Carl Brahe
Radon has long been thought to be the second leading cause of lung cancer. A 2009 World Health Organization (WHO) study combined data from studies in North America, China and Europe and found that radon is not safe at any level and increasing levels increase the risk for lung cancer. Radon is considered to be the number one cause of lung cancer in people who have never smoked cigarettes.
Radon is an ionizing radiation that release particles called free radicals that can collide with lung cells causing DNA damage. Free radicals are uncontrolled atoms or molecules that are missing an electron. This causes them to be attracted to other cells in its search for an electron. Collisions with a free radical causes lung cell DNA damage that can cause a mutation that may be passed on to other cells. If the mutations are reproduced cancer may result.
The WHO study reexamined the results of radon studies around the world with ordinary populations. Using verifiable, long-term radon levels in homes worldwide, rates of cancer were documented among smokers and non-smokers. It was found that the higher the level of radon the higher the occurrence of lung cancer in non-smokers. WHO Radon Handbook
Radon levels may vary from house to house. You may have high levels while your neighbor in an identical house may not. Radon levels may vary from hour-to-hour. The EPA recommended maximum level is 4pCi/l is based on average annual radiation. Almost all testing done is short term, usually 2-7 days. Short term test kits are available at your local hardware store. Longer term test kits are more difficult to find. You can order them through Kansas State University at a discount price.
If you discover you have high radon levels in your home or business there are ways to fix it. Below is a table from the WHO Radon Handbook that presents some common ways to reduce radon levels along with cost to install and to operate.
The EPA offers a Consumer's Guide to Radon Reduction. All systems for reducing radon in living spaces either remove the radon from under the building and exhausts it above the roof, or increases the air pressure inside the building so that it is greater than the outside air pressure preventing vapors from entering. Sealing entry ways into the building is also important. Sealing cracks, joints and seams along with adding a vapor barrier, if possible, also decreases radon entry.
More houses and commercial buildings are being built with practices to decrease radon entry, but most have no radon systems, passive or active. The EPA provides information for home buyers and sellers and a guide to protecting your family from radon exposure. They also provide a web page with questions & answers about radon.
The evidence is in. Radon is dangerous to your health no matter where you live in the world. Smokers and non-smokers worldwide have more lung cancer where they are exposed to more radon radiation. Smokers and non-smokers have less lung cancer where they are exposed to lower levels of radon. It is likely that radon causes other health problems as well.