Olfactory tract/bulb metal concentration in Manganese-exposed mineworkers.

BACKGROUND: Manganese (Mn) is an essential micronutrient as well as a well-established neurotoxicant. Occupational and environmental exposures may bypass homeostatic regulation and lead to increased systemic Mn levels. Translocation of ultrafine ambient airborne particles via nasal neuronal pathway to olfactory bulb and tract may be an important pathway by which Mn enters the central nervous system. OBJECTIVE: To measure olfactory tract/bulb tissue metal concentrations in Mn-exposed and non-exposed mineworkers. METHODS: Using inductively coupled plasma-mass spectrometry (ICP-MS), we measured and compared tissue metal concentrations in unilateral olfactory tracts/bulbs of 24 Mn-exposed and 17 non-exposed South African mineworkers. We used linear regression to investigate the association between cumulative Mn exposures and olfactory tract/bulb Mn concentration. RESULTS: The difference in mean olfactory tract/bulb Mn concentrations between Mn-exposed and non-Mn exposed mineworkers was 0.16 µg/g (95% CI -0.11, 0.42); but decreased to 0.09 µg/g (95% CI 0.004, 0.18) after exclusion of one influential observation. Olfactory tract/bulb metal concentration and cumulative Mn exposure suggested there may be a positive association; for each mg Mn/m3-year there was a 0.05 µg/g (95% CI 0.01, 0.08) greater olfactory tract/bulb Mn concentration overall, but -0.003 (95% CI -0.02, 0.02) when excluding the three influential observations. Recency of Mn exposure was not associated with olfactory tract/bulb Mn concentration. CONCLUSIONS: Our findings suggest that Mn-exposed mineworkers might have higher olfactory tract/bulb tissue Mn concentrations than non-Mn exposed mineworkers, and that concentrations might depend more on cumulative dose than recency of exposure.

Exposure of formal and informal nail technicians to organic solvents found in nail products.

Nail technicians are exposed to volatile organic compounds (VOCs) emitted from nail products used in their daily work, which may cause adverse health effects. This study aimed to assess VOC exposure of nail technicians in the South African formal and informal sectors and to provide a task-based exposure assessment of different nail applications. Personal passive sampling was conducted on 10 formal and 10 informal nail technicians located in the northern suburbs of Johannesburg and the Braamfontein area, over 3 days. Real-time measurements were taken to determine task-based peak exposures. The number of clients serviced, working hours, type of nail application, type of ventilation, room volume, and carbon dioxide (CO2) concentrations, were also recorded. There were differences in the nail products used, the types of nail applications performed, the number of clients serviced, and breathing zones VOC concentrations of the formal and informal nail technicians. Some formal nail salons were equipped with mechanical ventilation while the informal nail salons relied on natural ventilation. CO2 concentrations were higher in the informal than the formal nail salons and increased during the course of the working day. Formal nail technicians were exposed to higher total volatile organic compounds (TVOC) concentrations than informal nail technicians, which may be due to the different nail application procedures as well as 'background' emissions from their co-workers-the bystander effect. Acetone was the predominantly detected VOC: the formal nail technicians were exposed to significantly higher TWA (8 h) concentrations [geometric mean (GM) 43.8 ppm, geometric standard deviation (GSD) 2.49] than were the informal nail technicians (GM 9.87 ppm, GSD 5.13). Methyl methacrylate among the informal nail technicians was measured at 89.7% detection frequency, far higher than that among the formal nail technicians (3.4%). This may be attributed to the observed popularity of acrylic nail applications in this sector. Nail applications involving soak-off gave rise to high TVOC peaks at the start of the nail application process. This is the first study to compare organic solvent exposures among formal and informal nail technicians and determine task-based peak exposures. It also brings attention to the often-overlooked informal sector of this industry.

Quantitative Self-Assessment of Exposure to Solvents among Formal and Informal Nail Technicians in Johannesburg, South Africa.

Participatory research, including self-assessment of exposure (SAE), can engage study participants and reduce costs. The objective of this study was to investigate the feasibility and reliability of a SAE regime among nail technicians. The study was nested in a larger study, which included exposure assessment supervised by experts, i.e., controlled assessment of exposure (CAE). In the SAE approach, ten formal and ten informal nail technicians were verbally instructed to use a passive sampler and complete an activity sheet. Each participant conducted measurements on three consecutive days, whereafter the expert collected the passive samplers. Sixty samples were, thus, analyzed for twenty-one volatile organic compounds (VOCs). The reported concentrations of 11 VOCs were converted into total VOC (TVOC) concentrations, adjusted for their respective emission rates (adj TVOC) to allow comparison within and between nail technician categories (formal vs informal), as well as assessment regimes (SAE versus CAE), using the data from the main study. In total, 57 SAE and 58 CAE results were compared, using a linear mixed-effects model. There were variations in individual VOC concentrations, especially for the informal sector participants. The major contributors to the adj TVOC concentrations were acetone and 2-propanol for the formal category, whereas ethyl- and methyl methacrylate contributed most to the informal nail technicians' total exposures. No significant differences in adj TVOC-concentrations were observed between the assessment regimes, but significantly higher exposures were recorded in the formal technicians. The results show that the SAE approach is feasible in the informal service sector and can extend an exposure dataset to enable reliable estimates for scenarios with substantial exposure variations.

Environmental manganese exposure and cognitive control in a South African population.

OBJECTIVE: To characterize the association between environmental (residential air) manganese (Mn) exposure and cognitive performance, focusing on cognitive control, in a Black African population. METHODS: We administered the Go-No-Go, Digit Span, and Matrix Reasoning tests to population-based samples age ≥40 from a high Mn (smelter) exposed community, Meyerton (N = 629), and a demographically comparable low (background levels) non-exposed community, Ethembalethu, (N = 96) in Gauteng province, South Africa. We investigated the associations between community and performance on the cognitive tests, using linear regression. We adjusted a priori for age and sex, and examined the effect of adjustment for education, nonverbal IQ, smoking, and alcohol consumption. We measured airborne PM2.5-Mn to confirm community exposure differences. RESULTS: Compared to Ethembalethu residents, Meyerton residents' test scores were lower (poorer) for all tests: 0.55 (95 % confidence interval [CI] 0.08, 1.03) lower scores for Matrix Reasoning, 0.34 (95 % CI -0.07, 0.75) lower for Digit Span, and 0.15 (95 % CI 0.09, 0.21) lower for Go-No-Go (high frequency discriminability index [probability]). The latter represented the most marked difference in terms of z-scores (0.50, 95 % CI 0.30, 0.71 standard deviations lower). The mean of the z-score of each of the three tests was also lower (0.34, 95 % CI 0.18, 0.50 standard deviations lower). These associations were similar in men and women, but attenuated with adjustment for education. Differences for Matrix Reasoning and Digit Span between the two communities were observed only among those who had lived in Meyerton ≥10 years, whereas for Go-No-Go, differences were also apparent among those who had lived in Meyerton <10 years. Mean PM2.5-Mn at a long-term fixed site in Meyerton was 203 ng/m3 and 10 ng/m3 in Ethembalethu. CONCLUSION: Residence in a community near a high Mn emission source is associated with cognitive dysfunction, including aspects of cognitive control as assessed by the Go-No-Go test.

Effectiveness of a pre-adolescent inter-generational intervention to address HIV and obesity in South Africa, using a pretest-posttest design.

BACKGROUND: Strengthening pre-adolescents knowledge and skills through an age- and culturally-appropriate intervention could prevent health issues later in life. Early interventions could influence the trajectory of future risky behaviour, and may influence health behaviour amongst their parents. The CIrCLE of Life Initiative was developed to address HIV and obesity. We evaluated whether the combined intervention increased knowledge, enhanced skills, and/or promoted healthy behaviour among students (9-12 years old) and their parents. METHODS: The study was conducted from May to December 2018. Trained educators delivered 30-min lessons over ten consecutive weeks with 537 Grade 6 students at five government-run schools, in a district, in South Africa. Schools were purposively selected based on socioeconomic status and urban-rural classification. Students communicated with parents through shared homework activities. A pretest-posttest study design was used, with a 3-month follow up. Both groups completed self-administered paper-based questionnaires. A score of subscales was used in analysis. The pretest and posttest scores were compared for students and parents using a dependent t-test. Differences in outcomes by school quintile were compared using one-way ANOVA. RESULTS: Response rates were high for both students (80.6%) and their parents (83.4%). Statistically significant differences were observed in HIV knowledge in students pretest (mean 8.04, SD 3.10) and posttest scores (mean 10.1, SD 2.70; p < 0.01), and their parents (mean 10.32, SD 2.80 vs 11.0, SD 2.50; p < 0.01). For both students and parents, pre- and post-test obesity awareness mean scores were similar, 1.93, SD 0.92 and 2.78, SD 0.57; p < 0.01, for students; and 2.47, SD 0.82 and 2.81, SD 0.54; p < 0.01, for parents. In the posttest, statistically significant changes were also observed in both groups, enhancing skills in measuring body mass index and pulse rate, and interpreting food labels. Students had a high intention to share gained knowledge with parents who had a high intention to receive it (89.4 and 89.5%, respectively). CONCLUSION: The intervention increased knowledge about HIV and obesity-related awareness, and it enhanced skills in selected outcomes among pre-adolescents and parents. Accurate messages and enhanced communication skills could support inter-generational knowledge transfer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04307966 retrospectively registered on 12 March 2020.

Process evaluation of a pre-adolescent transdisciplinary health intervention for inter-generational outcomes.

BACKGROUND: The CIrCLE of Life Initiative was implemented to 537 grade 6 learners and their parents, in five Government-run South African primary schools. The transdisciplinary intervention was intended to increase knowledge and skills on HIV and obesity. The study aim was to assess and report on the implementation process. METHODS: Data was collected on an adapted Proctor's taxonomy of implementation outcomes, and to assess participants' experiences. Qualitative and quantitative data were collected through educator logbooks, researcher observations, and learner-parent workbooks. RESULTS: Differentiations between the various school contexts were observed. The process evaluation revealed high learner penetration (97.2%), but lower learner and parent exposure (44.3% and 55.5%, respectively). All educators thought that the intervention was a fit for both rural and urban schools, different socio-economic groups, and people of different ethnic and cultural backgrounds. The intervention was perceived to be sustainable, and there were recommendations for adoption into the school curriculum and scale-up if found to be effective. CONCLUSION: The process evaluation facilitated the assessment of the implementation outcomes, described its processes, and acknowledged fundamental characteristics that could justify variability in the intervention impact and outcomes. The value of process evaluations and their benefit to the science of implementation were demonstrated.

Physicochemical Properties of Indoor and Outdoor Particulate Matter 2.5 in Selected Residential Areas near a Ferromanganese Smelter.

Particulate matter (PM) of different sizes and elemental composition is a leading contributor to indoor and outdoor air pollution in residential areas. We sought to investigate similarities between indoor and outdoor PM2.5 in three residential areas near a ferromanganese smelter in Meyerton to apportion the emission source(s). Indoor and outdoor PM2.5 samples were collected concurrently, using GilAir300 plus samplers, at a flow rate of 2.75 L/min. PM2.5 was collected on polycarbonate membrane filters housed in 37 mm cassettes coupled with PM2.5 cyclones. Scanning electron microscopy coupled with energy-dispersive spectroscopy was used to study the morphology, and inductively coupled plasma-mass spectroscopy was used to analyse the elemental composition of the PM2.5. Mean indoor and outdoor PM2.5 mass concentrations were 10.99 and 24.95 µg/m3, respectively. Mean outdoor mass concentration was 2.27-fold higher than the indoor concentration. Indoor samples consisted of irregular and agglomerated particles, ranging from 0.09 to 1.06 µm, whereas outdoor samples consisted of irregular and spherical particles, ranging from 0.10 to 0.70 µm. Indoor and outdoor PM2.5 were dominated by manganese, silicon, and iron, however, outdoor PM2.5 had the highest concentration of all elements. The ferromanganese smelter was identified as the potential main contributing source of PM2.5 of different physicochemical properties.

Depression and anxiety in a manganese-exposed community.

OBJECTIVE: To characterize the association between residential environmental manganese (Mn) exposure and depression and anxiety, given prior associations among occupationally-exposed workers. METHODS: We administered the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI) to 697 study participants in their preferred languages. These participants represented a population-based sample of residents aged ≥40 from two predominantly Black African communities in Gauteng province, South Africa: 605 in Meyerton, adjacent to a large Mn smelter, and 92 in Ethembalethu, a comparable non-exposed community. We investigated the associations between community (Meyerton vs. Ethembalethu) and severity of depression and anxiety, using linear regression, adjusting for age and sex. To document community-level differences in Mn exposure, we measured airborne PM2.5-Mn. RESULTS: Meyerton residents had BDI scores 5.63 points (95 % CI 3.07, 8.20) higher than Ethembalethu residents, with all questions contributing to this significant difference. STAI-state scores were marginally higher in Meyerton than Ethembalethu residents [2.12 (95 % CI -0.17, 4.41)], whereas STAI-trait scores were more similar between the communities [1.26 (95 % CI -0.82, 3.35)]. Mean PM2.5-Mn concentration was 203 ng/m3 at a long-term fixed site in Meyerton and 10 ng/m3 in Ethembalethu. CONCLUSION: Residence near Mn emission sources may be associated with greater depression symptomatology, and possibly current, but not lifetime, anxiety.

A Rapid Motor Task-Based Screening Tool for Parkinsonism in Community-Based Studies.

Background: The prevalence of parkinsonism in developing countries is largely unknown due to difficulty in ascertainment because access to neurologists is often limited. Objective: Develop and validate a parkinsonism screening tool using objective motor task-based tests that can be administered by non-clinicians. Methods: In a cross-sectional population-based sample from South Africa, we evaluated 315 adults, age >40, from an Mn-exposed (smelter) community, using the Unified Parkinson Disease Rating Scale motor subsection 3 (UPDRS3), Purdue grooved pegboard, and kinematic-UPDRS3-based motor tasks. In 275 participants (training dataset), we constructed a linear regression model to predict UPDRS3. We selected motor task summary measures independently associated with UPDRS3 (p < 0.05). We validated the model internally in the remaining 40 participants from the manganese-exposed community (test dataset) using the area under the receiver operating characteristic curve (AUC), and externally in another population-based sample of 90 participants from another South African community with only background levels of environmental Mn exposure. Results: The mean UPDRS3 score in participants from the Mn-exposed community was 9.1 in both the training and test datasets (standard deviation = 6.4 and 6.1, respectively). Together, 57 (18.1%) participants in this community had a UPDRS3 ≥ 15, including three with Parkinson's disease. In the non-exposed community, the mean UPDRS3 was 3.9 (standard deviation = 4.3). Three (3.3%) had a UPDRS3 ≥ 15. Grooved pegboard time and mean velocity for hand rotation and finger tapping tasks were strongly associated with UPDRS3. Using these motor task summary measures and age, the UPDRS3 predictive model performed very well. In the test dataset, AUCs were 0.81 (95% CI 0.68, 0.94) and 0.91 (95% CI 0.81, 1.00) for cut points for neurologist-assessed UPDRS3 ≥ 10 and UPDRS3 ≥ 15, respectively. In the external validation dataset, the AUC was 0.85 (95% CI 0.73, 0.97) for UPDRS3 ≥ 10. AUCs were 0.76-0.82 when excluding age. Conclusion: A predictive model based on a series of objective motor tasks performs very well in assessing severity of parkinsonism in both Mn-exposed and non-exposed population-based cohorts.

Severity of parkinsonism associated with environmental manganese exposure.

BACKGROUND: Exposure to occupational manganese (Mn) is associated with neurotoxic brain injury, manifesting primarily as parkinsonism. The association between environmental Mn exposure and parkinsonism is unclear. To characterize the association between environmental Mn exposure and parkinsonism, we performed population-based sampling of residents older than 40 in Meyerton, South Africa (N = 621) in residential settlements adjacent to a large Mn smelter and in a comparable non-exposed settlement in Ethembalethu, South Africa (N = 95) in 2016-2020. METHODS: A movement disorders specialist examined all participants using the Unified Parkinson Disease Rating Scale motor subsection part 3 (UPDRS3). Participants also completed an accelerometry-based kinematic test and a grooved pegboard test. We compared performance on the UPDRS3, grooved pegboard, and the accelerometry-based kinematic test between the settlements using linear regression, adjusting for covariates. We also measured airborne PM2.5-Mn in the study settlements. RESULTS: Mean PM2.5-Mn concentration at a long-term fixed site in Meyerton was 203 ng/m3 in 2016-2017 - approximately double that measured at two other neighborhoods in Meyerton. The mean Mn concentration in Ethembalethu was ~ 20 times lower than that of the long-term Meyerton site. UPDRS3 scores were 6.6 (CI 5.2, 7.9) points higher in Meyerton than Ethembalethu residents. Mean angular velocity for finger-tapping on the accelerometry-based kinematic test was slower in Meyerton than Ethembalethu residents [dominant hand 74.9 (CI 48.7, 101.2) and non-dominant hand 82.6 (CI 55.2, 110.1) degrees/second slower]. Similarly, Meyerton residents took longer to complete the grooved pegboard, especially for the non-dominant hand (6.9, CI -2.6, 16.3 s longer). CONCLUSIONS: Environmental airborne Mn exposures at levels substantially lower than current occupational exposure thresholds in the United States may be associated with clinical parkinsonism.

Occupational Hearing Loss for Platinum Miners in South Africa: A Case Study of Data Sharing Practices and Ethical Challenges in the Mining Industry.

BACKGROUND: The relevant legislation ensures confidentiality and has paved the way for data handling and sharing. However, the industry remains uncertain regarding big data handling and sharing practices for improved healthcare delivery and medical research. METHODS: A semi-qualitative cross-sectional study was used which entailed analysing miners' personal health records from 2014 to 2018. Data were accessed from the audiometry medical surveillance database (n = 480), the hearing screening database (n = 24,321), and the occupational hygiene database (n = 15,769). Ethical principles were applied to demonstrate big data protection and sharing. RESULTS: Some audiometry screening and occupational hygiene records were incomplete and/or inaccurate (N = 4675). The database containing medical disease and treatment records could not be accessed. Ethical challenges included a lack of clarity regarding permission rights when sharing big data, and no policy governing the divulgence of miners' personal and medical records for research. CONCLUSION: This case study illustrates how research can be effectively, although not maliciously, obstructed by the strict protection of employee medical data. Clearly communicated company policies should be developed for the sharing of workers' records in the mining industry to improve HCPs.

Validation of Parkinson's Disease-Related Questionnaires in South Africa.

BACKGROUND: There are very few epidemiological studies investigating Parkinson's disease (PD) in Africa. The hundreds of local languages and dialects make traditional screening and clinical evaluation tools difficult to use. OBJECTIVE: The objective of the study was to validate two commonly used PD questionnaires in an African population. METHODS: The PD Screening Questionnaire (PDSQ) and Parkinson's Disease Questionnaire (PDQ-39) were modified and translated into Afrikaans, Setswana, and isiZulu and administered to a sample of healthy local residents. We assessed the internal consistencies and cluster characteristics of the questionnaires, using a Cronbach's alpha test and exploratory factor analysis. The questionnaires were then administered to a population-based sample of 416 research participants. We evaluated the correlations between the questionnaires and both a timed motor task and the Unified Parkinson's Disease Rating Scale motor subsection 3 (UPDRS3), using locally weighted scatterplot smoothing (LOWESS) regression analysis and Spearman's rank correlation. RESULTS: Both questionnaires had high overall internal consistency (Cronbach's alpha = 0.86 and 0.95, respectively). The modified PDQ-39 had evidence of five subscales, with Factor 1 explaining 57% and Factor 2 explaining 14%, of the variance in responses. The PDSQ and PDQ-39 scores were correlated with the UPDRS3 score (ρ = 0.35, P < 0.001; and ρ = 0.28, P < 0.001, respectively). CONCLUSION: The translated PDSQ and PDQ-39 questionnaires demonstrated high internal consistency and correlations with clinical severity of parkinsonism and a timed motor task, suggesting that they are valid tools for field-based epidemiological studies.

Estimating miners at risk for occupational noise-induced hearing loss: A review of data from a South African platinum mine.

BACKGROUND: Occupational noise-induced hearing loss (ONIHL) is a complex, but preventable, health problem for South African miners. Meticulously collected data should be made use of to design interventions to address this health issue. OBJECTIVES: A single mine's electronic data were reviewed in a secondary data review to determine, from the records, factors that hearing conservation practitioners deemed useful for identifying 'at risk' miners and to establish factors that would pave the way for the integration of the 2014 hearing conservation programme (HCP) milestones into the mine's current proactive data management system (PDMS). The objectives of this article were to establish how miners with published risk factors associated with ONIHL were managed by the mine's hearing conservation practitioners as part of the HCP; to determine if the mine's hearing conservation practitioners could estimate miners' risk of ONIHL using baseline percentage loss of hearing (PLH) as a hearing conservation measure; and to estimate the contribution of noise exposure to ONIHL risk. METHOD: In a secondary data review design, records in a platinum mine's two electronic data sets were reviewed: the first contained diagnostic audiometry records (N = 1938) and the second comprised a subset of miners diagnosed with ONIHL (n = 73). Data were available for the period 2014-2017 and included demographic, occupational, audiometry and ONIHL diagnosis data. Miners' risk factors associated with ONIHL were identified using the functional risk management structure. A logistic regression model was used for the baseline PLH margins of 0% - 40% (in 5% increments) to estimate the adjusted predictions for miners at risk of developing ONIHL. The contribution of noise exposure as a risk for ONIHL was estimated using a two-way sample proportion test. RESULTS: The mean age of the miners (all male candidates) was 47 ± 8.5 years; more than 80% had worked for longer than 10 years. Valid baseline audiometry records were available for only 34% (n = 669) of the miners. Miners with a 0% baseline PLH had a 20% predicted risk of ONIHL, and a 45% predicted risk if they had a 40% baseline PLH - these employees were referred. The noise exposure risk rankings revealed that 64.9% (n = 1250) of the miners were exposed to 91 dBA - 105 dBA noise exposure levels and that 59 (80.8%) diagnosed with ONIHL were exposed to noise levels of up to 104 dBA. CONCLUSION: These findings indicate significant gaps in the mine's PDMS, requiring attention. Nonetheless, the mine's current data capturing may be used to identify miners at risk of developing ONIHL. The PLH referral cut-off point (≥2.5%) used by the mine's hearing conservation practitioners, when used in conjunction with baseline PLH shifts, was the major factor in early identification of ONIHL in miners exposed to ≥85 dBA noise. An inclusive integrative data management programme that includes the medical surveillance data set of the miners' noise exposure levels, occupations, ages and medical treatments for tuberculosis and human immunodeficiency syndrome is recommended, as these are important risk indicators for developing ONIHL, particularly within the South African context.

Educators' perceptions of organisational readiness for implementation of a pre-adolescent transdisciplinary school health intervention for inter-generational outcomes.

Organisational readiness is an implementation pre-requisite to gain its members' appropriate and committed use of the intervention. Implementation climate and organisational readiness for implementing change were evaluated conjointly to assess organisational readiness for an obesity and HIV health intervention that imparts health information directly to Grade 6 learners, and indirectly to their parents/caregivers in their home environment. The study objectives were to assess the level of organisational readiness at schools and to identify organisational factors (facilitators, barriers and contextual factors). A mixed-methods approach collected data from five public schools in Gauteng, South Africa. Forty-six educators and school management answered a self-administered questionnaire and contributed to a focus group discussion at each school. Mean scores with standard deviations, or median scores with interquartile ranges, were calculated to determine levels of organisational readiness. Qualitative data were transcribed and analysed thematically. The overall implementation climate and organisational readiness for implementing change median scores were acceptable, at 3.6 (IQR 3.2-4.1) and 4.3 (IQR 3.8-4.9), respectively. Results indicated that educators collectively valued the change highly enough to commit to its implementation, and that the motivation for the intervention, associated goals and objectives, the realisation for change, and the benefits thereof were well-comprehended by educators. Thirteen barriers and 13 facilitators were identified. The perceived degree of fit between the significance and values attached to the intervention by educators, and how these would be received by the target group (parents and learners) was also beneficial. Key barriers and facilitators indicated that the intervention needed to be a fit with existing workflows and educational systems. Contextual factors such as intervention appropriateness and acceptability as well as sensitivity to HIV were identified. These findings suggested proactive improvements to further improve the intervention and its implementation strategy.

Manganese exposure, parkinsonian signs, and quality of life in South African mine workers.

BACKGROUND: Manganese (Mn) neurotoxicity is associated with parkinsonism; the associated motor deficits can affect individuals' quality of life (QoL). We investigated associations between Mn exposure, parkinsonian signs, and QoL in Mn mine workers. METHODS: We assessed parkinsonian signs and QoL in 187 black South African Mn mine workers, using the Unified Parkinson Disease Rating Scale motor subsection 3 (UPDRS3) and the Parkinson Disease Questionnaire (PDQ-39), respectively. We estimated cumulative Mn exposure in mg Mn/m3 -years using complete occupational histories and a job-exposure matrix. We investigated the cross-sectional association between cumulative Mn exposure and UPDRS3 score, and the UPDRS3 score and PDQ-39, adjusting for age, using linear regression. RESULTS: Participants' mean age was 41.8 years (range, 21-67 years); 97.3% were male. Estimated mean cumulative Mn exposure at the time of examination was 5.4 mg Mn/m3 -years, with a mean of 14.0 years working in a Mn mine. The mean UPDRS3 score was 10.1 and 25.7% of the workers had a UPDRS3 score greater than or equal to 15. There was a U-shaped dose-response relation between cumulative Mn exposure and UPDRS3 score, with a positive association up to 15 mg Mn/m3 -years of exposure and an inverse association thereafter. Greater UPDRS3 scores were associated with poorer self-reported QoL. CONCLUSION: In this cohort of employed Mn mine workers, parkinsonian signs were common and were associated with both estimated cumulative Mn exposure and poorer QoL.

The association between caesarean section delivery and later life obesity in 21-24 year olds in an Urban South African birth cohort.

BACKGROUND: Obesity is an important public health problem and rates have reached epidemic proportions in many countries. Studies have explored the association between infants delivered by caesarean section and their later life risk of obesity, in many countries outside Africa. As a result of the increasing caesarean section and obesity rates in South Africa, we investigated the association in this country. METHODS: This was a retrospective analysis of data that were collected from a prospective South African birth cohort (Birth to Twenty Plus), established in 1990. A total of 889 young adults aged 21-24 years were included in the analysis. Poisson regression models were fitted to assess the association between mode of delivery and early adulthood obesity. RESULTS: Of the 889 young adults, 106 (11.9%) were obese while 72 (8.1%) were delivered by caesarean section; of which 14 (19.4%) were obese. Caesarean section delivery was significantly associated with obesity in young adults after adjusting for potential confounders like young adults' sex and birth weight, mothers' parity, and education (incidence rate ratio 1.64, 95% CI 1.01-2.68, p = 0.045). CONCLUSION: The association of caesarean section with early adulthood obesity should be interpreted with caution because data on certain key confounding factors such as mothers' pre-pregnancy body mass index and gestational diabetes were not available. Further research from Africa, with larger sample sizes and databases with useful linking of maternal and infant data, should be conducted.

Socio-demographic contributors to health and safety of mine workers in South Africa.

BACKGROUND: Mine workers in South Africa face various health and safety risks, and socioeconomic challenges. OBJECTIVE: This study aimed to assess the associations between socio-demographic factors and health, safety and wellness in the South African mining industry. METHODS: Qualitative and quantitative data were collected from 64 interviews with mine management and labour representatives, 14 focus groups with mine workers, and 875 questionnaires completed by mine workers from three platinum, two gold, one coal, one diamond, and one manganese mine in South Africa. RESULTS: Health challenges included non-communicable diseases, HIV/AIDS, tuberculosis (TB), and respiratory diseases, while safety challenges included worker behaviour, stress and fatigue. Socio-demographic factors associated with disease, sick leave, fatigue, accidents and job satisfaction included age, length of service, race, nationality, education, mining sector, work status, income, housing, domestic crowding, sleep, exercise, alcohol use, and perceived quality of life. CONCLUSION: Socio-demographic factors should be taken into consideration when developing workplace health and safety programmes.

Contributors to Fatigue of Mine Workers in the South African Gold and Platinum Sector.

BACKGROUND: Mine workers in South Africa face challenges relating to poor health and safety, including fatigue risks, and poor socioeconomic and living conditions. Fatigue results in impaired mental and physical performance. The aim of this study was to assess contributors to fatigue of mine workers in South Africa. METHODS: Data collection took place at four gold mines and one platinum mine in South Africa. A total of 21 focus groups were held with individuals in management, union representatives, and mine workers, and 564 questionnaires were completed by mine workers to gather information about fatigue and potential contributors to fatigue at these mines. RESULTS: Qualitatively (through focus groups), fatigue was attributed to extended working hours, harsh working conditions, high workloads, production pressure, and resource constraints, along with aspects relating to demographic and socioeconomic factors, living conditions, lifestyle, health, and wellness. Greater fatigue was significantly associated with younger age, indebtedness, a lack of exercise, poor nutrition, less sleep, increased alcohol use, poor self-reported health, more sick leave, higher stress, and lower job satisfaction. CONCLUSION: The aim of the study was achieved; numerous work-, sociodemographic-, lifestyle-, and wellness-related factors were linked to fatigue in the participating mine workers. Contributors to fatigue should be addressed to improve health, safety, and sustainability in the industry.

Cost and effectiveness of prescribing emollient therapy for atopic eczema in UK primary care in children and adults: a large retrospective analysis of the Clinical Practice Research Datalink.

BACKGROUND: The Clinical Practice Research Datalink (CPRD) was used to evaluate the overall costs to the National Health Service, including healthcare utilisation, of prescribing emollients in UK primary care for dry skin and atopic eczema (DS&E). METHODS: Primary care patients in the UK were identified using the CPRD and their records were interrogated for the 2 years following first diagnosis of DS&E. Data from patients with (n = 45,218) and without emollient prescriptions (n = 9780) were evaluated. Multivariate regression models were used to compare healthcare utilisation and cost in the two matched groups (age, sex, diagnosis). Two sub-analyses of the Emollient group were performed between matched groups receiving (1) a colloidal oatmeal emollient (Aveeno-First) versus non-colloidal oatmeal emollients (Aveeno-Never) and (2) Aveeno prescribed first-line (Aveeno-First) versus prescribed Aveeno later (Aveeno-Subsequently). Logistic regression models calculated the odds of prescription with either potent / very potent topical corticosteroids (TCS) or skin-related antimicrobials. RESULTS: Costs per patient were £125.80 in Emollient (n = 7846) versus £128.13 in Non-Emollient (n = 7846) matched groups (p = 0.08). The Emollient group had fewer visits/patient (2.44 vs. 2.66; p < 0.0001) and lower mean per-visit costs (£104.15 vs. £113.25; p < 0.0001), compared with the Non-Emollient group. Non-Emollient patients had 18% greater odds of being prescribed TCS and 13% greater odds of being prescribed an antimicrobial than Emollient patients. In the Aveeno-First (n = 1943) versus Aveeno-Never (n = 1943) sub-analysis, costs per patient were lower in the Aveeno-First compared with the Aveeno-Never groups (£133.46 vs. £141.11; p = 0.0069). The Aveeno-Never group had ≥21% greater odds of being prescribed TCS or antimicrobial than the Aveeno-First group. In the Aveeno-First (n = 1357) versus Aveeno-Subsequently (n = 1357) sub-analysis, total costs were lower in the Aveeno-First group (£140.35 vs. £206.43; p < 0.001). Patients in the Aveeno-Subsequently group had 91% greater odds of being prescribed TCS and 75% greater odds of being prescribed an antimicrobial than the Aveeno-First group. CONCLUSIONS: Acknowledging limitations from unknown disease severity in the CRPD, the prescription of emollients to treat DS&E was associated with fewer primary care visits, reduced healthcare utilisation and reduced cost. Prescribing emollients, especially those containing colloidal oatmeal, was associated with fewer TCS and antimicrobial prescriptions. TRIAL REGISTRATION: The study is registered at http://isrctn.com/ISRCTN91126037 .

Maternal mortality in Ifakara Health and Demographic Surveillance System: Spatial patterns, trends and risk factors, 2006 - 2010.

INTRODUCTION: Maternal mortality was the subject of the United Nations' fifth Millennium Development Goal which was to reduce the maternal mortality ratio by three quarters from 1990 to 2015. The Sustainable Development Goals (SDGs), target 3.1 requires participating countries to reduce their maternal mortality ratio to less than 70 deaths per 100,000 live births by 2030. Although much research has been conducted, knowing the spatial patterns and risk factors associated with maternal mortality in developing countries helps target scarce resources and intervention programmes to high risk areas for the greatest impact. METHODS: Data were analysed from a longitudinal open cohort of women aged 15 to 49 years, enrolled from 2006 to 2010. An inverse distance weighted method of interpolation was used to assess spatial patterns of maternal mortality. Cox proportional hazards regression analysis was used to identify risk factors associated with maternal mortality. RESULTS: The overall maternal mortality rate for the 36 792 study participants for the five years was 0.79 per 1000 person years. The trend declined from 90.42 in 2006 to 57.42 in 2010. Marked geographical differences were observed in maternal mortality patterns. The main causes of maternal death were eclampsia (23%), haemorrhage (22%) and abortion-related complications (10%). There was a reduced risk of 82% (HR = 0.18, 95% CI:0.05-0.74) and 78% (HR = 0.22, 95% CI:0.05-0.92) for women aged 20-29 and 30-39 years, respectively, compared with those younger than 20 years. While being married had a protective effect of 94% (HR = 0.06, 95% CI: 0.01-0.51) compared with being single, women who were widowed had an increased risk of maternal death of 913% (HR = 9.13, 95% CI: 1.02-81.94). Women who belong to poorer, poor and least poor socioeconomic quintile had 84%, 71% and 72% reduction in risk of maternal mortality respectively compared to those in the poorest category (HR = 0.16, 95% CI: 0.06-0.42; HR = 0.29, 95% CI: 0.12-0.69; HR = 0.28, 95% CI: 0.10-0.80). CONCLUSION: Maternal mortality has declined in rural southern Tanzania since 2006, with geographical differences in patterns of death. Eclampsia, haemorrhage and abortion-related complications are the three leading causes of maternal death in the region, with risk factors being younger than 20 years, being single or widowed, and having a low socioeconomic status.