Silicosis

Silica is found in some types of stone, rock, sand and clay. People who work with these materials can inhale easily the very fine silica dust into their lungs. Once the fine silica dust is inhaled, your body's immune system attacks it and causes swelling and inflammation in your lungs.

The swelling and inflammation in your lungs can cause scar tissue (fibrosis) to form over time. This makes your lungs stiff and not work properly. 

There are 3 types of silicosis:

• Chronic silicosis – this is the most common type of silicosis. The symptoms of silicosis develop slowly and progressively over decades with prolonged silica exposure. 
• Acute silicosis – the symptoms of silicosis develop quickly from a few weeks to less than 5 years after very high levels of exposure to silica. 
• Accelerated silicosis – the symptoms of silicosis develop more quickly than chronic silicosis, within 1 year, but less than 10 years after exposure to a large amount of silica in a short period of time. Accelerated silicosis is especially common in people who work with engineered stone benchtops. 

The symptoms of silicosis usually develop slowly and progressively over many years. If you are exposed to a large amount of silica dust in a short period of time, eg, in accelerated silicosis or acute silicosis, symptoms can develop more rapidly. 

Common symptoms of silicosis include:

• persistent cough
• persistent shortness of breath
• tiredness, fatigue and reduced exercise tolerance
• loss of appetite and weight loss (late symptoms). 

As these symptoms develop slowly, you may not notice them until after you have stopped working with silica dust. Symptoms can also get worse even if you are no longer working in the industry and exposed to silica dust. 

In more severe cases, the scarring of your lungs can put pressure on your heart and cause heart failure. 

Your GP will ask you questions about your symptoms, including your occupation and how long you have been exposed to silica dust. Your GP will also listen to and examine your lungs. Tests that may be done include:

• chest x-ray
• lung function tests or spirometry
• CT scan of your lungs. 

If you have silicosis, you may be referred to a lung specialist doctor for follow-ups. 

There is no cure for silicosis. Treatment aims to relieve your symptoms and check your progression. If you are still exposed to silica dust, your GP or lung specialist doctor will advise you to stop any further exposure. 

If you have silicosis, your lungs are already damaged. There are self-care measures to protect your lungs from further damage, including:

• stopping smoking
• stopping further exposure to silica dust even if that means you have to stop working (you may be eligible for a benefit)
• having annual flu vaccinations and the pneumococcal vaccination
• staying active at a level you can manage – a physiotherapist can help you with the right exercises for you
• seeing your GP or doctor if you have any signs of chest infection so you can be treated, eg, fever, shortness of breath, chest pain or cough. 

Having enough protection from silica dust is the best way to prevent silicosis. Employers in any industry involved in working with silica need to review their business and complete a risk assessment for silica exposure for their workers. Read more about silica dust in the workplace(external link) guide for employers. 

Generally, things that you can do as an employee if you are exposed to silica dust in your workplace include:

• wearing and using personal protective equipment (PPE) correctly – talk to your employer if you need training on how to use a PPE in a correct way
• not bringing dust-covered work clothes home – leave them at your workplace to be cleaned
• washing your hands before eating, drinking, smoking and leaving work at the end of the day. 

Read more about 8 key things for workers to know – controlling silica dust in the workplace [PDF, 89 KB].

Talk to your GP or Work and Income NZ(external link) to find out options and benefits if you have to stop work. In addition, Worksafe NZ(external link) is a New Zealand-based organisation that provides general information and resources regarding workplace health and safety. You can also make claims in relation to work-related health problems through ACC NZ(external link), with a range of possible benefits and support. 

If you need to talk to someone, talk to your GP to find out counsellors available in your area. Alternatively, you can call 1737(external link) or Lifeline Aotearoa(external link) 0800 543 354 for free counselling.