Respiratory Diseases
Asbestosis
Asbestosis is a serious, long-term lung disease caused by inhaling asbestos dust over a prolonged period.
Asbestos is a naturally occurring fibre that was widely used for various industrial purposes, such as insulation and ship-building until the mid 1980s. Since the health effects of asbestos started to become clear, the supply and use of asbestos and asbestos products has been banned for all but a few exceptions by the Asbestos (Prohibition) Regulations.
There are three main types of asbestos - often called white, brown and blue asbestos. The use of blue and brown asbestos (the two most dangerous forms) are banned totally by law and white asbestos is used in the UK only in exceptional circumstances.
People working in industries where asbestosis was used extensively, such as demolition work, plumbing, and at power stations, were likely to have been exposed to breathing in fibres of asbestos, often over a period of years. Changes in the lung occur slowly - asbestosis can take 20 years or more to develop - so ill effects were not instantly traceable to asbestos.
Asbestosis is one of a number of conditions that can be caused by exposure to asbestos. Other related conditions include mesothelioma (a malignant tumour in the lung) and benign pleural thickening (the lining of the lung is thickened and hardened).
At least 3,500 people in Great Britain die each year from mesothelioma and asbestos related lung cancer as a result of past exposure to asbestos.
Symptoms
The main symptoms of asbestosis are:
- increasing breathlessness, especially when exercising.
- coughing.
- chest pain.
- a feeling of tightness in the chest.
Asbestosis may damage the function of the lungs so much that the condition progresses to respiratory (breathing) failure. At this stage the oxygen supply to the body is so poor that the patient is always breathless and often has blue-tinged skin (cyanosis) even when at rest in bed.
Other symptoms that sometimes occur are nail abnormalities and clubbing of the fingers. Clubbing is when the fingers become thicker and broader, and the tip of the nails curve.
Diagnosis
Firstly, your GP will find out about your history of exposure to asbestos, in particular, whether you have been exposed to large quantities, or over a long period of time.
Breathlessness is a key symptom that will help your doctor to diagnose asbestosis. When holding a stethoscope to the chest, your GP may be able to detect a crackling sound as you breathe.
Lung function tests may be carried out to check for:
- scarring (fibrosis) of the lungs.
- a reduction in the amount of air that is breathed in and out.
- how well the lungs work to take in oxygen and get rid of carbon dioxide.
A chest x-ray or CT scan may be taken as part of this investigation. It may also be necessary to carry out a biopsy, where a small sample of tissue from the lung is taken for examination.
Other lung conditions such as lung cancer will need to be ruled out as part of the diagnosis.
Treatment
It is not possible to reverse or cure asbestosis, although if caught early enough the worsening of the condition can usually be slowed or even stopped.
The speed at which the condition progresses depends on several factors, such as how much asbestos has been breathed in, whether the disease has occurred very soon after exposure, whether there are other symptoms such as clubbing, and if the person smokes.
The main treatment used in asbestosis is oxygen therapy, to try to increase the flow of oxygen into the body and counteract the effects of breathlessness.
Corticosteroids or immunosuppressive drugs may be used to try to relieve symptoms. A procedure called thoracentesis, which involves draining fluid from the lungs, may make breathing earlier. Lung transplantation is not extensively used but it has occasionally had success in treating asbestosis.
Stopping smoking can help to slow the progress of the condition and help to reduce the chances of lung cancer. People with asbestosis are particularly vulnerable to chest infections, so they should have the flu and pneumococcal vaccine.
Prevention
It is now illegal to use asbestos in the construction or refurbishment of any buildings. However, this substance was used extensively in the past. As long it remains in good condition it is not a great threat, but if it is disturbed or damaged the fibres will be released. They may then be breathed into the lungs of occupants of the building, especially of people working with the substance, for example drilling holes into walls or removing old insulation. Therefore, precautions should always be taken if the presence of asbestos is suspected.
If you are having asbestos removed from your house or place of work, keep exposure to a minimum. No level of exposure is completely safe, so make sure that people who are not working on the removal do not come into contact with the dust.
Asbestosis can be prevented by effective dust control in the workplace. Recommended measures include forced-draught ventilation, the use of effective masks and total avoidance of smoking.
