The shared genetic architecture of suicidal behaviour and psychiatric disorders: A genomic structural equation modelling study.

Background: Suicidal behaviour (SB) refers to behaviours, ranging from non-fatal suicidal behaviour, such as suicidal ideation and attempt, to completed suicide. Despite recent advancements in genomic technology and statistical methods, it is unclear to what extent the spectrum of suicidal behaviour is explained by shared genetic aetiology. Methods: We identified nine genome-wide association statistics of suicidal behaviour (sample sizes, n, ranging from 62,648 to 125,844), ten psychiatric traits [n up to 386,533] and collectively, nine summary datasets of anthropometric, behavioural and socioeconomic-related traits [n ranging from 58,610 to 941,280]. We calculated the genetic correlation among these traits and modelled this using genomic structural equation modelling, identified shared biological processes and pathways between suicidal behaviour and psychiatric disorders and evaluated potential causal associations using Mendelian randomisation. Results: Among populations of European ancestry, we observed strong positive genetic correlations between suicide ideation, attempt and self-harm (rg range, 0.71-1.09) and moderate to strong genetic correlations between suicidal behaviour traits and a range of psychiatric disorders, most notably, major depression disorder (rg = 0.86, p = 1.62 × 10-36). Multivariate analysis revealed a common factor structure for suicidal behaviour traits, major depression, attention deficit hyperactivity disorder (ADHD) and alcohol use disorder. The derived common factor explained 38.7% of the shared variance across the traits. We identified 2,951 genes and 98 sub-network hub genes associated with the common factor, including pathways associated with developmental biology, signal transduction and RNA degradation. We found suggestive evidence for the protective effects of higher household income level on suicide attempt [OR = 0.55 (0.44-0.70), p = 1.29 × 10-5] and while further investigation is needed, a nominal significant effect of smoking on suicide attempt [OR = 1.24 (1.04-1.44), p = 0.026]. Conclusion: Our findings provide evidence of shared aetiology between suicidal behaviour and psychiatric disorders and indicate potential common molecular mechanisms contributing to the overlapping pathophysiology. These findings provide a better understanding of the complex genetic architecture of suicidal behaviour and have implications for the prevention and treatment of suicidal behaviour.

Healthcare Utilization 12 Months Prior to Fatal and Non-fatal Suicidal Behaviour in Cape Town, South Africa.

The purpose of this study was to characterize healthcare use for general care and mental health one year before suicidal behavior among individuals with fatal and non-fatal suicidal behavior (NFSB) in Cape Town, South Africa. We linked electronic health records of 484 participants from a case series of 93 completed suicides on whom forensic autopsies were performed at a mortuary in Cape Town, between August 2014 and January 2016; and 391 patients admitted to hospital following NFSB between June 2014 and March 2015, and between August 2015 and August 2017. Time from last healthcare visit to date of suicidal behavior (fatal or non-fatal) was calculated, and Kaplan Meier curves were used to compare the differences by psychiatric diagnoses and study group. Overall, 64.5% of completed suicides and 65.9% of NFSB patients sought general healthcare in the year before suicidal behavior. Most of these visits occurred at hospital outpatient clinics (40.8%) and primary healthcare facilities (31.3%). The prevalence of preexisting psychiatric diagnoses and the use of mental healthcare services was lower for individuals who completed suicide compared to NFSB patients. Common reasons for a healthcare visit among individuals who completed suicide were chronic disease and assault; and psychiatric illness (depression, bipolar, and/or substance use disorders), chronic disease and HIV among NFSB patients. A large proportion of individuals with fatal and NFSB interacted with the healthcare system before suicidal behavior. These findings suggest opportunities for suicide prevention at primary healthcare facilities, antiretroviral treatment centers and emergency departments.HIGHLIGHTSHealthcare access is common among individuals with fatal and NFSB in the year before suicidal behavior.The prevalence of mental disorder diagnoses is higher among NFSB patients than among individuals who completed suicide.A greater proportion of NFSB patients accessed mental healthcare services compared to individuals who completed suicide.

COVID-19 hospital admissions and mortality among healthcare workers in South Africa, 2020-2021.

Objectives: This study describes the characteristics of admitted HCWs reported to the DATCOV surveillance system, and the factors associated with in-hospital mortality in South African HCWs. Methods: Data from March 5, 2020 to April 30, 2021 were obtained from DATCOV, a national hospital surveillance system monitoring COVID-19 admissions in South Africa. Characteristics of HCWs were compared with those of non-HCWs. Furthermore, a logistic regression model was used to assess factors associated with in-hospital mortality among HCWs. Results: In total, there were 169 678 confirmed COVID-19 admissions, of which 6364 (3.8%) were HCWs. More of these HCW admissions were accounted for in wave 1 (48.6%; n = 3095) than in wave 2 (32.0%; n = 2036). Admitted HCWs were less likely to be male (28.2%; n = 1791) (aOR 0.3; 95% CI 0.3-0.4), in the 50-59 age group (33.1%; n = 2103) (aOR 1.4; 95% CI 1.1-1.8), or accessing the private health sector (63.3%; n = 4030) (aOR 1.3; 95% CI 1.1-1.5). Age, comorbidities, race, wave, province, and sector were significant risk factors for COVID-19-related mortality. Conclusion: The trends in cases showed a decline in HCW admissions in wave 2 compared with wave 1. Acquired SARS-COV-2 immunity from prior infection may have been a reason for reduced admissions and mortality of HCWs despite the more transmissible and more severe beta variant in wave 2.

Risk factors for problematic alcohol use among male waste pickers and caddies in Johannesburg, South Africa: a cross-sectional study.

Informal workers may be prone to problematic substance use due to many factors, including adverse working conditions and low income. The aim of this secondary analysis was to investigate problematic alcohol use risk factors among male informal workers in Johannesburg, South Africa. Alcohol use among the two groups of informal workers in the analysis y golf caddies and waste pickers was measured using the World Health Organization (WHO) Alcohol Use Disorder Identification Test (AUDIT) tool. The WHO self-reporting questionnaire (SRQ) for common mental health disorders (CMD) was used to assess mental health. A multivariate logistic regression model was used to explore the predictors of problematic drinking in informal workers. The study consisted of 514 participants, of which 48.4% were golf caddies and 51.6%, waste pickers. Most participants were younger than 40 years (50.9%). Over half of the participants (54.7%) were alcohol consumers and 74.1% were smokers. Over 60% of the participants who were alcohol consumers had a probable drinking problem. Unstratified regression results showed that common mental distress (aOR = 1.06; 95%CI: 1.01-1.09), age: 30-40 years (aOR = 2.17; 95%CI: 1.18-3.97), smoking (aOR = 2.25; 95%CI: 1.34-3.79), and other water sources (aOR = 0.2; 95%CI: 0.04-0.99) were associated with a probable alcohol problem. Waste pickers (aOR = 0.33; 95%CI: 0.20-0.70) were less likely to be problematic drinkers compared to golf caddies. Problematic drinking in this study was common in both caddies and waste pickers along with smoking. Problematic alcohol use was associated with caddying, mental distress, age, and smoking. Measures such as providing counseling services to informal workers and improvement of working conditions may help change the behaviors of these vulnerable groups.

Men and women waste pickers on landfills in Johannesburg, South Africa: divergence in health, and socioeconomic status.

OBJECTIVE: To investigate gender differences in health in informal waste pickers affected by poverty and multiple environmental and work hazards. METHODS: A cross-sectional descriptive study was conducted at two major landfill sites in a large city. Information on health, work hazards and health care access as well as blood pressure, blood glucose, cholesterol and BMI were measured. RESULTS: A total of 361 waste pickers participated in the survey. The women interviewed earned on average 22% less per month than the men waste pickers. The women presented with worse chronic health outcomes (OR 2.69 95% CI 1.51-4.78) and signs of chronic disease (OR 1.73 95% CI 1.02-2.96) compared to men despite showing greater health-seeking behaviours. CONCLUSION: Women waste pickers suffer worse health outcomes, such as lifestyle diseases and HIV. Further research is needed to identify the factors involved. Responsive programs supporting health care, improved working conditions and income for waste pickers may also improve their health.

Organophosphate pesticide exposure as a risk factor for attempted suicide in Cape Town, South Africa: A case-control study.

Pesticides are a commonly used agent for suicide in many Low- and Middle-Income countries (LMICs). However, accumulating evidence suggests that exposure to organophosphate (OP) pesticide may also increase the risk of suicide. We conducted a hospital-based case-control study to investigate whether prior household, garden or occupational OP exposure were associated with attempted suicide using conditional logistic regression modeling. Participants who attempted suicide with any means and were admitted to two Western Cape Province hospitals in South Africa were compared to a sample of controls matched by age, sex and time of admission with unrelated conditions, between August 2015 and August 2017. The means of attempted suicide was not recorded. OP exposure was determined by dialkyl phosphate (DAP) metabolites detected in hair and by environmental and occupational history. Approximately 85% of participants reported using pesticides in the home or garden and 15% of participants reported current or past occupational exposure while working on a farm. Attempted suicide was not associated with reported home or garden OP use (Odds ratio [OR] = 0.59, 95%CI 0.33-1.04), hair DAP metabolites (OR = 1.00, 95%CI 0.98-1.02) or current or past agricultural work (OR = 1.08, 95%CI 0.62-1.87), but was associated with hazardous drinking and unemployment with no household income. We found no evidence that attempted suicide was associated with environmental or occupational pesticide use in an urban South African population attending an emergency center.

Health care access of informal waste recyclers in Johannesburg, South Africa.

INTRODUCTION: Informal waste recyclers contribute significantly to waste removal in South Africa. Waste recyclers face health hazards which are associated with handling and disposal of waste, a lack of personal protective wear and inaccessibility to occupational health care services. Consequently, accessing health care within the public health care sector is important for health outcomes in this population. This study assesses health care access of informal waste recyclers in South Africa to establish baseline information for health planning for potential inclusion of informal waste recyclers into occupational health services. METHODS: A cross-sectional study of informal waste recyclers in two landfill sites in Johannesburg was conducted from March 2018. A standardized structured questionnaire was used to collect information on sociodemographic details, health care utilization, barriers to access and acceptability and affordability of health care. Factors associated with health care utilization were assessed using logistic regression. RESULTS: A total of 363 informal waste recyclers were included in the study. Less than half of informal waste recyclers (41.0%) used health care facilities in the last 12 months. Those who accessed services chose to use facilities close to where they live (87.0%). Barriers to accessing health care services included long waiting periods (36.6%), being unable to take time off work (26.3%) and transport problems (13%). In the univariate analysis, factors such as gender and being treated well at the clinic and location of the health care facility were associated with health care utilization (OR: 1.97, p = 0.05, OR: 1.94, p = 0.02, OR: 0.65, p = 0.04 respectively). CONCLUSION: Informal waste recyclers face numerous challenges to accessing health care. Specific to their informal trade, barriers to health care utilization are related to financial repercussions due to the informal nature of their work.

Illness, Self-Rated Health and Access to Medical Care among Waste Pickers in Landfill Sites in Johannesburg, South Africa.

Waste pickers are exposed to various environmental health hazards, and self-rated health (SRH) could influence their medical care access. This study investigated the association between illness, clinic visits and SRH, and assessed if SRH can increase clinic visits. A cross-sectional study was conducted. SRH was defined as "very good", "good", "fair", and "poor". The illnesses were mental health, infectious, and chronic diseases. Medical care access included clinic visits in the previous 12 months. An ordinal logistic regression model was fitted to assess the association. There were 361 participants, 265 (73.41%) were males. Median age was 31 years, (interquartile range (IQR): 27-39). SRH: poor (29.89%), fair (15.92%), good (43.30%) very good (10.89%). Ever smoked (adjusted odds ratio (AOR): 1.72; 95% confidence interval (CI): 1.11-2.66), mental health (AOR: 1.87; 95% CI: 1.22-2.84), chronic (AOR: 2.34; 95% CI:1.47-3.68) and infectious (AOR: 2.07; 95% CI: 1.77-3.63) diseases were significantly associated with increased odds of reporting poor health. Clinic visit was not associated with SRH. From 99 (31%) individuals who rated their health as poor and ill, 40% visited a clinic (p = 0.0606). Acute and chronic illnesses were associated with poor SRH but this did not increase clinic visits. Provision of mobile clinic services at the landfill sites could increase access to medical care.

Respiratory Health in a Community Living in Close Proximity to Gold Mine Waste Dumps, Johannesburg, South Africa.

The effects on respiratory health in populations living close to silica-rich gold mine dumps are unknown. This pilot study related respiratory health and exposure to mine dump dust using two measures of exposure: exposure group, based on distance lived from the mine dump-high (n = 93) (home <500 m from a mine dump), moderate (n = 133) (500-1.5 km), and low (n = 84) (>15 km, control group); and cumulative exposure index (CEI) derived from exposure group and number of years of residence in each exposure group. Participants were interviewed about respiratory symptoms and had chest X-rays and spirometry. We adjusted for key respiratory confounders. No subject had radiological features of silicosis. The high relative to low exposure group had significantly elevated adjusted odds ratios (aORs) for upper respiratory symptoms (aOR: 2.76, 95% CI: 1.28-5.97), chest wheezing (aOR: 3.78; 95% CI: 1.60-8.96), and spirometry-diagnosed chronic obstructive pulmonary disease (COPD) (aOR: 8.17; 95%CI: 1.01-65.85). These findings were similar for the high relative to medium exposure group, but no significant associations were found for the medium versus low exposure group. Chronic bronchitis and tuberculosis risks did not differ significantly among groups. CEI and exposure group produced similar results. In conclusion, residents residing <500 m from mine dumps had elevated adverse respiratory health effects.

Excess Mortality Due to External Causes in Women in the South African Mining Industry: 2013-2015.

Mining is a recognized high-risk industry with a relatively high occurrence of occupational injuries and disease. In this study, we looked at the differences in mortality between male and female miners in South Africa. Data from Statistics South Africa regarding occupation and cause of death in the combined years 2013-2015 were analyzed. Proportional mortality ratios (PMRs) were calculated to investigate excess mortality due to external causes of death by sex in miners and in manufacturing laborers. Results: Women miners died at a significantly younger age on average (44 years) than all women (60 years), women manufacturers (53 years), and male miners (55 yrs). There was a significantly increased proportion of deaths due to external causes in women miners (12.4%) compared to all women (4.8%) and women manufacturers (4.6%). Significantly increased PMRs were seen in car occupant accidents (467, 95% confidence interval (CI) 151-1447), firearm discharge (464, 95% CI 220-974), and contact with blunt objects (2220 95% CI 833-5915). Conclusion: This descriptive study showed excess deaths in women miners due to external causes. Road accidents, firearm discharge, and contact with blunt objects PMRs were significantly increased. Further research is required to confirm the underlying reasons for external causes of death and to develop recommendations to protect women miners.

Trends in Suicide Mortality in South Africa, 1997 to 2016.

Suicide rates worldwide are declining; however, less is known about the patterns and trends in mortality from suicide in sub-Saharan Africa. This study evaluates trends in suicide rates and years of potential life lost from death registration data in South Africa from 1997 to 2016. Suicide (X60-X84 and Y87) was coded using the 10th Revision of the International Classification of Diseases (ICD-10). Changes in mortality rate trends were analysed using joinpoint regression analysis. The 20-year study examines 8573 suicides in South Africa, comprising 0.1% of all deaths involving persons 15 years and older. Rates of suicide per 100,000 population were 2.07 in men and 0.49 in women. Joinpoint regression analyses showed that, while the overall mortality rate for male suicides remained stable, mortality rates due to hanging and poisoning increased by 3.9% and 3.5% per year, respectively. Female suicide mortality rates increased by 12.6% from 1997 to 2004 before stabilising; while rates due to hanging increased by 3.0% per year. The average annual YPLL due to suicide was 9559 in men and 2612 in women. The results show that suicide contributes substantially to premature death and demonstrates the need for targeted interventions, especially among young men in South Africa.

Prevalence of Respiratory Health Symptoms among Landfill Waste Recyclers in the City of Johannesburg, South Africa.

In developing countries, waste sorting and recycling have become a source of income for poorer communities. However, it can potentially pose significant health risks. This study aimed to determine the prevalence of acute respiratory symptoms and associated risk factors for respiratory health outcomes among waste recyclers. A cross-sectional study was conducted among 361 waste recyclers at two randomly selected landfill sites in Johannesburg. Convenience sampling was used to sample the waste recyclers. The prevalence of respiratory symptoms in the population was 58.5%. A persistent cough was the most common symptom reported (46.8%), followed by breathlessness (19.6%) and rapid breathing (15.8%). Approximately 66.4% of waste recyclers reported exposure to chemicals and 96.6% reported exposure to airborne dust. A multivariable logistic regression analysis showed that exposure to waste containing chemical residues (OR 1.80, 95% CI 1.01-3.22 p = 0.044) increased the odds of respiratory symptoms. There was a significant difference in respiratory symptoms in landfill sites 1 and 2 (OR 2.77, 95% CI 1.03-7.42 p = 0.042). Occupational health and safety awareness is important to minimize hazards faced by informal workers. In addition, providing waste recyclers with the correct protective clothing, such as respiratory masks, and training on basic hygiene practices, could reduce the risks associated with waste sorting.

Common Mental Health Disorders among Informal Waste Pickers in Johannesburg, South Africa 2018-A Cross-Sectional Study.

Waste-picking is an income-generating opportunity for individuals living in poverty. Waste picking is associated with a range of risk factors for common mental disorders (CMD). This study aimed to determine the prevalence and factors associated with CMD among waste pickers in Johannesburg. A cross-sectional study analyzed secondary data for 365 waste pickers. A validated Self-Reporting Questionnaire (SRQ-20) was used to assess CMD. Multivariable logistic regression was fitted to identify factors associated with CMD. The overall prevalence of CMD among waste pickers was 37.3%. The odds of having CMD were 2.5 and 3.2 higher in females and cigarette smokers, respectively (p = 0.019 and p = 0.003). Life enjoyment (Adjusted odds ratio [aOR] 0.54, p = 0.02) and a good quality of life (aOR 0.34, p ≤ 0.001) were associated with lower odds of CMD. The high prevalence of CMD among waste pickers was significantly associated with cigarette smoking, being female, not enjoying life, and a poor quality of life. Mental health awareness of CMD will assist with the prevention, early detection, and comprehensive management of CMD among waste pickers.

Usefulness of occupation and industry information in mortality data in South Africa from 2006 to 2015.

BACKGROUND: There is no population based occupational health surveillance system in South Africa, thus mortality data may be a cost effective means of monitoring trends and possible associations with occupation. The aim of this study was to use deaths due to pneumoconiosis (a known occupational disease) to determine if the South African mortality data are a valid data source for occupational health surveillance in South Africa. METHODS: Proportions of complete occupation and industry information for the years 2006-2015 were calculated for working age and retired adults. Deaths due to pneumoconiosis were identified in the data set and mortality odds ratios calculated for specific occupations and industry in reference to those who reported being unemployed using logistic regression. RESULTS: Only 16.1% of death notifications provided a usual occupation despite 43.1% of the population being employed in the year. The MORs for occupation provided significant increased odds of pneumoconiosis for miners (9.04), those involved in manufacturing (4.77), engineers and machinery mechanics (6.85). Along with these jobs the Mining (9.8), Manufacture (2.2) and Maintenance and repair industries (6.0) have significantly increased odds of pneumoconiosis deaths. The data can be said to provide a useful source of occupational disease information for surveillance where active surveillance systems do not exist. CONCLUSION: The findings indicate valid associations were found between occupational disease and expected jobs and industry. The most useful data are from 2013 onwards due to more detailed coding of occupation and industry.

Environmental Silica Dust Exposure and Pulmonary Tuberculosis in Johannesburg, South Africa.

BACKGROUND: Occupational crystalline silica dust exposure is associated with an elevated risk of pulmonary tuberculosis (PTB). However, there is less evidence for an association with environmental silica dust exposure. METHODS: A cross-sectional study of 310 participants was conducted in an exposed community living within 2 km of gold mine tailings and an unexposed population residing more than 10 km from the nearest gold mine tailing. Chest radiographs (n = 178) were read for PTB, past or current, by three readers. RESULTS: Past or current PTB was radiologically identified in 14.4% (95%CI 9.2-21.8) in the exposed and 7.5% (95%CI 2.8-18.7) in the unexposed groups. Multivariate logistic regression models suggested that PTB prevalence was independently associated with exposure to second-hand smoke (OR = 8.13, 95%CI 1.16-57.22), a lower body mass index (OR = 0.88, 95%CI 0.80-0.98), previous diagnosis and treatment of PTB (OR = 8.98, 95%CI 1.98-40.34), and exposure to dust in the workplace from sand, construction, and/or mining industries (OR = 10.2, 95%CI 2.10-50.11). CONCLUSION: We found no association between PTB and environmental exposure to gold mine tailing dust. However, workplace silica dust exposure is a significant risk factor for PTB in South Africa, and PTB patients of working age should be screened for silica exposure.

Tuberculosis Mortality by Occupation in South Africa, 2011⁻2015.

Work-related tuberculosis (TB) remains a public health concern in low- and middle-income countries. The use of vital registration data for monitoring TB deaths by occupation has been unexplored in South Africa. Using underlying cause of death and occupation data for 2011 to 2015 from Statistics South Africa, age-standardised mortality rates (ASMRs) were calculated for all persons of working age (15 to 64 years) by the direct method using the World Health Organization (WHO) standard population. Multivariate logistic regression analysis was performed to calculate mortality odds ratios (MORs) for occupation groups, adjusting for age, sex, year of death, province of death, and smoking status. Of the 221,058 deaths recorded with occupation data, 13% were due to TB. ASMR for TB mortality decreased from 165.9 to 88.8 per 100,000 population from 2011 to 2015. An increased risk of death by TB was observed among elementary occupations: agricultural labourers (MORadj = 3.58, 95% Confidence Interval (CI) 2.96⁻4.32), cleaners (MORadj = 3.44, 95% CI 2.91⁻4.09), and refuse workers (MORadj = 3.41, 95% CI 2.88⁻4.03); among workers exposed to silica dust (MORadj = 3.37, 95% CI 2.83⁻4.02); and among skilled agricultural workers (MORadj = 3.31, 95% CI 2.65⁻4.19). High-risk TB occupations can be identified from mortality data. Therefore, TB prevention and treatment policies should be prioritised in these occupations.

Concentrations of arsenic and lead in residential garden soil from four Johannesburg neighborhoods.

The 2017 Lancet Commission on Pollution and Health identified soil as an important, daily route of public exposure to a variety of pollutants. Lead and arsenic are two potential soil contaminants associated with serious health effects including reductions in intelligence, behavioral effects and aggressive or violent behavior (lead), as well as skin changes, cancer of the skin, bladder, liver and lungs and developmental delays (arsenic). In this study soil samples were collected, using US EPA methods, from gardens in four Johannesburg neighborhoods, and analyzed for lead and arsenic content using a portable X-ray fluorescence spectrometer. The results showed widely varied concentrations of arsenic and lead in soil collected across the four neighborhoods. Concentrations of lead (range: 0.1-2141.0 mg/kg; mean: 241.7 mg/kg (SD 282.8); median 158.1 mg/kg) exceeding local and international reference levels were found in an inner city suburb, while raised arsenic concentrations (range: 0.1-65.3 mg/kg; mean: 18.3 mg/kg (SD 11.7); median: 19.1) were found in the gardens of a suburb located very close to a mine tailings facility. This study confirms the potential for high levels of exposure to toxic metals in residential gardens in an urban African setting. There is a pressing need for scaled up attention to the public health implications of exposure to soil pollution in developing countries.

Distribution of cancer mortality rates by province in South Africa.

INTRODUCTION: Cancer mortality rates are expected to increase in developing countries. Cancer mortality rates by province remain largely unreported in South Africa. This study described the 2014 age standardised cancer mortality rates by province in South Africa, to provide insight for strategic interventions and advocacy. METHODS: 2014 deaths data were retrieved from Statistics South Africa. Deaths from cancer were extracted using 10th International Classification of Diseases (ICD) codes for cancer (C00-C97). Adjusted 2013 mid-year population estimates were used as a standard population. All rates were calculated per 100 000 individuals. RESULTS: Nearly 38 000 (8%) of the total deaths in South Africa in 2014 were attributed to cancer. Western Cape Province had the highest age standardised cancer mortality rate in South Africa (118, 95% CI: 115-121 deaths per 100 000 individuals), followed by the Northern Cape (113, 95% CI: 107-119 per 100 000 individuals), with the lowest rate in Limpopo Province (47, 95% CI: 45-49 per 100 000). The age standardised cancer mortality rate for men (71, 95% CI: 70-72 per 100 000 individuals) was similar to women (69, 95% CI: 68-70 per 100 000). Lung cancer was a major driver of cancer death in men (13, 95% CI: 12.6-13.4 per 100 000). In women, cervical cancer was the leading cause of cancer death (13, 95% CI: 12.6-13.4 per 100 000 individuals). CONCLUSION: There is a need to further investigate the factors related to the differences in cancer mortality by province in South Africa. Raising awareness of risk factors and screening for cancer in the population along with improved access and quality of health care are also important.

Prenatal Exposure to Cadmium, Placental Permeability and Birth Outcomes in Coastal Populations of South Africa.

BACKGROUND: The impact of prenatal exposure to cadmium (Cd) on birth outcomes is an area of concern. This study aimed to assess an impact of prenatal Cd exposure on birth outcomes in distinct coastal populations of South Africa. METHODS: Cadmium was measured in maternal blood (CdB) (n = 641), cord blood and in maternal urine (n = 317). This investigation assessed the associations between CdB (non-transformed) and birth outcomes across the 25th, 50th, and 75th percentile for birth weight, birth length and head circumference, to test for a linear trend. Associations between natural log-transformed maternal CdB, size at birth and other factors were further evaluated using linear mixed-effects modelling with random intercepts. RESULTS: The average gestational age in the total sample was 38 weeks; 47% of neonates were female, average birth weight was 3065 g and 11% were of low birth weight (< 2500 g). The geometric mean (GM) of the maternal CdB level was 0.25 µg/L (n = 641; 95% CI, 0.23-0.27). The cord blood Cd level was 0.27 µg/L (n = 317; 95% CI, 0.26-0.29) and urine (creatinine-corrected) Cd level was 0.27 µg/L (n = 318; 95% CI, 0.24-0.29). The CdB cord:maternal ratio in the sub-cohort was 1, suggesting that the placenta offers no protective mechanism to the foetus. An inverse association was found between CdB and the lower birth weight percentile in female neonates only (ß = - 0.13, p = 0.047). Mothers who reported eating vine vegetables daily had lower levels of CdB (ß = - 0.55, p = 0.025). Maternal smoking was associated with an elevation in natural log-transformed CdB levels in both male and female cohorts. DISCUSSION: Significant inverse associations between prenatal Cd exposure and birth anthropometry were found in female neonates but not in male neonates, suggesting potential sex differences in the toxico-kinetics and toxico-dynamics of Cd.

The extent, nature and environmental health implications of cottage industries in Johannesburg, South Africa.

Cottage industries comprise a sub-group of informal sector income generation activities which are conducted in the home environment and organized around families or households. Cottage industry workers may be at risk of exposure to harmful substances associated with their work, and given the lack of separation of cottage industry activities from living spaces, their families and neighbors may similarly be at risk of exposure. This study was undertaken to determine the extent and nature of cottage industries in five neighborhoods in Johannesburg (South Africa) A cross-sectional survey was conducted across five communities in Johannesburg in 2012. Data on metal-related cottage industry activities were collected through the administration of a pre-structured questionnaire. Metal-related cottage industry activities were defined as car repairs, spray painting, scrap metal recycling, electrical appliance repairs, welding, hairdressing and metal jewelry making. One fifth of the households interviewed were operating one or more cottage industries associated with the use of toxic substances. Therefore, the potential exists for associated ill health effects in a considerable proportion of the population. Further research is needed to fully assess exposure to the harmful aspects of cottage industry, as are scaled up campaigns to increase awareness of the risks and correct handling of toxic substances.