Silicosis, or miner’s phthisis, is a type of occupational lung disease caused by inhaling crystalline silica dust (a common mineral also known as quartz). It is an irreversible, progressive and incurable disease and can cause inflammation and scarring in the form of nodular lesions in the upper lobes of the lungs. At later stages, silicosis is disabling and eventually fatal.
Crystalline silica dust damages lung tissue when inhaled and results in scarring or fibrosis, which reduces lung function. Multiple mining processes can generate crystalline silica dust such as blasting, drilling and the handling and transporting of rock containing quartz.
Patients can be diagnosed with one of three types of silicosis depending on the disease’s severity, onset and progression:
- Simple chronic silicosis is caused by long-term exposure (more than 20 years) to low amounts of silica dust, which can cause areas of swelling in the lungs and chest lymph nodes and cause difficulty breathing.
- Accelerated silicosis is caused by exposure to larger amounts of silica dust over a shorter period of time (5 to 15 years). Swelling in the lungs and associated symptoms occur faster than in simple chronic silicosis.
- Acute silicosis is caused by short-term exposure to high concentrations of silica dust. The lungs can become inflamed and can fill with fluid, which causes severe shortness of breath and low blood oxygen levels.
Silica dust exposure in high concentrations can lead to silicosis within a year, but 10 to 15 years typically pass before symptoms begin to appear in most victims. Medical monitoring and treatment may include: regular x-rays and lung function tests; tests for pulmonary tuberculosis and treatment; immunization against influenza and pneumococcal pneumonia; and antibiotic treatment for lung infection.
Although an entirely preventable disease, silicosis is an epidemic in South Africa.