Asbestosis

The Facts

Asbestosis is a harmful lung condition that develops in workers who, over the years, have breathed in large amounts of asbestos dust from industrial materials. When someone inhales the dust, the microscopic asbestos fibers settle in the lungs, where they may cause scars and make breathing increasingly difficult.

One of the unusual things about asbestosis is the long "lag-time" between asbestos exposure and the resulting illness - a year of exposure in youth may not cause symptoms until 30 years later. Once someone develops asbestosis, however, there is no cure. Breathing problems will get steadily worse, and in about 15% of people, severe shortness of breath and respiratory failure develop. For someone who smokes and has had asbestos exposure, there is a greatly increased chance of developing lung cancer. Symptoms may appear within ten years of the initial exposure.

Causes

Asbestosis is what doctors call an occupational lung disease, caused by inhaling harmful particles while at work. Diseases due to chronic inhalation of mineral dusts are called pneumoconiosis. The kind of lung disease or pneumoconiosis that develops depends on the size and kind of particles someone keeps breathing in. Luckily, the body is able to get rid of most inhaled particles. Special cells in the lungs engulf them and make them harmless. But some particles like asbestos cause damage that can't be reversed.

Asbestos is the term for a group of minerals used in many industries. They come in various forms that can be identified by the length of the fibers they're made up of. Medium and longer lengths of asbestos fibers seem to be a greater health hazard than shorter fibers. When inhaled into the lungs, asbestos fibers cause scars (pulmonary fibrosis) and may restrict lung movements (restrictive lung disease). Breathing in asbestos can also cause the two membranes covering your lungs (the pleura) to thicken.

The more you are exposed to asbestos fibers, the greater your risk of developing asbestosis or other asbestos-related conditions. You can be at risk for asbestos exposure if you work as a janitor, welder, electrician, plumber, construction worker, carpenter, boilermaker, insulation installer, shipbuilder, miner, or railway worker, or if you're involved in the manufacturing of textiles. Construction work, demolition, renovation, and jobs that require the cutting, filing, sanding, or scraping of asbestos-containing materials may all put you at a high risk.

Symptoms and Complications

If you experience symptoms of asbestosis, this may well mean that many scars have formed in your lungs. The lungs lose their elasticity, or ability to fill up properly with oxygen; thus the first symptoms are shortness of breath and increased breathlessness when exercising. Progressive worsening in your breathing and other symptoms such as cough and wheeze (more in smokers) may develop. You may display what is known as clubbing of the fingertips (they thicken and enlarge), or develop a blue color under your nails and a bluish tinge around your mouth. Even brief exposure to asbestos at some time in the past will dramatically increase the risk of developing mesothelioma - a rare, fatal cancer of the chest lining and abdomen.

Some research has also shown that asbestos causes an increased risk of developing cancers of the esophagus, stomach, intestines, and rectum. This may be related to the swallowing of asbestos fibers that were inhaled and then coughed up from the lungs. If you are a smoker who has been exposed to asbestos over the long term, your likelihood of developing lung cancer is greatly increased, especially if you smoke more than one pack of cigarettes a day. It appears that there is a "dose-response relationship" between asbestos exposure, smokers, and lung cancer: the greater the exposure when smoking, the higher the risk of cancer.

Making the Diagnosis

If you suffer from a cough and habitual shortness of breath, you should tell a doctor about any possible exposure to asbestos. Your doctor will also probably talk to you about your work history to determine this. Because asbestosis has no symptoms that are completely unique, diagnosis is usually made after considering symptoms alongside a confirmed history of asbestos exposure. Only when there is clear evidence of asbestosis will a doctor assume that asbestos exposure played a role. This is because showing a cause-and-effect relationship to work-related asbestos exposure presents many medical and legal problems, especially if you are a smoker. Chest X-rays will confirm whether the lungs are scarred. Pulmonary (or lung) function tests may reveal that lung function is decreased.

Treatment and Prevention

Asbestosis is preventable, mainly through reducing the amount of asbestos dust in the workplace. As many industries are phasing out the use of asbestos because of its health hazards, the number of people who have asbestosis is now decreasing. In the future, the disease may be eliminated.

If you have asbestosis, you must immediately stop all exposure to asbestos. If you're a smoker, you must also stop smoking in order to prevent serious complications. There are no specific treatments available for asbestosis. General treatments available for the kind of restrictive lung disease it causes include bronchodilator inhalers and exercise programs. Shots against pneumococcal pneumonia and the flu are a good idea if you have asbestosis. Therapy with pure oxygen helps if you have an advanced case of the illness.

If you work in an industry that uses asbestos, you should make sure your employer takes preventive steps to ensure your safety and that of your fellow workers. Many countries have adopted regulations about acceptable limits of asbestos exposure and use mandatory guidelines to carefully monitor types and degrees of exposure. Laws are now in force that set standards for protective clothing and regulate the record keeping of data about any possible exposure. Other areas that need close regulation include the use of respirator equipment when asbestos levels are above a specified level, appropriate labelling of materials that contain asbestos, and air and water safety. Employers must provide mandatory medical examinations at specified intervals for workers who are exposed to asbestos.