Coal worker’s pneumoconiosis (CWP) is also called black lung disease. It results from breathing in coal dust over a long period. This causes scarring of the lungs and increasing difficulty breathing.

CWP affects approximately 16% of coal workers in the United States, and its prevalence in the country has risen, according to a study from 2018.

CWP is also tending to affect more young miners than it did in the past, The National Institute for Occupational Safety and Health (NIOSH) report. There is no cure for CWP and early detection is key, they also note.

In this article, we look at what CWP is, how it affects the body, and how to manage the condition.

CWP occurs when a person inhales coal dust over a long period, and it typically affects coal miners.

The dust causes scarring of lung tissue, which appears on X-rays as shadows called “opacities.”

CWP is classified as a type of pulmonary fibrosis — scarring of the lungs. It is also one of a group of illnesses called coal mine dust lung disease, or CMDLD.

Other diseases in this group include:

  • silicosis
  • mixed dust pneumoconiosis
  • chronic obstructive pulmonary disease, which includes emphysema and chronic bronchitis

There are two types of CWP:

  • Simple CWP: At this stage of black lung disease, the opacities are relatively small.
  • Complicated CWP: Over time, the areas of scarring can grow large, and another name for this issue is progressive massive fibrosis.

CWP develops when a person breathes in coal dust particles that travel into the small airways of the lungs, called the bronchioles.

The dust also reaches the alveoli, the air sacs in the lungs where oxygen and carbon dioxide in the blood are exchanged.

The dust particles settle in the lungs, triggering an inflammatory response as the body attempts to remove them. This leads to the scarring of lung tissue.


The symptoms of CWP may not develop for years, and they can depend on the severity of the disease.

According to Johns Hopkins Medicine, symptoms of simple CWP may be mild or nonexistent.

The American Lung Association (ALA) note that a person with an early stage of the disease may only notice symptoms after strenuous activity.

Symptoms of CWP may include:

  • a cough
  • shortness of breath
  • tightness in the chest
  • increased phlegm production
  • black mucus

A person with a later stage of the disease may experience these symptoms even while resting.

Treatment for CWP cannot undo damage to the lungs, the ALA point out.

Instead, the focus is on easing symptoms, improving the quality of life, and preventing the disease from worsening.

Treatments may involve:

  • medication to open the airways
  • a pulmonary rehabilitation exercise program
  • supplemental oxygen

Someone with very advanced CWP may be a candidate for a lung transplant.

A doctor may also recommend lifestyle changes, such as:

  • quitting smoking
  • staying active
  • having a healthful diet
  • getting the recommended flu and pneumonia vaccinations

It is important to have medications ready and a plan in place when symptoms flare up. Also, it may help to join a support group, such as the ALA’s Better Breathers Club.

According to NIOSH, the risk of developing CWP seems to be higher for people with certain jobs, including:

  • surface miners, particularly drillers and blasters
  • thin seam and high wall miners
  • operators of continuous mining machines or shuttle cars
  • people working in smaller mines

One 2018 study found that among underground coal miners with 25 or more years of experience, 10% had CWP.

Smoking can also increase the chances of developing the disease.

Since breathing in coal mine dust causes CWP, reducing exposure to the dust can help prevent the condition.

Prevention measures include:

  • wearing a mask
  • washing areas of skin that come into contact with the dust more often
  • removing the dust from clothing
  • washing the face and hands before taking any medications, eating, or drinking
  • not smoking
  • getting regular health check-ups

The Mine Safety and Health Administration has set limits for employers regarding how much coal dust miners can be exposed to at work.

Dust control technology is also available for mines, including:

  • water sprays
  • air curtains
  • air scrubbers, which pull dust from the air

Continuous personal dust monitors are also available for some miners. This device shows and monitors the wearer’s level of exposure.

The Federal Mine Safety and Health Act of 1977 mandates that surveillance programs offer coal miners breathing tests and X-rays at regular intervals.

If a person has symptoms of CWP, they may have the option of transferring to another area of the mine, according to this law.

If a person has symptoms of CWP, the doctor will first ask when the symptoms began and whether the person has a history of smoking.

Next, the doctor will perform or request:

  • a physical exam
  • a detailed work history
  • pulmonary function tests
  • a chest X-ray or CT

CWP can cause further health issues, including:

  • progressive respiratory failure
  • chronic obstructive pulmonary disease (COPD)
  • tuberculosis, which is now rare
  • pleuropulmonary malignancy, a rare type of lung tumor
  • heart failure, due to pressure in the lungs

Also, one 2016 study suggests that pneumoconiosis may increase the risk of a stroke.

Anyone who has a cough or shortness of breath and past or ongoing exposure to coal dust should visit a healthcare provider.

It is especially important to receive care if the person is coughing up black mucus.

Coal miners, including those who are inactive or retired, can receive care for chronic respiratory illnesses at government-supported Black Lung Clinics.

CWP causes scar tissue to form in the lungs, and it results from breathing in coal dust.

Miners and their employers can take steps to prevent this disease from occurring. Also, early detection is critical in slowing its progression.

Anyone who has been exposed to coal dust and who has shortness of breath or a cough should receive medical attention.