Study Shows Radon Risk May Have Been Overstated
Previous estimates of the danger that children will get lung cancer as a result of being exposed to radon may have been overstated by as much as 20 percent, a new study maintains.
The study, completed by a panel of experts for the National Research Council, found that most studies on radon's risks are based on the experiences of underground miners. But those results, it argues, cannot be readily applied to adults and children who receive their primary exposure to radon at home.
Radon is a an odorless, colorless gas that occurs underground. It can seep into basements through cracks in a building's foundation.
The U.S. Environmental Protection Agency believes radon may cause as many as 200,000 lung-cancer deaths yearly.
The new study, released this month, indicates that radon-risk models based on miners may overestimate a child's risk of developing8lung cancer from household radon exposure by as much as 20 percent, and an adult's risk by about 30 percent.
Miners are disproportionately male and are also more likely than the general population to smoke, the study notes. Other investigations have found that the chances of developing lung cancer increase exponentially when a smoker is exposed to radon.
The panel cautioned that its findings do not imply that radon is less carcinogenic than previously believed. But there is much uncertainty, it said, in determining the risk of lung cancer from home exposure.
Miners tend to breathe more rapidly while working than do adults and children in their home environment and are therefore more likely to inhale particles that contain radon, the report points out.
On the other hand, the report adds, household dust particles that contain radon are smaller and are more likely to enter the lungs. More research is needed in these areas, it concludes.
In 1989, the epa recommended that all schools be tested for the gas. The agency estimates that the typical school can be tested for less than $1,000.
Schools with radon levels above 4 picocuries per liter of air, the epa recommends, would need to spend an estimated $3,000 to $15,000 on remediation.--ef