What are the cause of emphysema?

The primary cause of emphysema is long-term exposure to irritants that damage the lungs and impair their ability to function properly. The most common cause of emphysema is cigarette smoking, which exposes the lungs to harmful chemicals and toxins that can lead to inflammation and damage of the air sacs in the lungs. Other causes of emphysema include exposure to air pollution, secondhand smoke, and occupational exposure to dust, fumes, or chemicals. In rare cases, emphysema can also be caused by a genetic condition called alpha-1 antitrypsin deficiency.