About 80% of lung cancers occur in smokers or former smokers—but 20% of lung cancers occur in those who have never smoked, which can catch people off guard.
“A variety of environmental factors, aside from smoking, can contribute to someone’s lung cancer risk,” says Mohan Kulkarni, M.D., a thoracic surgeon at Henry Ford Health. “But the type of lung cancer that nonsmokers develop often differs from the type of lung cancer that smokers develop. While lung cancer in smokers forms as a roundish spot, lung cancer in nonsmokers is diffused or less concentrated to one area. Lung cancer in nonsmokers is also usually slower growing.”
Here, Dr. Kulkarni shares environmental risk factors for lung cancer aside from smoking—and how to reduce your exposure.
1. Radon gas
Exposure to radon is the second leading cause of lung cancer, after smoking. It’s a radioactive gas that’s colorless, odorless and naturally occurring in the soil. When it’s outside, radon isn’t usually a health threat because it disperses rapidly, says the Environmental Protection Agency (EPA). The problem occurs when it enters through cracks in the foundation of someone’s basement, becoming trapped inside.
The only way to know whether you have radon in your basement is to get your house tested. It’s a service that’s usually offered during a home inspection, but you can also reach out to a professional to get radon testing or buy a DIY home testing kit. If radon levels are a problem, radon service professionals can implement an underground ventilation system or increase air changes in your home.
2. High-temperature cooking
Asian females are a rising group of never-smokers who are developing lung cancer. This is thought to be the case because frequently cooking with oil at high heat—stir-frying, for example—creates carcinogens that are detrimental to the lungs.
To decrease your lung cancer risk, ensure your kitchen is well-ventilated and switch up your cooking methods. Steaming (which also helps retain more nutrients over frying) and even microwaving vegetables can be healthy cooking alternatives.
Asbestos, a mineral fiber that’s found in rock and soil, is a dangerous substance that can cause lung cancer. It was used in building construction for years because it’s durable and heat resistant. While it’s now banned in many instances, it can often be found in old homes and buildings as wall insulation, vinyl floor tiles, roofing and more. This isn’t an issue if it’s left intact—but if you plan on doing construction projects, disturbed asbestos fibers can get into the air and harm your lungs.
Before embarking upon construction projects—especially if you live in an old home—have a trained professional determine whether you have asbestos and where it is. They can safely remove it so it doesn’t become an issue.
4. Second and thirdhand smoke
Since smoking can cause lung cancer, it makes sense that secondhand smoke can also contribute to lung cancer, especially if you live with someone who smokes. But it’s not just secondhand smoke: thirdhand smoke can also be a risk factor for lung cancer.
“Thirdhand smoke is just as bad for you as secondhand smoke,” says Dr. Kulkarni. “When someone smokes, cancer-causing chemicals cling to surfaces like clothing, hair, rugs, carpets, furniture, vehicles, bedding, drapes and walls.” With time, these chemicals build up on surfaces and they’re not easy to remove—you can’t just air out a room with fans or by opening windows.
Washing walls and ceilings with detergent and very hot water may get rid of thirdhand smoke. Clothing and bedding can be cleaned in a washing machine, although they may require a few cycles. Carpets and furniture, however, might need to be replaced. And if thirdhand smoke has gotten behind walls and insulation, they may need to be replaced as well.
Vehicle emissions, pollution from industrial facilities, wildfire smoke—all sources of air pollution can negatively impact the lungs if inhaled in unsafe quantities. The American Cancer Society estimates that hundreds of thousands of lung cancer deaths worldwide can be attributed to particulate matter (PM) pollution, which are particles smaller than 10 micrometers in diameter. They’re the most dangerous because they’re so small they can get deep into your lungs and bloodstream, says the EPA. Smoke from the Canadian wildfires were a major source of particulate matter last summer.
To reduce your exposure, check the air quality on airnow.gov before committing to outdoor activities. Getting an air purifier for your home can also help ensure you’re breathing in clean air indoors.
“Many people often don’t experience symptoms of lung cancer—like a worsening cough, coughing up blood, chest pain, wheezing and more—until lung cancer has progressed to stage 3 or 4, where it has spread outside of the lungs,” says Dr. Kulkarni. “If you are worried about potential environmental exposures and your lung cancer risk, don’t hesitate to talk to your doctor.”
Reviewed by Mohan Kulkarni, MD, FRCSC, a thoracic surgeon who sees patients at Henry Ford Jackson Hospital.