Lung cancer has long been linked to cigarette smoking, but new research highlights a growing trend that challenges this assumption. Increasingly, non-smokers—particularly younger women—are being diagnosed with the disease, and experts point to air pollution as a leading culprit.
A study published in The Lancet Respiratory Medicine analyzed global lung cancer trends. It found that adenocarcinoma, the most common subtype of lung cancer, is now the predominant form worldwide.
Unlike other lung cancer types strongly associated with smoking, adenocarcinoma often develops in people who have never touched a cigarette.
The study, conducted by researchers at the International Agency for Research on Cancer (IARC), suggests that environmental factors—especially air pollution—may be driving this shift.
According to the Centers for Disease Control and Prevention (CDC), adenocarcinoma originates in the cells lining the air sacs of the lungs and accounts for nearly half of lung cancer cases among non-smokers.
Researchers found that this subtype made up more than 45% of lung cancer cases in men and nearly 60% in women globally, with the highest rates reported in East Asia, particularly China.
Experts emphasize that exposure to airborne pollutants, such as particulate matter and industrial emissions, can cause long-term damage to lung tissue and increase the risk of cancer.
Some also point to rising vaping rates and secondhand smoke exposure as contributing factors.
Additionally, genetic predisposition may play a role, though more research is needed to understand its full impact.
Beyond pollution, other environmental hazards have been linked to increased lung cancer risk.
Veterans deployed in the Middle East, for instance, may have been exposed to toxic chemicals from burn pits, which incinerated materials ranging from plastics to medical waste using jet fuel.
Medical professionals note that young veterans are now showing signs of lung cancer potentially linked to these exposures.
Despite declining smoking rates, the rising incidence of lung cancer in non-smokers presents a challenge for prevention and early detection.
Experts suggest that artificial intelligence could help identify early lung cancer patterns before visible nodules develop, though lung CT scans remain the gold standard for diagnosis.
With lung cancer continuing to evolve in its risk factors and patient demographics, ongoing research will be crucial in developing more effective prevention and treatment strategies.