Why Scientists and the Public Do Not Believe in Radon Risks

Risk perceptions are the basis for radon risk decisions by both scientists and the general public. Since radon cannot be detected by any of our five senses, which most people rely upon to warn them of danger, much of the general public does not perceive radon as a significant risk. Likewise, many health physicists, with many years of training and experience in dealing with significant radiation exposures, also do not perceive radon as significant. Consequently, there is considerable apathy in the United States regarding measurement and mitigation for radon. Radiation scientists also continue to raise questions about comparisons of lung cancer risks and exposure conditions between uranium mines and homes. Some scientists are questioning whether the linear model is valid for relating documented lung cancer risks in miners to the low radon doses that may occur in homes. The collective dose concept for determining population risks from radon is also drawing skepticism from scientists and the public who do not see evidence of risks to individuals at low radon doses. Health physicists have traditionally been more concerned for man-made sources of radiation. Radon has always been considered a part of our natural radiation background and many feel that we should only be concerned for radiation exposures above natural background. Many radiation protection professionals also seem to find radon. at effective dose equivalents of 200 to 1000 mremlyear or more, less risky than occupational exposures to radiation at levels of 10 to 50 mremlyear. On the other band, alpha particle emissionsfrom radon decay products transfer more radiation energy into our body tissues than any other source of radiation, either natural or man-made. We cannot ignore this large source of radiation dose while at the same time promoting programs for radiation safety for much smaller doses from other sources. Most people do not interpret radon risks the way they are presented by radiation scientists as statistical probabilities. People generally see an activity as risky and therefore to be avoided. Or it is not risky. Most people who were concerned for radon as a health risk decided to test and mitigate their homes in the late 1980s. Less people today are as concerned for radon risks as they are for the possibility of buying a house with a radon problem which could affect them financially. Homeowners are not inclined to spend hard-earned dollars to avert "questionable" risks from radon, even when warned by the EPA and state health agencies. However, homeowners have found a way to get radon fixed without paying for it. Namely, it is common practice to require a radon test before purchasing a home. If the radon test results are above the EPA action level of 4 pCi/L, then the homebuyer demands radon mitigation by the seller as a condition of sale. Somehow, radon seems more risky and worthy of mitigation when someone else is paying for it. Radon apathy is also aggravated by news articles across the country in January 1995, which said "Radon Scare is a Costly Hoax." These news stories were based upon a publication of the National Cancer Institute in December 1994 (the Missouri Study), which news reporters claim, "unmasked the radon fraud with the help of some wicked facts." When homeowners read such stories, they are inclined to agree, because they see no evidence for radon risks. They are even more likely to agree when they hear that scientists are debating the risks of radon. Since the evidence for radon risks is not obvious to homeowners and since scientists are also debating the risks, it is easy for most homeowners to believe that the EPA is overstating the risks from radon. Despite the controversy and uncertainty in radon risks, the prudent message for radon testers and mitigators 1995 International Radon Symposium I1 1.1 to recommend to homeowners is: "Test and mitigate your home for radon according to EPA and state protocols." This message is cautious on (he side of safety and in keeping with precautions that we normally take to avert other risks, such as wearing seat belts to avoid injuries in an automobile accident.