• Some countries located in Eastern European and Asia have the highest risk of lung cancer in the world due to air pollution, according to a recent study.
• Countries such as Serbia, Montenegro, China, and Mongolia have the highest risk of lung cancer in older populations, spanning from ages 50 and older.
• In addition to air pollution, patterns of cigarette smoking in these countries can increase the risk of developing lung cancer.

A new study has found some Eastern European and Asian countries — including Serbia, Montenegro, China, and Mongolia — rank highest in the world for lung cancer risk due to their air pollution levels. Researchers also determined that patterns in cigarette smoking in a given country also contributed to increased risks of lung cancer. The findings shed further light on the connection between air pollution and lung cancer in different parts of the world.

Dr. Christine Berg and Dr. Joan Schiller presented their research at the Presidential Symposium Plenary Session hosted by the International Association for the Study of Lung Cancer on Sept. 9. “Patterns of cigarette smoking and amounts of pollution from fossil fuel energy sources are most likely the primary drivers of the variability in risk attributable to lung cancer,” according to Berg, citing the causes related to lung cancer in these countries.

The data was presented as the number of lung cancer deaths per 100,000 people. Researchers focused on two age groups for their study. For the group comprising people ages 50 to 69, these five countries ranked highest for the risk of lung cancer caused by air pollution:

• Serbia, 36.88 per 100,000
• Montenegro, 34.61 per 100,000
• North Macedonia, 30.67 per 100,000
• Bosnia-Herzegovina, 30.64 per 100,000
• Poland, 27.97 per 100,000

For the 70 and older age group, these countries ranked highest for their risk of lung cancer due to air pollution:

• China, 98.55 per 100,000
• Mongolia, 77,11 per 100,000
• North Korea, 63.45 per 100,000
• Laos, 62.07 per 100,000
• Montenegro, 61.80 per 100,000

“For comparison, in the United States the number of lung cancer deaths per 100,000 attributed to air pollution in ages 50 to 69 is 3.91 and is 13.62 for 70 and older,” Berg said.

Tobacco smoke is the leading cause of lung cancer, causing around 80 percent of lung cancer deaths. Exposure to secondhand smoke is also a well-known cause. However, lung cancer can still develop in people who have never smoked. This is likely caused by exposure to other cancer-causing agents (known as carcinogens), such as air pollution, asbestos, radon, diesel exhaust, and more. According to the World Health Organization, levels of air pollution have significantly increased in low- and middle-income countries with larger populations.

While air pollution has been a suspected cause of lung cancer for many years, the actual risk of someone developing lung cancer from it can vary in different parts of the world. This depends on a number of factors, including age, tobacco smoking, and the level of air pollution in a given country.

For the study, Berg looked at available scientific papers about indoor and outdoor pollution and the health problems they can cause. She also looked at the Global Burden of Disease database to look at lung cancer cases by country caused by air pollution.