of service years was not significant. This also applied to HIV status and smoking: the difference between participants with and without current TB was not significant. There was a strong significant association of underground mine work with current TB, with a prevalence odds ratio (POR) of 6.62 (p<0.001).This showed that the association of exposure to coal dust with current TB was strong and significant as underground mine workers were exposed to higher coal dust concentrations than surface workers. Workers with current TB were more likely to have co-existing CWP, with a POR of 1.7 (95Vo Cl:0.f7.1). The exposure-response relationship of LMEL and CDE in participants with current TB and CWP was significant. A significant trend was observed of increasing of LMEL and CDE with an increase in the prevalence of current TB, CWP and past TB. Conclusions There was a possible dose response relationship between coal dust exposure and the risk of development of pulmonary TB. The study showed that coal dust exposure was associated with pulmonary TB, and a dose response relationship with the trend of increasing coal dust exposure. lt has been shown that there is a more significant and stronger association of underground coal mine work with current TB than there is in surface work. This study has shown a significant exposure response relationship in the exposure indices (CDE and LMEL), age and length of service for CWP. This study found a high prevalence of pulmonary TB of 9.9% in black migrant coal mine workers who historically held jobs in the dustiest areas in the mining industry. The limitations of the study include the use of cumulative exposure calculated from current exposure, and the secondary healthy worker effect or survivor workforce. Dust control and HIV/AIDS programmes should be an integral part of a TB and occupational lung disease control strategy in the mining industry.
Occupational exposures and chronic obstructive pulmonary disease : a hospital-based case-control study.
(2009) Govender, Nadira.; Naidoo, R. N.
Aim The aim of this study was to determine the contribution of occupational exposures to the burden of Chronic Obstructive Pulmonary Disease (COPD) among a sample of hospital based patients. Methods Cases (n=110) with specialist physician diagnosed COPD from the three public sector specialist respiratory clinics in KZN and controls (n=102) from other nonrespiratory chronic ailment specialist clinics at the same institutions were selected. An interviewer administered questionnaire and exposure history was obtained for each participant. In addition, a valid lung function test was obtained for each case. Data was analysed using STATA version 10. Multivariate regression models were developed to examine the relationship between COPD and occupational exposures while adjusting for age, sex, smoking and previous history of tuberculosis. The relationship of FEV1 and occupational exposures, adjusted for age, height, previous history of tuberculosis and smoking history, was investigated among cases. Results Cases and controls were similar with respect to age and sex distribution. Cigarette smoking differed significantly between cases and controls with a larger proportion of cases having ceased to smoke compared to controls (72% vs 46%, p<0.01). A higher proportion of controls reported employment in administrative, managerial and quality control positions (21.3% vs 12.0%, 7.7% vs 2.6% and 5.4% vs 0.3% respectively). Employment in the construction and shoe manufacturing industries was reported more frequently by cases (10.3% vs 3.2% and 10.0% vs 4.9% respectively). Cases were more likely than controls to have been exposed to dust (72% vs 28%, p<0.001) or to chemicals, gas or fumes (74% vs 25.5%, p<0.001) and reported exposure durations 3-4 fold higher than that of controls (p<0.001). Dust and chemical, gas or fume exposure was associated with an increased odds of developing COPD. Exposure to dusts (OR 7.9, 95% CI 3.9-15.7, p<0.001), chemicals, gas or fumes (OR 6.4, 95% CI 3.2-12.8, p<0.001) were significantly associated with odds of developing COPD. In addition, previous history of tuberculosis, as well as smoking were associated with an increased odds of COPD (OR 5.7, 95% CI 1.2-27.4 p<0.001 and OR 6.4, 95% CI 2.3-17.7, p<0.001). Discussion and Conclusion This is one of the first hospital based case-control studies looking at occupational contribution to COPD undertaken in South Africa. In this sample of participants, strong associations were observed between self-reported occupational exposures to dust, and chemicals, gas or fumes, and physician’s diagnosis of COPD. The study also demonstrated a strong association between smoking and previous history of tuberculosis, and risk of COPD. The findings suggest that persons with known occupational exposures to respiratory irritants should be monitored to detect the onset of respiratory ill-health and that preventive strategies should reduce exposure to these agents in the workplace.
Toxicological analysis of house dust collected from selected Durban residental buildings.
(2009) Nkala, Bongani Alphouse.; Gqaleni, Nceba.
Indoor air quality is described as the chemical, physical and biological characteristics of air in a residential or occupational indoor environment. In residential settings, there are many contributions to indoor pollution levels namely; human activities, biological sources and outdoor air. There has been increased focus on house dust due to its potential to contain biological and chemical pollutants in indoor environments. These have the potential to cause harm to human health. The purpose of this study was to conduct toxicological analysis of house dust collected from inside selected Durban residential buildings. The objectives of this study were to isolate, identify and quantify mould occurrence in house dust samples; to measure the occurrence of heavy metals (arsenic, lead and mercury) in house dust; and to analyse the cytotoxicity of house dust on human lung bronchus carcinoma epithelial line (A549) and human lung bronchus virus transformed epithelial cell line (BBM). One hundred and five house dust samples were obtained from households that participated in the South Durban Health Study. In each home, a sample of settled dust was collected, using standardized protocols, then sieved and individually packed into polystyrene bags. The samples were taken from three surface areas namely; living room couches, bed mattresses, and carpets. Well documented methods were used for the isolation, identification and quantification of mould. The samples for heavy metals analysis were sent to Umgeni Water (chemistry laboratory, Pietermaritzburg) where standardised methods were used. Human cell lines were treated with five different dilutions of each house dust extract. Cell viability was assessed using the MTT assay. Toxic effects of house dust extract were analyzed, following house dust extract treatment and cells were stained with double dye (annexin-V- and propidium iodide) and analysed with flow cytometry, and fluorescent microscope. Cytokines were analysed by Microbionix (Neuried, German) using a Luminex®100 plate reader for multiplex human cytokines analysis. There were (n=128) mould types isolated and (n=105) were identified, of which (n=10) were predominately isolated moulds. This was further confirmed by Allerton Provincial Laboratory in Pietermaritzburg. Among the isolated genera in all three surface areas, Rhizopus spp and Penicillium spp were widely distributed throughout surface areas in greater proportion. The overall highest mean which was reported in this study and expressed in colony forming unit per gram (CFU/g) for Penicillium spp ranged (3400 - 62316 CFU/g) obtained from living room couches, followed by Rhizopus spp (5200 - 15990 CFU/g). The mould results were compared with the South African Occupational Health and Safety Act (OHSA) 85 of 1993 as amended suggested guidelines of 1,000, 000 CFU/g. The findings of this study suggest the moulds in the homes studied were below the suggested guideline. However, this does not imply that the indoor conditions are unsafe or hazardous. Instead, the findings act as an indicator of moulds presence indoors. The type of airborne mould, its concentration and extent of exposure and the health status of the occupants of a building will determine the health effects on an individual. Heavy metals were detected in the dust in the following ascending order: arsenic (As) ranged from 1.3 ug/g -18.4 ug/g (mean, 4.26 ug/g), lead (Pb) ranged from 28.0 - 872 ug/g (mean 171.66 ug/g), and mercury (Hg) ranged from 0.6 -19.0 ug/g (mean, 2.22 ug/g). The mean concentration of lead in the dust was within the range of Canadian National Classification guidelines on residential contamination (500 ug/g). There was numerous numbers of samples in this study that exceeded these guidelines. The mean concentration of arsenic was within residential soil guidelines (20 ug/g). Mercury was within limits when compared with Global Hg project guidelines of soil/residential (6.6 ug/g), thought some of samples were notably above this mean. The ability of house dust extract to lower the cell viability which was slightly above 80% (prior treatment) to less than 50% (post treatment) in both cells was observed in this study. The findings in this study showed that dust extract are toxic to human cell lines, and cells undergone a degree of apoptosis and necrosis 62% (A549) and 99% (BBM). The cytokines serve an important role in the non-specific defence external against insults. It was observed that A549 cells up-regulated the release of IL-6 and IL-8 pro-inflammatory cytokines and under-regulated the release of other cytokines analysed (IL-4, IL-13, and TNF-a). BBM cells released IL-4, IL-8 and IL-13 within limit of detection. The presence of moulds in these sampled indoor household dusts, which is comparable with findings elsewhere indoors, show that moulds act as an indicator for building conditions such as dampness, which supports mould growth. Individuals, whether they are sensitized or not, may develop allergic reactions towards spores, thus the elevated numbers of spores quantified in this study are of concern. Some of the heavy metals reported in this study were higher or marginally higher than international norms and guidelines. The findings in this study strongly suggest that house dust extract is toxic to human lung cell lines. It must be noted, however, that this study may not reflect all that happens when a human lung is exposed to house dust. The findings of this study could contribute to the development of South African indoor air guidelines. In conclusion further study needed to be undertaken with respect to air pollution disease such as allergic; the reason being this study shown the reduced expression of cytokines that are involved in allergic inflammation.
Natural ventilation, dampness and mouldiness in dwellings in the Waterloo housing development (Durban Metropolitan Area) : a case study of indoor air quality.
(2004) Gansan, Jaisendra.; Ehiri, J. E.; Gqaleni, Nceba.
Dampness can cause the development of moulds in buildings and pose a threat to the quality of the building structure, indoor air quality and health of the occupants. An emerging source of housing related problems are the building materials commonly used in housing construction, which can influence respiratory health. There is concern regarding the quality of the housing stock in the Durban Metropolitan area with regard to dampness and its the potential impact on the health of occupants. To elucidate this issue, a study was conducted to assess natural ventilation, dampness and mouldiness in dwellings of the Waterloo Housing development (Durban Metropolitan Area), between February 2001 and December 2003. A total of 491 randomly selected homes were visually inspected and residents were surveyed by means of a structured questionnaire. Three hundred and eighteen (318) air and surface mould samples were collected in duplicate, totalling 636 samples and analysed in the laboratory. Building characteristics and physical conditions were recorded and noted. Temperature and relative humidity readings were also taken during the survey. After the analysis of the 491 questionnaires, physical conditions of the dwellings were found to be poor and of concern. With the number (1178) and size of habitable rooms in the dwellings; the occupancy of 2414 people with an average of 2.05 persons per room, indicated overcrowding and congestion. About 51% (n=249) of the dwellings surveyed were found to be experiencing dampness (>3m2) and 47% (n=230) had visible surface moulds, primarily on the walls (at least an average of 1m2) . Predominant airborne fungal organism identified included; Aspergillus (23%-indoors, 26outdoors), Cladosporium (47%- indoors, 51%-outdoors), Penicillum (27%-indoors, 26%-outdoors) spp. Natural ventilation was also inadequate in 261 (53%) dwellings, which did not have airbricks. This inadequacy significantly promotes the occurrence of dampness and surface moulds (p < 0.05). With poor ventilation, dampness and mould growth in the dwellings, there was a high number of cases with upper respiratory tract health complaints; like Cough - 25% (n=122), Sinuses - 25% (n=121), flu symptoms 23% (n=llO) lower respiratory infections such as asthma - 27% (n=130), and chest infections - 23% (n=113). Asthma, wheeze, runny nose and allergy to dust were statistically associated with dampness (p < 0.05), mouldiness (p < 0.03) and lack of ventilation (p < 0.01). Buildings separate their occupants from hostile external environments and create a better internal environment for them, therefore dwellings must be constructed in a manner that promotes the health and well being of the occupants. In terms of guiding regulations, there were several omissions and non-compliance with existing local building bye-laws in the construction of houses, leading to adverse implications. Improved workmanship, appropriate material selection and compliance with the relevant guidelines during planning and construction inter alia, are recommended when addressing housing issues, thereby promoting the interest, health and well-being of the users.
Toxicological analysis of South African paraffin.
(2007) Dlamini, Nonhlanhla.; Gqaleni, Nceba.
There is little information available on the relationship between the chemical composition and toxicity of South African paraffin. The aim of this study was therefore to determine an association, if any, between the chemical composition and toxicity of South African paraffin. The objectives were to analyze the chemical composition and potential toxicity of paraffin using an A549 lung cell line. There were two phases to the study. In the first phase of the study the chemical composition of seven (7) paraffin samples was tested at accredited InterTek Testing Services (ITS) according to SABS protocol. In the second phase of the study toxicology studies were conducted using the MTI and Annexin assays to establish the toxicity of the samples. The experiments included dissolving paraffm in a constant volume of ethanol. Results of the chemical analysis of paraffin from local refineries indicated that the major components were aliphatic hydrocarbons (>75%, v/v), olefins (1-8%, v/v), aromatics (1-20%, v/v) and sulphur «0.1%, v/v). Cytotoxicity tests indicated that there were significant (p<0.001) differences in the level of toxicity of the paraffin samples. The chemical composition or formulation was the single most important factor, which determined the degree of toxicity. The toxicity of paraffin dissolved in ethanol was significantly (p<0.001) more toxic when compared to that of undissolved paraffin. Paraffin samples also induced apoptosis and necrosis. It is therefore recommended that the chemical composition of paraffin must be standardized to a consistent less toxic product to ensure the safety of the South African public.
Occupational exposure and genotoxicity among Ethekwini Municipality petrol attendants.
(2013) Makwela, Mpho Hazel.; Naidoo, Rajen.
Background Benzene, a constituent of petrol, is classified as a Group 1 carcinogen. Once benzene enters the human body, its breakdown products, benzene oxide (BO) and 1.4 benzoquinone (BQ), have the ability to interact with DNA and proteins. Hydroquinone (HQ), a metabolite of benzene, has the ability to produce toxicity in the bone marrow once it interacts with phenol. The effects of genotoxicity are seen in a metabolizing gene (CYP2E1), detoxification genes (NQO1 and GSTT1), and in DNA-repair gene (XRCC1). Purpose To determine whether occupational exposure among eThekwini Municipality petrol attendants is associated with DNA damage. Methods This analytic cross sectional study included 151 participants that comprising of 75 high-exposed petrol attendants, 26 low-exposed workers from eight petrol stations within the city of Durban, and 50 office-based controls from University of KwaZulu-Natal. Researcher administered validated questionnaires were used to establish an association between DNA tail length via comet assay and the volume of petrol pumped in the past year, adjusting for various covariates through multivariate modelling. Results The median duration of employment in the petroleum industry was 4.5 years (range: 1-14 years) among the 26 low exposed and 5 years (range: 1-27 years) among 75 high-exposed pet-rol attendants. The median volume of petrol pumped by the 75 petrol attendants was 182 metric tons in the past year (range: 18-573 tons). The median tail lengths were 60.5μm (range: 18-149) for the high exposed, 89.5μm (range: 24-124) for the low exposed and 56 μm (range: 14-80) for the unexposed. Wilcoxin rank test, showed a statistically significant association between job title and tail length among the exposed and unexposed group. Mann Whitney test showed alcohol consumption to have a significant influence on the level of DNA damage. The multi-variate analysis showed a statistically significant association between job category, smoking, alcohol consumption and comet tail length. Conclusion Occupational exposure was associated with an increased comet tail length among the exposed group compared to the unexposed. Cumulative exposure of volume of petrol pumped over one year duration had no significant dose related risk and was not associated with an increase in DNA damage.
Workplace risk factors associated with extra-pulmonary tuberculosis among healthcare workers in eThekwini health district, KwaZulu-Natal.
(2022) Bhengu, Nontuthuzelo May.; Naidoo, Rajen.
Background Tuberculosis (TB) can be categorized as pulmonary tuberculosis (PTB) and extra-pulmonary tuberculosis (EPTB) involving other organs besides the lungs. Healthcare workers (HCWs) are at increased risk of tuberculosis exposure. The average burden among healthcare workers is 2% compared to 0.9% in the general population. EPTB constitutes about 16% of all TB cases. This study aimed to examine occupational, environmental, and demographic risk factors associated with EPTB among healthcare workers. Methods This was a retrospective case referent type study with two control groups (one without tuberculosis and the other with pulmonary tuberculosis) and cases defined as those with EPTB. 282 records of healthcare workers were reviewed from January 2009 to December 2017.The study reviewed available medical records of healthcare workers from various categories and departments, both clinical and non-clinical. in health facilities within eThekwini Health District, Durban, South Africa. Data was analysed using a chi-square test, t- test and multivariet analysis. Results The mean incidence of TB in 2016 was 908/100 000 and for EPTB, was estimated at 87.2/100 000 HCWs in eThekwini Health District. Cases without respiratory protective equipment (RPE) use were more than three-fold suceptible (aOR 3.5 95%CI 1.0 – 11.4) compared to a PTB control. Working in a clinical department increased the odds for developing EPTB almost three-fold when compared to those with PTB (aOR 2.9 95% CI 0.6 – 13.2) than among those with no TB (aOR 1.4 95%CI 0.1– 13.8). As expected, HCWs diagnosed with HIV were almost two-fold likely to be exposed to EPTB when compared to thosed with PTB (aOR: 1.9 95% CI 0.9 – 4.0), however, when comparing EPTB to no TB, HIV positivity had a wide confidence interval (aOR: 23.4 95% CI 8.1 – 67.7) rendering the results indeterminate. Conclusion Occupational risk factors for EPTB are similar to that of pulmonary tuberculosis, however, risk estimates may be greater than those for PTB. Human immunodeficiency virus/ acquired immunodeficiency syndrome (HIV/AIDS) infection increases the odds of exposure to EPTB in HCWs.

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