Effects of Asbestos
At least 3500 people in Great Britain die each year from mesothelioma and asbestos related lung cancer as a result of past exposure to asbestos. Annual numbers of deaths are predicted to go on rising into the next decade.
Analyses of mesothelioma deaths indicate that many deaths are due to heavy asbestos exposures in industries like shipbuilding and railway engineering in the past. If current control measures are not adhered to, asbestos removal workers are now potentially at the highest risk, as are workers involved in the refurbishment, repair or maintenance of buildings - such as plumbers, carpenters and electricians.
It is known that asbestos causes the following diseases:
What is benign asbestos related pleural disease (ARPD)?
ARPD usually begins with an inflammation of the pleura leading to fluid collecting in the space between the lung and the chest wall. This may cause some discomfort, but most usually it causes shortness of breath which may come on over days or weeks. When the pleural fluid eventually goes away, the pleura on the lung may become thickened and compress the lung.
Removal of the fluid is usually indicated and is followed by immediate relief of breathlessness. This is a small procedure done with local anaesthetic and it may need to be repeated if the fluid gathers again. The fluid eventually stops coming back if nothing is done and the lung pleura may begin to thicken. This pleural thickening can be seen on xray of CT scan. Because the thickening of the pleura tends to squeeze the lung, which may cause shortness of breath.
Lung Cancer caused by asbestos
The effects of lung cancer are often greatly increased by cigarette smoking (by about 50%). Cancer of the gastrointestinal tract can also be caused by asbestos. The latency period for cancer is often 15-30 years.
Treatment is decided individually for each particular patient, but some general comments can be made. The treatment for lung cancer in asbestos exposed workers is the same as for anyone with lung cancer. The earlier the diagnosis is made, the better the outcome of treatment.
Early lung cancer can sometimes be cured by surgery. If cancer has spread outside the lung, surgery would not usually be recommended as it would not cure the cancer. One form of lung cancer (small cell lung cancer) is usually treated with chemotherapy (drug treatment) and not surgery because the results are better. Radiotherapy is usually given to improve symptoms due to lung cancer.
Mesothelioma
Mesothelioma is a cancer of the pleura (the outer lining of the lung and chest cavity) and/or the peritoneum (the lining of the abdominal wall). This form of cancer is peculiar because the only known cause is from asbestos exposure. The latency period for mesothelioma is often 15-30 years. Occasionally mesothelioma is not in the chest, but occurs in the abdomen. About one out of ten mesotheliomas is abdominal (or peritoneal).
The abdomen is lined with a similar type of tissue to the pleura, but it is called peritoneum when it is inside the abdominal cavity. The first sign of peritoneal mesothelioma is usually swelling of the abdomen. In most cases peritoneal mesothelioma is associated with higher levels of asbestos exposure than pleural mesothelioma.
Unfortunately there is no cure for mesothelioma. There is research going on in England and overseas looking for new treatments. It is known that radio-therapy and drug treatment are not reliable, but there may be some role for these treatments in occasional patients. There are procedures available to stop the repeated build-up of fluid due to mesothelioma in the pleural space. This reduces discomfort and repeated visits to hospital to remove fluid. Treatment may be the injection of a chemical into the chest cavity (chemical pleurodesis), a small surgical procedure with a viewing instrument (thoracoscopy and pleurodesis), or a conventional surgical operation (thoracotomy and surgical pleurodesis). These procedures are done to make life more comfortable, but they do not offer any prospect of permanent cure.
Asbestosis
Asbestosis is a lung disease first found in naval shipyard workers. As asbestos fibres are inhaled, they may become trapped in the lung tissue. The body tries to dissolve the fibres by producing an acid. This acid, due to the chemical resistance of the fibre, does little to damage the fibre, but may scar the surrounding tissue. Eventually, this scarring may become so severe that the lungs cannot function. The latency period (the time it takes for the disease to become developed) is often 25-40 years.
The scarring process cannot be reversed by any known treatment. Life can be made more comfortable by supportive treatment, such as oxygen supplied at home or portable oxygen systems for outings etc. Respiratory rehabilitation programs may also help to improve general body fitness and performance while assisting breathless people to be more comfortable with their disability.