Lung cancer develops when cells in the lungs begin to grow uncontrollably, eventually forming tumors that interfere with breathing and oxygen exchange. While smoking remains the number-one trigger, research now shows that about 10% to 20% of all lung cancer cases occur in people with no smoking history whatsoever. That means millions of people may be vulnerable for reasons that have nothing to do with tobacco.
The Role of Air Pollution and Environmental Exposure
One of the strongest culprits identified in recent years is air pollution. In many cities — particularly those with dense traffic or heavy industry — the levels of fine particles known as PM2.5 and PM10 often exceed safe limits. These microscopic pollutants can travel deep into the lungs, causing inflammation and long-term damage to lung tissue. Over time, that irritation can lead to mutations that spark cancerous growths.
