Update to EPA Radiogenic Cancer Risk Estimates

In April 2011, EPA completed a revision of its 1994 report, "Estimating Radiogenic Cancer Risks." The revised document presents new estimates of cancer incidence and mortality risks due to low doses of ionizing radiation for the U.S. population, as well as their scientific basis.The 1994 report provided the basis for Federal Guidance Report No. 13,"Cancer Risk Coefficients for Environmental Exposure to Radionuclides."The updated report will be used to support revision to FGR-13 and earlier reports compiling dose coefficients for internal and external exposure to radionuclides. It is anticipated that these documents will be widely considered in developing regulatory standards and cleanup goals, including those for EPA's Superfund program.

For the most part, the revised estimates of radiogenic risk are calculated using models recommended by the National Academy of Sciences2006 report on "Health Risks from Exposure to Low Levels of Ionizing Radiation," commonly known as BEIR VII (Biological Effects of Ionizing Radiation). As in BEIR VII, the EPA report provides models for estimating risk as a function of age at exposure, age at risk, gender,and cancer site. A number of extensions and modifications to the BEIR VII approach have been implemented, including extension of risk estimates to high-LET (Linear Energy Transfer) radiation, an expanded analysis of uncertainties, and use of a stationary U.S. population to facilitate estimates of lifetime risk. The final report also reflects recommendations from an independent review by EPA's Science Advisory Board.