An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Radiation Protection

Blue Book: EPA Radiogenic Cancer Risk Models and Projections for the U.S. Population

EPA Radiogenic Cancer Risk Models and Projections for the U.S. Population, also known as the Blue Book, is a revision of EPA's methodology for estimating cancer risks from radiationHelpradiationEnergy given off as either particles or rays. exposure.

These updates are based on the National Research Council's 2006 report "Biological Effects of Ionizing Radiation (BEIR VII)," as well as on other updated science.

On this page:


The Blue Book calculates cancer risk estimates separately by age at exposure, sex and potentially affected organ. Its risk estimate methodology reflects the scientific consensus of the BEIR VII committee. The Blue Book presents new EPA cancer incidence and mortality risk coefficients for the U.S. population from exposure to low doses of ionizing radiationHelpionizing radiationRadiation with so much energy it can knock electrons out of atoms. Ionizing radiation can affect the atoms in living things, so it poses a health risk by damaging tissue and DNA in genes.. The document also presents the scientific basis for the estimates.

Blue Book Cover

The document takes into account recommendations made by EPA's Science Advisory Board (SAB), which completed its review in January 2010. The SAB relied on advice from its Radiation Advisory Committee panel of non-EPA scientists chosen for their objectivity, integrity and expertise in radiation science and protection.

The Blue Book has undergone an extensive peer review process, which included opportunities for the public and stakeholders to provide comment.


As in BEIR VII, the models in the Blue Book describe how radiogenic cancer risks depend on such factors as:

  • Age of exposure.
  • Age at which person might get cancer.
  • Sex.
  • Type of cancer.

However, a number of extensions and modifications to the BEIR VII models have been implemented:

  • Risk estimates for alpha particles.
  • Risk estimates for basal cell carcinomas, kidney cancer, bone sarcomas and cancers from prenatal exposures.
  • More extensive analysis of uncertainties associated with the radiogenic risk estimates.

A large body of epidemiological and radiobiological data support the risk models. In general, results from these data are consistent with a linear no-threshold (LNTHelpLNTThe assumption that the risk of cancer increases linearly as radiation dose increases. This means, for example, that doubling the dose doubles the risk and that even a small dose could result in a correspondingly small risk. Using current science, it is impossible to know what the actual risks are at very small doses.) dose response model in which the risk of inducing a cancer in tissue irradiated by low doses of radiation is proportional to the dose received.

Top of Page

What's Next

EPA will use the scientific information on radiation risks provided in the Blue Book, together with information from other sources, when considering potential modifications and updates to radiation protection rules and guidance.

One of the documents that will be updated based on the new science in the Blue Book is Federal Guidance Report No. 13 - Cancer Risk Coefficients for Environmental Exposure to Radionuclides (FGR-13). FGR-13 provides methods and data for estimating risks due to both internal and external radionuclideHelpradionuclideRadioactive forms of elements are called radionuclides. Radium-226, Cesium-137, and Strontium-90 are examples of radionuclides. exposures. It includes coefficients for assessing cancer risks from environmental exposure from about 800 radionuclides. It is anticipated to take at least two to three years to complete this revision.

The update to FGR-13 will allow us to confirm or adjust estimates of health effects related to EPA's rulemaking activities and make updates based on those findings.

Top of Page

Get a Copy

EPA established a docket for the release of the Blue Book. View Docket ID No. EPA-HQ-OAR-2011-0436 on When making regulatory decisions, EPA and other federal agencies use dockets to make documents publicly accessible.

Electronic Version

Download EPA Radiogenic Cancer Risk Models and Projections for the U.S. Population.

Download Blue Book materials in EPA Docket ID No. EPA-HQ-OAR-2011-0436 on

Hard Copies

  • To request a hard copy of the Blue Book, please e-mail
  • There are also several options for reviewing or obtaining copies of docket materials:

Blue Book Docket Location

Official EPA Air and Radiation Docket
Docket and Location
Hours of Operation Contact

Reading Room:

Air and Radiation Docket and Information Center
Room 3334, U.S. Environmental Protection Agency
1301 Constitution Avenue, NW
Washington, DC 20460-0001

Mailing Address:

Air and Radiation Docket
EPA Docket Center (EPA/DC)
Mail Code 2822T
1200 Pennsylvania Ave., N.W.
Washington, DC 20460

8:30 am - 4:30 PM

(except federal holidays)

Phone: (202) 566-1742
Fax: (202) 566-9744

EPA Docket Clerk

As provided in EPA's regulations at 40 CFR Part 2, and in accordance with normal EPA docket procedures, if copies of any docket materials are requested, a reasonable fee may be charged for photocopying.

Top of Page