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June 6, 2001
Radon in water lesser health risk
by Jane Roseland, Springfield MonitorThough the radioactive gas radon may be found in water supplies, health and water officials say radon in water poses less of a health risk than radon found in the air.
"Relatively small amounts of radon exposure comes from water," said Joel Christensen, manager of Water Operations for the Metropolitan Utilities District in Omaha.
Both Christensen and material from the U.S. Environmental Protection Agency (EPA) said that compared to radon entering the home through soil, radon entering the home through water -- in most cases -- poses a smaller risk of exposure.
The biggest risk from radon in water is when the radon is released from the water in to the air, which can contribute to the total radon level in the home, according to Sharon Skipton, University of Nebraska Extension educator.
Radon gas also can enter the home through well water and can be released into the air you breathe when water is used for showering and other activities, she said.
Skipton said that for every 10,000 picocuries per liter (pCi/L) of radio in the water, there would be an increase of 1 pCi/L in the air. The EPA has set a "recommended action level" of four pCi/L of radon in the air. Homes above that level should be mitigated to reduce radon, Skipton said.
Christensen said M.U.D., which serves customers in Omaha, Bellevue, LaVista, Ralston and other communities, has done some spot testing for radon at its water treatment facilities in the past few years.
District material shows that the highest level of radon recorded was 240 pCi/L found at the the Platte River Water Treatment Plant southeast of Omaha.
The EPA estimates that radon in the air causes about 14,000 lung cancer deaths per year in the United States. The U.S. Surgeon General warns that radon is the second leading cause of lung cancer in the U.S., second only to smoking.
The National Academy of Sciences (NAS), in a report released September 15, 1998, estimates that 160 lung cancer deaths from radon in water occur each year in the U.S., and less than one death per year (0.92) in Nebraska. These deaths, the NAS said, are the result of inhaling radon released into the air from a waterborne source within the home.
Recognizing that, the EPA is expected to set a new standard for radon levels in drinking at 300 pCi/L. The EPA's regulations would allow states to regulate radon levels in the water in one of two ways: States could either adopt the standard as the maximum state standard for radon levels in drinking water or states could set an alternate maximum standard of no higher than 4,000 pCi/L if those states create a multimedia mitigation program that would include radon education, testing, training and incentive programs.
In April, the Nebraska Legislature passed a bill relating to radon levels in drinking water. Legislative Bill 668, sponsored by Aurora Senator Bob Kremer, and passed by the Legislature, 45-0, enacts the latter option, and allows the Nebraska Department of Health and Human Services Regulation and Licensure to establish an alternate maximum level for radon in drinking water and a multimedia mitigation program.
Senator Kremer said that raising the alternate maximum level for radon in drinking water would save small towns a lot of money. If the water systems in Nebraska's small towns (serving less than 500 people) were to treat their drinking water for removal of radon, an excessive financial burden would be placed on those systems, Kremer said.
The Nebraska Section of the American Water Works Association said the estimate to install a radon treatment facility would cost these small towns an average of $750,000 each.
Radon can be removed from water from each household, according to the EPA. Point-of-entry treatment is the most effective treatment to remove radon before it enters the home. Point-of-use treatments, such as those at the water faucet, are not as effective, and officials discourage this treatment because it isn't effective in removing the radon risk in water.
Skipton said testing for radon in water should be left to professionals because of the equipment involved, whereas testing for radon n the air can be done by homeowners who purchase a test kit for $10-$30 at most hardware stores.
She recommends residents test the air in their homes before testing the water. Radon mitigation companies can assist homeowners who wish to test their water for radon.