Background: Exposure to diesel particulate matter (DPM) is a significant health hazard in the workplace, particularly in underground mining settings where dieselpowered machines are utilised. Decreasing DPM exposure relies widely on the ability of the industry to implement diesel emission control technologies; in particular, the use of diesel particulate filter (DPF) systems.
Objective: We explored the effectiveness of retrofitted DPFs in reducing tailpipe DPM emissions from a fleet of diesel-powered machines, and exposures to workers, in an underground platinum mine in Limpopo province, South Africa.
Methods: Using a size-selective particle monitor (Dekati ELPI+), pre- and post- DPF system engine exhaust emissions from 10 trackless mobile machines (TMMs), fitted with wall-flow actively regenerating sintered metal DPFs, were measured. Using the device's built-in software, each measurement was analysed for particle number concentration, mass concentration, and particle size distribution. Personal DPM samples from 172 workers were analysed using Expostats to assess the effects of TMM DPF retrofitting on ambient elemental carbon (EC) exposures.
Results: DPF systems were effective in reducing DPM emissions. Total particle number and mass concentrations were reduced by an average of 96.8% and 83.7%, respectively. Mean personal exposure to elemental carbon was also significantly reduced after the installation of DPF systems, by 87.2%.
Conclusion: The use of DPFs was effective in reducing tailpipe DPM emissions and personal EC exposures. This technology will greatly benefit the South African mining industry (SAMI) by improving compliance with emission standards and preventing adverse health effects as a result of over-exposure of DPM to employees.

Background: Artisanal and small-scale mining (ASM) is a laborious process often executed with rudimentary low-technology mining equipment. It exposes miners to a myriad of occupational hazards, which may increase health and safety disparities between them and formally employed mine workers.
Objectives: The objectives of the study were to identify workplace hazards and the associated risks; and to assess the effects of mining activities on the health and environment of artisanal diamond miners in Kimberley, Northern Cape province.
Methods:v This was an interdisciplinary observational ethnographic study. A workplace assessment was undertaken at seven sites in Kimberley. Participants were conveniently selected; snowballing was used to recruit additional participants. Field notes were recorded from observations. Interview questions included those about the duration of artisanal mining, and the risks faced in the workplace. Data collection included photographic documentation. An inductive and deductive process was used to analyse the data and thematic analysis was conducted.
Results: The observed occupational hazards included physical (ultraviolet radiation exposure, injuries due to trauma), respiratory (silica dust exposure), biomechanical (heavy lifting, repetitive movement), and psychological (work-related stress, anxiety) hazards. There was a paucity of access to, and use of, personal protective equipment (PPE). Workers improvised ways to protect themselves, e.g. by using cloths as masks. There was no recourse to formal occupational health services and social safety networks.
Conclusion: Occupational health and safety challenges included physical, biomechanical, respiratory, and psychosocial hazards. The mining activities had a detrimental impact on the environment.

Atopic dermatitis, a chronic recurrent inflammatory skin disease, typically occurs in childhood, but also affects 1-3% of adults. Adult-onset atopic dermatitis has been described and accepted as an entity, and does not necessarily conform to the criteria tabled in the various guidelines published in the literature. Workers with occupational dermatitis in Gauteng are referred to the National Institute for Occupational Health. Of those diagnosed with contact dermatitis, many are also deemed to have atopic dermatitis. We present two cases that were initially diagnosed as occupational contact dermatitis but were then shown to have adult-onset atopic dermatitis. In these patients, the condition was chronic, recurrent, and persisted after removal from the workplace. They did not have pre-existing atopic eczema and the eczema seemed to be precipitated by factors in the work environment. The condition forced both patients to stop working. Both were resistant to normal treatment with topical emollients and steroid creams; one was also resistant to immunosuppressive drugs. Newer biological drugs are registered in South Africa for the treatment of atopic dermatitis but are not affordable for the majority of patients. These patients illustrate the problem with adhering strictly to the literature guidelines when diagnosing atopic eczema in day-to-day practice. They also illustrate the possibility of adult-onset atopic eczema in an occupational setting. In both our patients, work factors seemed to precipitate its development, and they were initially diagnosed with occupational contact dermatitis.

The Pathology Division at the National Institute for Occupational Health (NIOH) provides autopsy services for deceased workers who worked in controlled mines or works under the provisions of the South African Occupational Diseases in Mines and Works Act, 1973 (Act No. 78 of 1973). This report describes the ages, commodities, employment durations, and occupational cardio-respiratory diseases in miners whose organs were submitted for autopsies in 2019 and 2020. Data were exported from the PATHAUT database into STATA for analysis. Differences in the proportions of disease (expressed per 1 000) were calculated using the Pearson's chi-square test; significance was set at p ? 0.05. There were 759 and 557 records of deceased miners and ex-miners in 2019 and 2020, respectively. Pulmonary tuberculosis decreased from 192/1 000 in 2019 to 153/1 000 autopsies in 2020, and silicosis decreased from 246/1 000 to 223/1 000. However, neither decrease was significant. There was a significant increase in the rate of asbestosis from 50/1 000 in 2019 to 79/1 000 in 2020. Pulmonary tuberculosis (TB), emphysema, and silicosis were the most frequent diseases, with high rates. There was a non-significant decrease in occupational respiratory disease rates in 2020 from 2019, but these remain higher than the rates seen in the early 1990s. The NIOH continues to conduct autopsy surveillance on miners to support compensation for families, and the development of policy and intervention programmes in the mining industry.