Human lungs are susceptible to potentially harmful substances at work in certain occupations and in the environment. The substances can be in the form of dust, gasses, fumes and smoke. Since lung has wide surface area, rich blood flow and thin lining of the air sacs, it is vulnerable to come in contact with substances in the environment.
Black lung disease is one such occupational health hazard resulting from inhaling coal dust. It is a disease that occurs after exposure to coal dust for long duration of time. In this disease the lung turns black and hard instead of normal spongy and pink color, hence the name black lung.In medical literature, black lung disease is considered to be a type of pneumoconiosis, known as coal workers pneumoconiosis (CWP).
Causes Of Black Lung Disease
Black lung disease is more likely in miners who have spent more than 20 years in coal mines. With constant long term inhalation of coal dust, it begins to accumulate in the lungs. CWP can be in simple and complicated form. Miners involved in transportation, loading and storage of coal are prone to lung disease. Workers involved in manufacturing of carbon electrodes are also likely to be exposed to heavy dust load.
The accumulated dust over a period of time blocks the airways called respiratory bronchioles. In at least 2 to 3 percent of cases as there is increase in the deposition of dust, the lesions increase in size and number. This will lead to scarring and destruction of lung tissue. The condition is then referred to as complicated CWP or progressive massive fibrosis.
Signs And Symptoms Of Black Lung Disease
The simple form of black lung disease does not exhibit any symptoms in majority of cases. Simple coal workers pneumoconiosis is easily recognized on chest radiography.However, if the person is suffering from other respiratory ailments, he may have symptoms of cough and breathing difficulty.
In its advanced stage the individual may present with cough, black sputum, and breathlessness on exertion. This affects the quality of life as person is unable to walk long distance due to breathlessness.
Simple coal workers pneumoconiosis may be associated with rheumatoid arthritis. Complicated progressive massive fibrosis leads to strain on the right side of heart. Gradually the heart increases in size eventually leading to right sided heart failure.
Diagnosis And Treatment For Black Lung Disease
Patients past and present occupational history, the intensity and duration of exposure to coal dust, and present symptoms will help the physician to diagnose the possibility of black lung disease. X-ray of chest will reveal small, rounded opacities of uniform size. Pulmonary function test may reveal abnormality in complicated CWP. In blood test there is increased prevalence of antinuclear antibodies.
There is no definite cure once the person is found to be suffering from black lung disease. Hardening and damage that once occurs to the lungs due to inhaled coal dust for a long period of time cannot be reversed. The only treatment is to make an effort to minimize further exposure to coal and graphite dust by the patient. This will help to prevent further deterioration of his health.
Patient has to stop smoking. Smoking does not cause the disease, but it can worsen the symptoms. The condition is treated symptomatically. Broncho-dilators and oxygen therapy may be required to allow easy breathing. Broncho-dilators will help in keeping the airways clear.