How Radon Enters a Home
The second leading cause of lung cancer in both the United States and Canada may be lurking somewhere inside your home.
It’s a potential health threat that can catch people by surprise, says Dr. Christopher Delp, a physician at St. Luke’s Regional Trauma Center in Duluth. In his job, Christopher may find himself making the initial diagnosis of lung cancer during an emergency room visit. “If people come in with a chronic cough or something like that, we often are on the front line.”
For people who don’t smoke, the leading cause of lung cancer, a question often arises if cancer is diagnosed, Christopher says.
“In a non-smoker, that’s their first question: ‘How can I have lung cancer? I don’t smoke.’”
The answer is not secondhand smoke, another obvious suspect. The second most common answer to that question comes in the form of an invisible, odorless, radioactive gas that naturally seeps from the earth – radon. Inhaled over an extended period of time, radon’s radioactive particles can damage the cells that line the lung.
It’s estimated that 15,000 to 20,000 of the nearly 160,000 lung cancer deaths a year in the United States can be attributed to radon exposure. In Canada, an estimated 20,000 lung cancer deaths – about 16 percent of the annual total – involve radon.
Radon is virtually everywhere and while no safe level has been established, it’s known that your greatest risk of accumulated exposure comes inside your home, where you may spend the most time. How much radon is in your home depends on many factors – including where you live. None of the shores around Lake Superior rank among the highest risk areas, but most fall into the intermediate category. The farthest reach of Michigan’s eastern Upper Peninsula has a low ranking for U.S. risk areas, but that’s no guarantee that an individual home doesn’t have high levels of radon gas.
Many areas just outside the Lake Superior watershed, however, such as western and southern Minnesota, rank for high risk.
The good thing about radon risk is that it’s easy to test your home and there are ways to reduce the gas in the house.
Radon gas levels in a house can be tested with either of two kits: short-term (two to seven days) or long-term (90 days). These range in price from $5 to $25 (US) and can be purchased from local, state or provincial health departments (see Good to Know). Make certain the price includes a laboratory analysis. Private contractors also will do the tests, though it is generally more expensive.
The short-term test can determine a snapshot of radon in the house, but only the long-term test reveals the likely annual average concentration. This test is most effective if it spans a cooling and heating season.
Picocuries per liter (pCi/L) is the unit by which levels of radon or radioactive gas are measured. If your home registers more than 4 pCi/L for radon gas as an annual average, experts recommend taking steps to reduce that level.
How you reduce that level depends on your home’s foundation – basement, slab on grade or crawl space. Methods include sealing off entry points and ventilation through a passive or active system. Such remediation can cost from $500 to $2,500 (US).
Reducing high exposures can be important for everyone, but especially for those who live for decades in the same home and for those who do smoke.
Prudence, not panic, is the way to approach radon as a health risk, says Christopher. “We know that radon will increase your risk of cancer. How much, we don’t know. You have to keep it in perspective – the vast majority of the people won’t get cancer. But you can modify your risk, and you should.”
Good to Know
Radon Awareness Month comes in November for Canada and January for the United States.
Below are resources for finding radon test kits, additional information and certified radon contractors.
Michigan Department of Environmental Quality
800-723-6642, michigan.gov/deq
Wisconsin Department of Health Radon Program
888-569-7236, dhs.wisconsin.gov/radiation/radon
Minnesota Department of Health Indoor Air Program
800-798-9050, health.indoorair@state.mn.us, health.state.mn.us
Health Canada Radiation Health Assessment Division
613-946-6384, radon@hc-sc.gc.ca, www.hc-sc.gc.ca