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Living With Radon

EPA’s efforts to save people from radioactivity in their homes have accomplished little

by David J. Hanson
August 22, 2011 | A version of this story appeared in Volume 89, Issue 34

Credit: Newscom
Image of a carbon-canister type radon detector for home use.
Credit: Newscom

The Environmental Protection Agency is preparing another action plan to protect people from the dangers of exposure to radon. The new plan brings together Cabinet departments, such as Agriculture, Energy, Housing & Urban Development, and Defense, to “spur greater action in the marketplace, create jobs in the private sector, and significantly reduce exposure to radon.”

Breathing radioactive radon can undoubtedly cause cancer, but the handling of radon as a public health risk by EPA over the past 25 years has been long on talk but short on results.

Perhaps the most telling fact of EPA’s ineffectiveness is that 25 years ago, the agency claimed that radon exposure was killing up to 20,000 people each year, and today, EPA claims that radon is killing up to 21,000 people per year. So after more than 25 years of action plans, citizen’s guides, awareness programs, and home remediation efforts, the problem is just as bad now as it was then.

The number of U.S. homes and buildings that need to be fixed to reduce radon risk has also changed little over the years. In 1986, EPA estimated that about 8% of buildings may have high radon levels. Today, the agency’s estimate is 7%. Again, 25 years of effort have yielded no appreciable change.

The agency appears to be merely going through the motions of doing something, while simply repeating the data and warnings it used when radon became a public concern in the 1980s. This is not going to inspire a national commitment to reducing radon exposure.

Radon is a naturally occurring gas that comes from the radioactive decay of radium-226 in rocks and soil. It has a history of causing lung cancer in underground uranium miners starting in the 1940s and 1950s, but it was not considered a national health risk until 1984. That’s when Stanley J. Watras, an engineer working at the Limerick nuclear power plant in eastern Pennsylvania, started setting off the plant’s radiation alarm when he entered the plant in the morning. Investigations revealed that the Watras home had an exceptionally high concentration of radon, measured at a whopping 2,700 picocuries per L of air in its basement. This is more than an order of magnitude higher than most miners are exposed to. The resulting media attention led to radon’s being labeled a major public health problem.

On the basis of the information available at that time, EPA set an “action level” concentration for radon in homes and buildings of 4 pCi per L. This is another number that has not changed in 25 years. If your home has radon levels higher than this action level, EPA advises that you do something to reduce the exposure. The agency describes values at or below this level of radon exposure as acceptable.

Scientific organizations, including the U.S. National Academy of Sciences, the World Health Organization, and theInternational Agency for Research on Cancer, put their weight behind the notion that exposure to radon is a major cause of lung cancer. They have backed up EPA on what is a reasonable level of radon exposure.

This acceptable level of radioactivity was controversial when it was set in 1986, although it is not questioned at all today. Basically, EPA and other agencies took the lung cancer data from the highly exposed uranium miners and extrapolated the risk down to the level of home exposure using a linear, no-threshold model of cancer causation.

EPA said then that someone exposed to the 4-pCi level of radon for 70 years would have a 1 to 5% chance of dying of lung cancer. At the time, some experts noted that although this concentration of radon exposure might be prudent from a regulatory angle, there was no empirical evidence that these low levels caused cancer in humans.

Despite having done little over the past decades to gather new data to shore up its case that radon is a major health problem, EPA is now taking more action. According to the agency, the new plan will address current barriers to radon risk reduction, apparently by trying once again to demonstrate to homeowners the importance of radon testing and mitigation and by providing some unspecified incentive to encourage testing. The various government agencies and departments will hold meetings on this plan next year and reveal the new Federal Radon Action Plan next June. EPA contends that these efforts will create demand for thousands of new jobs in the housing sector for radon testing, mitigation, and new construction.

How all of these actions are going to make any impact is unclear. If we have not made any progress in the past 25 years on reducing the amount of cancer caused by radon exposure, or even in the number of houses that need to have radon levels reduced, this latest scheme is unlikely to make any difference. It looks like we will be living with radon a while longer.



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