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Lung Cancer - Step 2: Which Risk Factors May Apply to You? email this page to a friendemail this page
In this step, you explore how to know if any of the known risk factors for lung cancer apply to you.  If you need to review the basics, check out What Are Risk Factors?  and What is Risk Exposure?
Find out more:
Cigarette smoking and cancer
The truth about “light” cigarettes
Cigar smoking and cancer
Secondhand smoke
Radon and cancer
Asbestos exposure

Understanding Lung Cancer Risk Tool
Check the risk factors that apply to you to build your own list. Then go to Step 3 to learn what you can do to reduce your risk for factors in your list. After you build your list, you can print it out and take it with you to your doctor.

Lung Cancer Risk Factor

How Will I Know?

Does This Risk Factor
Apply to Me?

Cigarette smoking

If you smoke cigarettes, you are at increased risk for lung cancer. Cigarette smoking causes 87 percent of lung cancer deaths. Your risk increases with total lifetime exposure to cigarette smoke. This includes:

  • The number of cigarettes you smoke each day
  • The intensity of your smoking (the size and frequency of puffs)
  • The age at which you began to smoke
  • The number of years you have smoked
  • Your exposure to secondhand smoke.
"Light" cigarettes do not reduce the health risks of smoking.

Cigar smoking

If you smoke cigars, you are at increased risk for cancer of the lip, tongue, mouth, throat, larynx, lung, and esophagus. If you smoke cigars daily, particularly if you inhale, you are at increased risk for developing heart and lung disease. Lung disease itself is a risk factor for lung cancer.

Like cigarette smoking, your risk from cigar smoking increases with increased exposure.

Environmental tobacco smoke

Environmental tobacco smoke, commonly known as secondhand smoke, is a risk factor for lung cancer. It is a combination of smoke emitted from the burning end of a cigarette, cigar, or pipe, and smoke exhaled by the smoker.

If you are a nonsmoker who lives with smokers in a home where smoking is allowed, you are at the greatest risk for suffering the negative health effects of secondhand smoke exposure (lung cancer, nasal sinus cancer, respiratory tract infections, and heart disease).

If you are a nonsmoker, separating yourself from smokers may reduce, but will not eliminate, your exposure to secondhand smoke.


Radon, an odorless, colorless, radioactive gas, is present in nearly all air. While everyone breathes in low levels of radon in every day, people who breathe in high levels of radon are at an increased risk for developing lung cancer.

Radon is the second leading cause of lung cancer in the United States and is associated with 15,000 to 22,000 lung cancer deaths each year.

Radon can enter your home through cracks in floors, walls, or foundations, and collect indoors. It also can also be released from building materials, or from water obtained from wells that contain radon. Radon levels can be higher in homes that are well insulated, tightly sealed, and/or built on uranium-rich soil. Because of their closeness to the ground, basement and first floors typically have the highest radon levels. Testing is the only way to know if your home has elevated radon levels.


If you have had or currently have substantial exposure to asbestos, you are at increased risk for lung cancer.

Nearly everyone is exposed to asbestos at some time during his or her life. However, most people do not become ill from their exposure. People who become ill from asbestos are usually those who are exposed to it on a regular basis, most often in a job where they work directly with the material or through substantial environmental contact.

You may have been exposed to asbestos fibers if you worked in:

  • Shipbuilding trades
  • Asbestos mining and milling
  • Manufacturing of asbestos textiles and other asbestos products
  • Insulation work in the construction and building trades
  • Brake repair.

Currently, asbestos is used most frequently in gaskets and in roofing and friction products. Government regulations and improved work practices have made today’s workers (those without previous exposure) likely to face smaller risks than those who were exposed in the past.

If you are a smoker who is also exposed to asbestos, you have a greatly increased risk of developing lung cancer.

Lung diseases

If you have had certain lung diseases, such as tuberculosis (TB), you are at increased risk for developing lung cancer. Lung cancer tends to develop in areas of the lung that are scarred from TB.

Personal history

If you have had lung cancer once, you are more likely to develop a second lung cancer compared with a person who has never had lung cancer.

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