The U.S. Million Person Study of Low-Dose-Rate Health Effects

From Nuclear Newswire (June 27, 2025)

There is a critical knowledge gap regarding the health consequences of exposure to radiation received gradually over time. While there is a plethora of studies on the risks of adverse outcomes from both acute and high-dose exposures, including the landmark study of atomic bomb survivors, these are not characteristic of the chronic exposure to low-dose radiation encountered in occupational and public settings. In addition, smaller cohorts have limited numbers leading to reduced statistical power.

The Million Person Study of Low-Dose-Rate Health Effects (MPS) is one of the largest radiation occupational studies designed specifically to provide understanding of late health effects from chronic radiation exposures. It has been ongoing for 20 years and includes only U.S. workers and veterans, within 30 epidemiologic subcohorts. The MPS has published more than 100 articles to date in the peer-reviewed scientific literature and is implemented by a team of radiation scientists using consistent epidemiologic methods while following precise dosimetry guidelines for determining organ-specific radiation doses from low-LET (linear energy transfer) external radiation, neutrons, and intakes of radionuclides. 

To read the entire article, visit Nuclear Newswire’s website. Learn more about ORISE’s specific role in the Million Person Study, including which ORISE staff members have co-authored published research supporting the long-term study.