Asbestos-related diseases are caused by inhaling asbestos fibres. There's no cure, but early identification can stop the condition from getting worse.
The effects of asbestosis don't tend to appear for many years, often between 25 and 40 years later.
The main symptom is shortness of breath, initially on exertion but later even at rest. Others include tiredness and a cough.
Asbestos can cause thickening of the pleura, the membrane that lines the outside of the lung. Often this will only be noted when an x-ray is performed for another reason. If the thickening is severe and widespread, it restricts lung function causing shortness of breath.
Asbestos is a naturally occurring fibrous mineral often found in insulation materials around pipes and tanks, in tiles and other building materials. It was used extensively in the 1970s because of its strength and heat resistance.
White, blue and brown asbestos are all potentially dangerous. The blue and brown types, which are most likely to trigger asbestos-related illness, have been banned.
Usually, asbestos shouldn't cause problems. However, if it gets damaged the fine fibres become airborne and can be inhaled.
When these fibres penetrate the lung tissue, they trigger an inflammatory reaction. The body recognises there's a problem and sends defensive white blood cells to engulf and attack the fibres.
The fibres usually resist and destroy these blood cells, promoting further inflammation and irreversible scarring of the lungs, called fibrosis.
There's no known safe level of asbestos exposure. However, it's thought the higher the levels of asbestos and the longer the time someone is exposed to it, the greater their risk of developing problems.
Although there's no cure for asbestosis, it's important to prevent the symptoms becoming worse by avoiding further exposure to asbestos.
Medication can be prescribed to relieve symptoms and improve breathing. Some people with severe problems are given oxygen.