SILICOSIS

What you should know about Silicosis

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.

Silicosis is a dangerous, disabling, non-reversible and sometimes fatal lung disease. It is caused by the inhalation of dust containing respirable crystalline silica. Silica is a major component of sand, rock and mineral ores.

Why is the inhalation of silica dust so dangerous?
Exposure to dust that contains microscopic particles of crystalline silica can cause scar tissue to form in the lungs, which reduces the lungs’ ability to extract oxygen from the air we breathe. Severe fibrosis can lead to death from respiratory insufficiency and heart failure in people with advanced or complicated silicosis. People exposed to silica at work, or those who have silicosis, have a much greater risk of pulmonary tuberculosis. Silicosis with tuberculosis or silico-tuberculosis is an important cause of death in people exposed to silica for long periods.

Where does exposure to silica dust happen?
Silica dust is released during work processes in which rocks, sand or concrete are broken into very small particles. Sand blasting is one of the high-risk activities where silica dust becomes airborne. Dry sweeping or clearing of sand or concrete, or grinding or the cleaning of masonry with pressurised air can generate large dust clouds.

How would a worker know if he/she is at risk of contracting silicosis?
All workers who work in a dusty environment where silica dust is present can potentially get silicosis. Silicosis can develop very fast with silica exposure (Acute Silicosis) or fast (Accelerated Silicosis) or slowly (Chronic Silicosis). It can also be complicated by massive fibrosis or tuberculosis.

Workers are cutting the asphalt on the road.

In which workplaces is it most likely to to be exposed to silica dust?
The following are not the only workplaces but they are the most likely ones with the greatest risk:

  • Any industry where sandblasting is done, or where shot blasting of objects with silica content takes place to remove paint and rust from buildings or metal tanks, or frost glass
  • In mines or quarries where drilling through granite or sandstone occurs
  • In the construction industry where activities such as sandblasting, tunneling, rock drilling, jack-hammering and power tool grinding of surfaces containing silica take place
  • Foundries and molding, shake-out, sand or shot blasting, fettling and grinding
  • Industries making ceramics, bricks, clay and pottery
  • Stone or granite cutting, sawing, chipping, grinding and polishing
  • Jewellery manufacturing
  • Glass manufacturing
  • In the Agricultural Sector where fields and crop waste are burned
  • Shipbuilding
  • Railways
  • Manufacturing of soaps and detergents.


What are the symptoms pointing to the possibility of silicosis?
Silicosis may go undetected for years, even 15 or more years if it is chronic and not complicated. A silica exposed worker with tuberculosis might also have silicosis. As silicosis progresses or becomes complicated (e.g. with tuberculosis) the following symptoms may occur:
– Severe cough
– Shortness of breath
– Fatiqiue
– Loss of appetite
– Fever- Chest pains

How would you know if you have silicosis?
If you know that you are exposed to silica dust, you should visit a clinic, hospital or doctor with experience in occupational diseases. The medical examination should include a good occupational history, chest X-rays and a lung function test to determine whether you have silicosis.

Diagnosis
Patients can be diagnosed with one of three types of silicosis depending on the disease’s severity, onset and progression:
1. 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.
2. 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.
3. 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.

What can you do to prevent silicosis?
The following interventions should be considered to prevent silicosis in the workplace:

Primary prevention
The following interventions may prevent silicosis in the workplace:

  • Ensure that engineering methods and ventilation for removing dust at work isin a good working order
  • Apply measures to reduce silica dust levels
  • Minimise dust exposure by using water sprays to wet surfaces wherever possible and keep surfaces including floors as clean of dust as possible
  • Appropriate respirators should be worn at all times in dusty areas
  • Participate in training programmes on the prevention of silicosis.
Medical examination report and stethoscope on white desktop

Secondary prevention
● Get your employer to arrange a medical examination.

Where to go if you have silicosis, silica related tuberculosis or silica related lung cancer attracted in the workplace?
Contact the nearest Provincial Office of the Department of Labour for advice on how to apply for compensation from the Compensation Fund.

What should you do if you need more information on Silicosis?
Contact your nearest Provincial Office of the Department of Labour or visit the Department’s website at www.labour.gov.za