Every year, about 1,000 miners die from black lung disease in the United States, according to the Centers for Disease Control and Prevention. Black lung disease is caused by long-term exposure to coal, graphite or man-made carbon. Doctors call this preventable condition Coal Worker's Pneumoconiosis, or CWP. The risk of developing the disease depends on the length of exposure over time. Most people who receive the diagnosis of black lung disease are over 50 years old, according to University of Maryland Medical Center.
Simple Form
There are two forms of black lung disease: simple and complex. There may be no symptoms associated with the simple form of black lung, but it may progress into the complex form. When coal dust enters the lungs, the body's defense mechanisms kick into action. The lungs produce inflammation where encased dust, called coal macules, is stored. Simple form of black lung disease means individual coal macules are present in empty spaces in the lungs near the bronchioles, which are the small tubes in the airway. Bronchioles have thin walls, ending in the air sacs called alveoli which look like a cluster of grapes.
Complex Form
The complex form of black lung disease can cause dysfunction of the lungs. Individual coal macules begin to accumulate and form into coal nodules. Patients may experience respiratory symptoms, such as coughing and difficulty breathing.
Fibrosis
The patient may develop fibrosis in the complex form of black lung; this is the development of excess fibrous tissue in the lung. Fibrous tissue decreases lung elasticity which is very important to the function of the lungs.
Emphysema
The patient can develop emphysema when the coal nodules cause the bronchiole walls to weaken. Emphysema is when air flow is restricted while exhaling, according to MayoClinic.com. The elastic fibers that hold the alveoli open collapse, preventing air from escaping. Bronchiole are eventually destroyed and the air sac clusters they served turn into irregular pockets with gaping holes. This decreases the number of viable air sacs, and therefore the lungs cannot inhale as much oxygen.
Progressive Massive Fibrosis
The Merck Manuals Online Medical Library states that 1 to 3 percent of those with simple black lung will develop progressive massive fibrosis, or PMF. These patients experience respiratory difficulties that get worse over time. They may begin coughing up black sputum if the PMFs ruptures, spilling the contents into the airway.
Cavitation
Cavitation describes a condition where dead material leaks out of the coal macules, causing empty cavities, as described by University of Utah Health Sciences Library.
