Several cancers are closely related to specific risky activities. For example, many cases of liver cancer can be attributed to excessive consumption of alcohol over a prolonged period of time. However, there is perhaps no stronger link between a certain cancer type developing as a result of a specific risky activity than the clear association between lung cancer and smoking. In the USA alone, it’s estimated that between 80% and 90% of lung cancer deaths can be attributed to smoking. This obviously means that there are other risk factors that can increase the likelihood of lung cancer developing and indeed, there are several other causes of liver cancer aside from excessive alcohol consumption. But the link between these activities and the increased risk of certain cancers cannot be ignored. Smoking is believed to increase the risk of up to 16 different types of cancer, with lung cancer being the type that most people associate with the habit. But what else can cause lung cancer? In this article, we will explore the other, less common causes of this disease.

What is Lung Cancer?

Cancer occurs when certain abnormal cells in the body uncontrollably grow and divide, creating more abnormal (cancerous) cells). The classification of different cancer types relates to where cancer begins, therefore lung cancer refers to when cancer begins in the lungs. Lung cancer (and other types of cancer) can spread to other organs within the body and the lymph nodes. The risk of this occurring is enhanced if prompt treatment is not received. There are two main types of lung cancer, small cell lung cancer and non-small cell lung cancer. Small cell lung cancer is the more aggressive form of the disease and accounts for approximately 10-15% of all lung cancer cases. Non-small cell lung cancer is more common (around 85% of all lung cancer cases) and its development is closely associated with smoking.

Causes of Lung Cancer

Smoking is the leading cause of lung cancer worldwide. Not only are smokers themselves at risk of developing the disease as a result of their habit, but non-smokers who are routinely exposed to second-hand smoke are also more likely to develop lung cancer, compared to those who are infrequently or never exposed to second-hand smoke.

Avoiding tobacco altogether is widely regarded as an effective way of reducing one’s personal risk of developing lung cancer as well as the many other cancers and conditions associated with smoking.

Whilst smoking is by far the leading cause of lung cancer, there are numerous other risk factors associated with the disease.


There is evidence to suggest that air pollution can increase the risk of lung cancer. This is of particular concern to individuals who live in cities with consistently high levels of air pollutants such as particular matter (PM2.5), nitrogen oxides and ozone.


This colourless, odourless and tasteless gas is naturally found within the soil. Exposure to this radioactive element can increase the risk of lung cancer, in fact, it is the second most common cause of the disease in many countries, including the United States of America. The most common way that people are exposed to this gas is from cracks and holes in the foundations of homes. The gas seeps up from the ground and into the house and the air you breathe. Those who smoke cigarettes and are exposed to radon are even more at risk of getting lung cancer.

Hazardous Chemicals

Chemicals including arsenic, uranium, asbestos and chromium can increase the risk of lung cancer, when individuals are exposed to them, particularly over a long period of time. Often the people most at risk of this particular cause are those who work with hazardous chemicals as part of their employment. However, asbestos is an example of a hazardous chemical that has been frequently used in the construction of residential houses and commercial buildings in most countries throughout the world. Many nations these days now have laws in place which ban the use of asbestos in new construction projects, but there are still certain regions whereby it is not so tightly regulated. Strong evidence suggests that the inhalation of asbestos fibres can lead to a variety of respiratory-related health conditions including lung cancer. This discovery and the subsequent public recognition of the dangers associated with asbestos led to it being banned for use in construction in many countries throughout the world.


There are many things that one can do to reduce their personal risk of developing lung cancer. If you don’t smoke and make an effort to avoid exposure to second-hand smoke, dangerous chemicals and unclean air, you should certainly be better placed to minimise your risk. However, there is, unfortunately, a risk factor that is beyond the control of the individual and this relates to genetics.

A family history of lung cancer could result in an individual being more prone to also developing it themselves.