Radon in homes

The test kit is used to detect radon in home basements. 

Cohen, B.L., A National Survey of Radon in Homes and Correlating Factors, Health Phys. (in press) (1986b). 

Homes with cracked concrete slabs or dirt basements are at risk for radon contamination. Radon is generated just under the surface of the Earth and can seep through the floors and walls. If the ventilation is poor in the basement, the gas can accumulate to a dangerous level. Inexpensive kits that measure the levels of radon in homes and businesses are available commercially. 

Though other parts of my interviews were widely reported, I know of no case where the comparisons between radiation from radon in homes with radiation from nuclear power were included. They certainly never got national attention. For the media, nuclear power was the most dangerous source of radiation, and there was no way they were going to report otherwise—that would be like an attack on their religion. Of course this was a simple extension of their refusal to compare radiation from nuclear power with that from natural sources and medical X rays. 

I often wondered whether the reporters were afraid to include my points about nuclear power, or whether they were edited out at a higher level. In any case, the media and the public view radiation from nuclear power and from radon in homes as entirely different and unrelated subjects. I repeatedly explained to reporters that when a cell in our bodies is hit by radiation, there is no way for it to know whether that radiation originated from nuclear power operations or from radon, but somehow that explanation never got reported. 

My research eventually convinced me (and a great many others) that radon in homes is very much less harmful than the widely publicized estimates that were based on extrapolating from the number of excess cancers seen in uranium miners who had very high radon exposures. Those estimates were (and are) based on the assumption that the cancer risk from radiation is proportional to the dose, the so-called linear-no threshold theory (LNT). 

National Radiological Protection Board (1990). Human exposure to radon in homes. 

The results of the studies on miners have been used as a basis for estimating the risks to the general public from exposures to radon in homes. There is considerable controversy over this topic. Although the health effects due to the high radon exposures experienced by the miners have been well established, the risks at the lower exposure levels in residences are difficult to establish due to uncertainties in the dose-response curve and the confounding effects of smoking and urbanization. The reader is referred to extensive documentation by the National Academy of Sciences (1998) and the National Institute of Health (1994) for more information. 

Radon is a well-known air pollutant today. It is formed in rocks and soil where uranium is present. As a gas, radon tends to drift upward out of the ground. If a house or building has been built above soil containing uranium, radon may collect in the stmcture. The U.S. Environmental Protection Agency (EPA) regards the presence of radon in homes and offices as a serious health problem. 

The EPA has studied the problem of radon in homes and offices. The agency estimates that 1 in 15 U.S. homes has radon levels that are too high. Radon can enter homes in a variety of ways, including through cracks in walls and floors as well as via the water supply. 

A radon-reduction system lowers the concentration of radon in homes by venting the radon gas from the home to the outside environment... 

Edling C, Kling H, Axelson 0. 1984. Radon in homes-a possible cause of lung cancer. Scand J Work Environ Health 10 25. 

At about the same time, the media was writing about the risks associated with indoor radon pollution and quoting federal warnings that radon in homes could cause five thousand to twenty thousand lung cancer deaths a year. An article in the New York Times asserted ... 

These radon concentrations in the homes were orders of magnitude less than the levels exposing workers in the uranium mines in Czechoslovakia, and hence the results imply that low doses are not only harmless but beneficial to avoiding lung cancer. Nevertheless, to this day (2015) the EPA continues to ignore the results of their own data and places information spots on the broadcast media about the dangers of radon in homes, and what actions homeowners should take to reduce the radon concentrations. 

The average level of radon in homes is lower than 1 picocurie/L of air. A picocurie (10 curie) is equivalent to the radioactive decay of 2 radon nuclei per minute. The Environmental Protection Agency recommends an upper limit of 4 picocuries/L for indoor air, and it has been estimated that 99% of the homes in the United States have levels below this value. However, new studies reported by the World Health Organization have led to recommendations that new upper limits of 2.7 picocuries/L be established. This level is 33% lower than the current upper limit EPA recommendations. 

Levels of radiation much higher than 4 picocuries/L have been found in some homes. The highest recorded level of radioactivity from radon in a home was 2700 picocuries/L of air. This was found in a home in Pennsylvania that was built on soil rich in uranium-238. The level of radon in home air can be minimized by sealing the entry points and providing good ventilation. 

National Radiological Protection Board, NRPB (1990). Human exposure to radon in homes. Doc. NRPB 1, 17-32. National Research Council Committee on the Biolt ical Effects of Ionizing Radiations, NRC (1988). Health Risks of Radon and Other Interrudly Deposited Alpha Emitters (BEIRIV). National Academy Press, Washington, DC. Nero, A.V. (1988). Estimated risk of lung cancer from exposure to radon decay products in U.S. homes A brief review. Atmos. Environ. 22, 2205—2211. 

Relatively inexpensive kits are available to test for radon in your home. The EPA recommends action for levels of 4 pCi/L or above. Ways to reduce radon in homes range from the relatively simple, keeping a basement window open, to more costly measures such as installing a radon ventilation system. 

Essentially all of the radon in homes is radon-222, a decay product of naturally occurring radium-226. Radium-226, in turn, is part of the naturally occurring decay series from uranium-238 to lead-206. (See p. 436 for more on these series.) So radon-222 is released by rocks, soil, and groundwater and enters homes from the soil, eventually seeping through floor drains, joints, and/or small cracks in basement floors and walls. It is now estimated that every square mile of soil 6 inches deep contains about 1 g of radium, which gradually decays to radon. 

Radon in Homes Recent Developments, C. H. Atwood, Journal of Chemical Education, 55(10), 1436-1439 (2006). 

Inert gases. Neon is used in advertising signs. The gas in tubes adds both color and light. The test kit is used to detect radon in home basements. 

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