Reducing Radon State by State.
In August 2000, the U.S. Environmental Protection Agency (EPA) expects to finalize proposed regulations to protect people from exposure to radon through indoor air and drinking water. The regulations will provide flexibility in determining how to limit exposure to radon by allowing each state to focus its reduction efforts as it sees fit. Research suggests that 6% of U.S. homes contain more radon than the current EPA recommendation of 4 picocuries per liter (pCi/L). Radon from drinking water accounts for an estimated 2% of exposure. The framework for this proposal was initiated in the Safe Drinking Water Act Amendments of 1996. The act directed the EPA to finalize standards for radon contamination, to be accompanied by a multimedia mitigation (MMM) program, which states may enact in one of two ways. The first option calls for state programs requiring individual water systems to meet a less stringent proposed alternative maximum contaminant level of 4,000 pCi/L. States would also be expected to develop MMM programs to reduce radon in indoor air. At a cost of nearly $86 million dollars per year, the EPA says this is the most cost-effective radon risk reduction approach and the one it expects most states to adopt. If a state does not choose this first option, then individual water systems must either comply with a tighter proposed maximum contaminant level of 300 pCi/L in drinking water or conform to the 4,000 pCi/L standard and develop a state-approved MMM program plan to reduce indoor radon. The proposed regulation does not set safety standards for airborne radon concentrations, but the EPA still recommends that households reduce indoor radon levels to a maximum of 4 pCi/L. Under the proposed regulation, water companies would be required to begin quarterly monitoring for radon within three years after the final rule is published. Companies that agree to develop MMM programs would not have to begin the required monitoring until February 2005. In most cases, radon is released to indoor air from the soil underneath homes and buildings as a by-product of the breakdown of uranium. A naturally occurring gas, radon is a human lung carcinogen contributing to about 20,000 lung cancer deaths every year in the United States, according to a 1999 report by the National Academy of Sciences on radon in indoor air. The U.S. Surgeon General has warned that radon is the second leading cause of lung cancer. If someone living in a house with high radon concentrations smokes, there is an even greater risk for household members to develop cancer. Although a smaller source of radon, drinking water also presents the risk of stomach cancer. The EPA estimates that drinking water containing radon causes 168 cancer deaths per year, 11% of which are due to stomach cancer. |