Menu Close
Find a doctor
Search Button

Causes of Lung Cancer: How to Avoid Them

Lung cancer is one of the most common cancer types worldwide. Lung Cancer in the Philippines is the leading cause of cancer-related deaths among men and is the third for women. In the Philippines, the Global Cancer Observatory (GLOBOCAN) recorded 17,255 cases of lung cancer and 15,454 deaths due to the disease in 2018.

While smoking is linked to lung cancer, it is not the only risk factor that leads to developing the dreadful disease. In fact, even non-smokers can be diagnosed with lung cancer.

It is important to learn about the different causes of lung cancer and avoid them.

Cigarette Smoking

Tobacco smoke contains over 7,000 chemical compounds 2, many of which have been shown to be cancer-causing, or carcinogenic. The risk of developing lung cancer decreases each year following smoking cessation as normal cells grow and replace damaged cells in the lung.

The risk of lung cancer increases with the number of cigarettes smoked over time. For example, a person who has smoked two packs of cigarettes per day for 10 years has a 20 pack-year smoking history. While the risk of lung cancer is increased with even a 10 pack-year smoking history, those with 30 pack-year histories or more are considered to have the greatest risk for the development of lung cancer.

Second-hand smoking

Second-hand smoking is defined as the smoke coming from a burning cigarette and the smoke exhaled by the smoker. This causes thousands of heart disease and lung cancer-related deaths annually.

The inhalation of second-hand tobacco smoke from other smokers that may be sharing living or working quarters with a non-smoker is also an established risk factor for the development of lung cancer. The longer you are exposed to smoke, the more your body will absorb higher amounts of harmful and carcinogenic substances found in tobacco. Research has shown that non-smokers who reside or work with a smoker have a 20% to 30% increase in risk for developing lung cancer.

Exposure to asbestos and other harmful substances

Inhaling asbestos fibers in the air can occur during the mining and processing of asbestos, when making asbestos-containing products, or when installing asbestos insulation. Exposure to asbestos fibers can occur through inhalation or by swallowing. Materials with asbestos tend to breakdown and create dust particles which linger in the air.

On-the-job exposures to chemicals and substances such as asbestos are significant causes of lung cancer. Some industrial chemicals associated with lung cancer include arsenic, chromium compounds, nickel compounds as well as dust and fumes.

Radon gas exposure

Radon exposure is the second-leading cause of lung cancer.7 Radon is a colorless, odorless radioactive gas that exists naturally in soil. It comes up through the soil and enters buildings through small gaps and cracks.


Having a family history of lung cancer, especially of a first-degree relative (mother or father) may increase the risk of developing the disease as well. The medical history of your family is an important fact you must tell your physician. Genes may play a role in DNA changes, which is why some people inherit the reduced ability to get rid of certain cancer-causing substances like those found in tobacco smoke.

Air Pollution

In 2013, the International Agency for Research on Cancer (IARC) identified outdoor air pollution as a cause of cancer. Outdoor air pollution includes diesel engine exhaust, solvents, metals, and dust. Frequent exposure to polluted air may also lead to increased risks for other diseases, such as respiratory and heart diseases.

How to avoid the causes of lung cancer?

As it is often said, prevention is more beneficial in fighting diseases like lung cancer. Identifying these causes is one step closer to protecting yourself and your loved ones from possibly acquiring the disease. Here are some practical steps to take so you can significantly reduce the risk of developing lung cancer:

  1. Avoid smoking. If you’re a smoker, quit this habit.
  2. When someone is smoking near you, whether a stranger or a family relative, ask them politely to move to a designated smoking area. Otherwise, if you can leave the area, do yourself a favor and avoid inhaling second-hand smoke.
  3. Wear a facial mask if you know that you will be traveling to a place where air pollution is high.
  4. Shift to a healthier diet and lifestyle. Make sure to eat food, like fruits and vegetables, which are rich in vitamins.
  5. If you are working with chemicals and other hazardous materials, inquire about the possible risks and seek appropriate health safety measures to protect yourself.
  6. Subject yourself to regular screening if you have a family history of cancer, or are exposed to the aforementioned risks.

Lung Cancer in the Philippines

Lung cancer in the Philippines ranks second as the most prevalent cause of cancer-related death. In 2018, over 17,0004 individuals were recorded to have lung cancer, second only to breast cancer. At present, biomarker testing and immunotherapy in the Philippines are available but not yet covered by health insurance policies. The need for studies on Health Impact Projection are needed to show the need for access to innovative testing and treatment options (perhaps by means of government subsidy as proven by South Korea) can help increase patient survivorship.

To date, lung cancer patients can still apply for an immunotherapy treatment subsidy from the Philippine Charity Sweepstakes Office (PCSO). There are also other medical assistance in the Philippines that you can check in our previous article: cancer-medical-assistance-in-philippines.

Lung cancer is preventable and treatable if detected at its early stages. Do not become a statistic. Knowledge and action are keys toward protecting yourself and your family.


1. International Association of Cancer Registries. Global Cancer Observatory. Philippines Fact Sheet. Accessed

March 22 2019.

2. Smoking & Tobacco Use. Center for Disease Control and Prevention.

Accessed 23 April 19.

3. Secondhand Smoke: Dangers. Cleveland Clinic. Accessed 23 April 19.

4. How air pollution can cause cancer. Cancer Research UK.

5. Asbestos and Cancer Risk. American Cancer Society.

Accessed 23 April 2019.

6. Lung Cancer. Mayo Clinic.
Accessed 23 April 2019.

7. Radon and Cancer. American Cancer Society.
Accessed 28 April 2019

8. What Causes Lung Cancer. American Lung Association.

Accessed on February 1, 2019;

9. What Causes Non-Small Cell Lung Cancer. American Cancer Society.

Accessed 23 April 2019.


Share This

Copy Link to Clipboard