As a member of the international silicosis elimination programme, the NIOH currently participates in various global and national research projects aimed at eliminating silica-based diseases in South Africa. Projects are currently under way to study the relationship between silica exposure and related diseases with particular emphasis on tuberculosis, to determine early biomarkers for silicosis, and to increase the awareness of silicosis in workers in the mining industry.

Following the link between crocidolite asbestos and malignant mesothelioma made at the NIOH in 1960, the NIOH embarked on many research projects into asbestos and mesothelioma. However, there is still controversy surrounding the ability of chrysotile asbestos to induce mesothelioma; this association has not been described in South Africa to date and may be due to contamination by other types of amphibole asbestos. To clarify this and other uncertainties around the mesotheliomagenicity of asbestos, the health effects of asbestos are currently studied at the NIOH, using a non-human primate model.

The following projects are classified under this focus area:

Silica and Silicosis

• Comparison of X-ray diagnosis of silicosis with autopsy data – On-Going
• Effect of crystalline silica: an investigation of the mechanism leading to increased susceptibility to mycobacterial infection in silica-exposed individuals – On-Going
• Evaluation of the Comet Assay to assess oxidative DNA damage and repair capacity in the peripheral mononuclear cells of systemic sclerosis and systemic lupus erythematosus and silicotic patients–  On-Going
• Exposure to respirable crystalline silica in central South African farm workers – On-Going
• Isolation and identification of fractions from South African herbal remedies with anti-oxidant activities against silica-induced oxidative stress – On-Going
• Silicosis training for mine health and safety representatives – On-Going
• Validation of biomarkers for improved assessment of exposure and early effect from exposure to crystalline silica: (Part 2) – On-Going
• What does silicosis mean to mine managers and supervisors? – On-Going
• Crystalline silica induced inflammation – 2008

Asbestos and Asbestosis

• Experimental inhalation studies of fibres in non-human primates exposed to low dose asbestos fibres – On-Going