Written by Kittu Rao, M.P.H. (Assistant, CEHN); Edited by Nsedu Obot Witherspoon, M.P.H. (Executive Director, CEHN)
Radon is a naturally occurring radioactive gas that seeps out of rocks and soil. Radon is released from decayed uranium that has been in the ground since the time the earth was formed. Radon flows from the soil into outdoor air and also into the air in homes from the movement of gases in the soil beneath homes and other building such as schools, child care facilities, and hospitals. Radon can also be found in groundwater and can eventually make it to your tap. Typically, radon gets into the building by moving up through the ground and then through the cracks and other holes in the foundation. As a result, a building, such as a childcare center, can trap radon inside and cause the gas to build up and reach a harmful concentration. Radon concentrations tend to vary from every building; including offices, homes, hospitals, and childcare centers. Outside air typically contains very low levels of radon, but it builds up to higher concentrations indoors when it is unable to disperse.
The highest levels of radon, which is an average indoor radon screening level greater than 4 pCi/L (picocuries per liter), is predominantly found in the northeast, from Maine to Maryland, and in the upper Midwest and central plains/Ohio Valley region of the country. The lowest average indoor radon screen levels, which is less than 2 pCi/L is found all along the southeast, parts of central California, Texas, and parts of the Mid-Atlantic region.
All major health organizations in the U.S. have confirmed that over exposure of radon leads to lung cancer. [1] Although radon is chemically inert and electrically uncharged, it is radioactive, which means that radon atoms in the air can spontaneously decay, or change to other atoms. Since you can not see, smell or taste radon, one does not know when being exposed to the harmful gas. When the resulting atoms are formed, they are electrically charged and can attach themselves to tiny dust particles in indoor air. These dust particles can easily be inhaled into the lung and can adhere to the lining of the lung. Alpha radiations can disrupt DNA of these lung cells and cause a mutation, thereby leading to cancer. Lung cancer is the most important cancer hazard that is posed by radon in indoor air.
Radon accounts for more than half of our total average annual exposure to radiation, about 200 out of 360 millirem per year.[2] Radon ranks highly among other preventable causes of death, including drunk driving, drowning, and fires. Additionally, the death risk to the average person from radon gas at home is 1,000 times higher than the risk from any other carcinogen or toxin regulated by the FDA or EPA.[3]
According to the US Environmental Protection Agency, radon is listed as one of the most serious environmental health problems in the United States.[4] Radon is responsible for 20,000 lung cancer deaths each year.[5] It is the leading cause of lung cancer among non-smokers, and about 2,900 fatalities non-smokers die from lung cancer caused by radon exposure each year.[6] According to the Office of the Surgeon General: “Indoor radon gas is a serious health problem in our nation that can be addressed by individual action. Unless people become aware of the danger radon poses, they will not act. Millions of homes are estimated to have elevated radon levels. Fortunately, the solution to this problem is straight-forward. Like the hazards from smoking, the health risks of radon can be reduced.” [7]
Radon is a problem among children for several reasons. There is a longer period between exposure and the development of cancer. Children have smaller lungs and higher breathing rates.[8] Children’s biological systems are still developing during their first years of life making them more susceptible to harm. Doctors say that, by the age of 10, a child receives twice the lung dose of an adult who’s been exposed to radon for the same length of time.[9] Children have different lung architecture and breathing patterns, resulting in a somewhat larger dose of radiation to the respiratory tract. Children also have longer latency periods in which to develop cancer. Hofmann reported that the radon dose was strongly dependent on age, with a maximum value reached at about the age of 6 years. [10] Since children spend up to 70% more time inside than adults, more children will be exposed to this carcinogen over time.[11] The relative risk from domestic radon exposure is also higher for children because they spend more time at home and/or in the basement or lowest level of house.[12] Because of the latency time for cancer to develop and the cumulative nature of radon risk through time, there is very little possibility that someone could get lung cancer from radon before age 35, although exposures before that age contribute to the risk at later ages. Radon is a silent killer, since people can’t tell if they’re being exposed and its effects are more hazardous for children than adults.
More importantly, any building (such as homes, office buildings, childcare facilities, schools and hospitals) can have dangerous levels of radon. According to the EPA, a nationwide survey of radon levels in schools estimates that nearly one in five has at least one schoolroom with a radon level that is higher than the recommended levels.[13] This is alarming since 60% of young children spend their day in some form of child care setting and are more likely to witness long-term exposure to the carcinogen, as compared to adults.[14]
Being that radon, is naturally occurring, it cannot be entirely eliminated from our homes and buildings. Radon testing must be performed in homes and any other facility where children spend most of their time, to prevent severe health effects in children. For those people who work in offices, you have to follow guidelines to test your office to ensure there are not dangerous levels of radon in the building. It is important to take the appropriate steps in order to make sure the levels are normal. If you find a high level, which is at or higher than 4pCi/L, (picocuries per liter), you should take appropriate steps to reduce the radon to a safe level. Radon is dangerous if not taken care of. It is imperative that the building levels of radon be reduced to normal, since many people spend a large amount of their time in this area, and you want it to be a safe-breathing zone.
The EPA and the office of the Surgeon General recommend that all homes be tested for radon. It is a quick and painless test, but it could save your house from further repairs and will ease your minds. For those who have radon present in homes, the annual average radon level must be below 4 pCi/L.[15] The only way to detect radon is through testing. Common test kits can include: charcoal canisters (short term, 2-7 days), e-perm (short/long term), alpha track detectors (long term, 91-365 days), and charcoal liquid scintillation devices.[16] A radon test kit can be purchased for around $20. Make sure you follow the directions of the kits closely because the length of time the kits can remain open varies. Place the test kit in the basement or lowest lived-in level of a home making sure it is not near drafts, open windows, or fans. After the specified amount of time mail the kit immediately to the manufacturer to be analyzed. The main issue with radon testing is that radon levels tend to vary every day. Therefore, it is best to do two short-term tests for at least 48 hours, either at the same time or one after one another, to get the average. Because no level of exposure to radon is considered safe, the EPA also recommends that the public consider fixing their homes if their levels are between 2pCi/L and 4pCi/L.[17] Fixing buildings to reduce radon levels may involve sealing cracks in the foundation or ventilating the area under the foundation. Expert assistance should usually be obtained when radon reduction is being attempted. Currently, the Environmental Protection Agency has a new map out that shows radon potential—high, medium, or low level. The agency also works with schools to find the best way to lessen radon exposure.[18] Short term radon testing lasts one to two days, however long term radon testing in a house can be from 3 to 12 months long.
If you are interested in finding a qualified radon service professional to test or mitigate your home, or you need to purchase or have questions about a radon measurement device, you should:
1. Contact your State Radon Contact (http://www.epa.gov/iaq/whereyoulive.html), just click on your state to get contact information) to determine what are, or whether there are, requirements associated with providing radon measurement and or radon mitigations/reductions in your State. Some States maintain lists of contractors available in their state or they have proficiency programs or requirements of their own.
2. Contact one or both of the two privately-run National Radon Proficiency Programs (listed below alphabetically) who are offering proficiency listing/accreditation/certification in radon testing and mitigation. (Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government).
Resources
- En Español National Hispanic Indoor Air Quality Hotline 1-800-SALUD-2 (1-800-725-8312): This agency will provide people with radon-related information in Spanish. They also distribute kits with bilingual instructions
- National Safety Council http://www.nsc.org/issues/radon/ This site provides information about testing for radon in homes, offices, schools and other buildings.
- Environmental Protection Agency http://www.epa.gov/radon/pubs/consguid.html: This site will guide you through picking out a contractor and starting to protect your home.
- EPA Radon USA Map: (http://www.epa.gov/radon/zonemap.html#more%20about%20the%20map).
- National Radon Information Line 1-800-SOS-RADON (1-800-767-7236): Call this number to learn more about ways to test and protect yourself from radon.
- The National Environmental Health Association (NEHA)
National Radon Proficiency Program
Toll Free: (800) 269-4174 or (828) 890-4117
Fax: (828) 890-4161 - National Lung Association
http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E&b=35395
- Children’s Environmental Health Network
www.cehn.org
202-543-4033
[1] http://www.cancer.org/docroot/PED/content/PED_1_3x_Radon.asp
[2] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007
[3] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007
[4] U.S. Environmental Protection Agency. Radon. Available at: http://www.epa.gov/radon/index.html Accessed 18 October 2007.
[5] U.S. Environmental Protection Agency. Radon. Available at: http://www.epa.gov/radon/index.html Accessed 18 October 2007.
[6] U.S. Environmental Protection Agency. Radon. Available at: http://www.epa.gov/radon/index.html Accessed 18 October 2007.
[7] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007
[8] University of Minnesota. Radon for Kids. Available at www1.umn.edu/eoh/hazards/hazardssite/radon/radonforkids.html Accessed 26 August 2007.
[9] University of Minnesota. Radon for Kids. Available at www1.umn.edu/eoh/hazards/hazardssite/radon/radonforkids.html Accessed 26 August 2007
[10] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007.
[11] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007.
[12] University of Minnesota EOH. Radon Risk Assessment. http://enhs.umn.edu/hazards/hazardssite/radon/radonriskassessment.html Accessed 18 October 2007.
[13]U.S. Environmental Protection Agency. Radon. Available at: http://www.epa.gov/radon/index.html Accessed 18 October 2007.
[14] Children’s Enivronmental Health Network. Healthy Environments for Child Care Facilities and Preschools program. 2008
[15] University of Minnesota. Radon for Kids. Available at www1.umn.edu/eoh/hazards/hazardssite/radon/radonforkids.html Accessed 26 August 2007.
[16] Southface. Radon Resources and FAQ. 2006. Available at http://southface.org/web/resources&services/radon/sf_radon-menu.htm. Accessed 28 February 2007.
[17] U.S. Environmental Protection Agency. Radon. Available at: http://www.epa.gov/radon/index.html Accessed 18 October 2007.
[18] University of Minnesota. Radon for Kids. Available at www1.umn.edu/eoh/hazards/hazardssite/radon/radonforkids.html Accessed 26 August 2007.