The primary cause of COPD is long-term exposure to harmful particles or gases that irritate and damage the lungs. The most common cause is tobacco smoking, including secondhand smoke. Other causes include exposure to air pollution, chemical fumes, and dust in the workplace. Genetic factors can also play a role, as individuals with a genetic condition called alpha-1 antitrypsin deficiency are at increased risk of developing COPD. A study published in the American Journal of Respiratory and Critical Care Medicine found that occupational exposures, such as coal mining and welding, significantly contribute to the development of COPD, even in non-smokers.
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