Not surprisingly, the main cause of Lung Cancer happens to be tobacco smoke from sources such as cigarettes, pipes, and cigars. Though not everyone who smokes will eventually get lung cancer, the harmful substances within smoke can still damage lung cells. Those who inhale 'second-hand' smoke from nearby smokers are just as at risk of Lung Cancer.
There are other risk factors that can contribute to Lung Cancer such as:
Being older than 40 years — most people are older than 65 years when they are diagnosed with Lung Cancer
Have contact with some substances such as radon (a radioactive gas), asbestos, arsenic, chromium, nickel and air pollution
Have family members who have a history of lung cancer