The risk of contracting an asbestos related disease increases with cumulative exposure and also with the passing of time since the first exposure to asbestos occurs. Airborne asbestos fibres which are inhaled or swallowed may remain in the body for decades. Before these ingested asbestos fibres ultimately cause injury, a latency period of 40 years or more following first exposure to asbestos can elapse.
Who is at risk?
Any person exposed to asbestos is at risk of developing an asbestos-caused injury or illness. Exposure at work, at home or in the community generally can and does occur. Even exposure to asbestos as a child or when handling clothing or equipment itself exposed to asbestos can cause injury.
Cigarette smoking combined with asbestos exposure greatly increases the risk of the development of lung cancer.
Activities where exposure to asbestos may occur can involve:
These can take 7 years or more to develop in the lung following asbestos exposure. A pleural plaque is an indicator of previous asbestos exposure. It is a thickened patch on the lining or pleura of the lung. Plaques may be present in both lungs and in considerable numbers. Pleural plaques are often discovered by chest x-ray or high resolution CT scanning. Generally, pleural plaques do not impair lung function and therefore require no medical treatment. A large pleural plaque can reduce lung expansion and lead to shortness of breath.
When asbestos fibres lodge in the lungs and cause scarring to lung tissue, symptoms of breathlessness and fatigue can develop leading to a diagnosis of asbestosis. Like pleural plaques, asbestosis is not a cancer but it is a serious industrial disease which can result in significant physical disability. Asbestosis can lead to a painful death as scarring to the lungs can continue to develop despite there being no further asbestos exposure.
In all claims involving the condition of asbestosis, the lung condition called idiopathic pulmonary fibrosis (which is clinically diagnosed as usual interstitial pneumonia) must be excluded. This will require expert respiratory analysis of CT scan results and lung function testing as well as an assessment of the appropriate work history. Asbestosis can develop after a latency period of 10 years or more following the first asbestos exposure.
Inhaling or swallowing asbestos fibres can cause a cancer, called mesothelioma, to the lining of the lung. Mesothelioma can also develop in the stomach, the abdomen (peritoneum) or the bowel. Past exposure to asbestos is the only known cause of mesothelioma. This fast growing cancer can take 20 to 45 years to develop. Mesothelioma of the pleura of the lung may develop in one spot or a number of spots. As the cancer grows it can extend into the chest wall and the ribs and produce fluid in the lining of the lung resulting in breathlessness and a dry cough. Mesothelioma in the abdomen causes pain and swelling as well as urinary and bowel dysfunction. There is no known cure for mesothelioma. Sufferers of mesothelioma rarely survive longer than 18 months after diagnosis.
Swallowing or inhaling asbestos fibres can lead to the development of cancer in the lung tissue. Cigarette smokers and diagnosed sufferers of asbestosis are at greater risk of developing lung cancer. There are different types of lung cancer but all can be caused by asbestos exposure. Lung cancer may take decades to develop. Common symptoms of lung cancer include breathlessness, difficulty swallowing, coughing up sputum and constant chest pain. Chest x-ray and high resolution CT scanning can diagnose lung cancer.