Smoking is the leading environmental cause of lung cancer and believed to be responsible for around 80 percent of cases. Both direct inhalation of smoke and second-hand smoking are known risk factors for the development of the disease.
The actual role of smoking, however, is blurred by the fact that many smokers also have other lifestyle characteristics that put them at higher risk of lung cancer.
What’s more, not all smokers get lung cancer. Whether a patient does or not depends heavily on their genetics, age, and other lifestyle factors.
Non-Smoking Related Causes
There are multiple non-smoking-related causes of lung cancer. These include:
Many patients have a high lifetime exposure to asbestos and radon – both of which are cancer-causing substances.
Asbestos is a material that builders used in the past to insulate buildings. Radon is a radioactive substance found in high concentrations underground.
Both these chemicals may aggravate – or add to – the damage already done by smoking.
You don’t even have to smoke to get lung cancer. Just breathing in somebody else’s fumes over a long period can lead to the development of the disease.
Genetics may also play a role in lung cancer development. Scientists think that gene changes in lung cell DNA can lead to abnormal cell growth and the development of tumors. Interestingly, genetic lung cancers are often different from those that develop from smoking.
Air pollution is also a risk factor. Diesel exhaust fumes, for instance, can lead to lung cancers in people who don’t smoke (and who aren’t exposed to second-hand smoke).