National Academies steers low-dose radiation research in a new direction

The American Nuclear Society has supported just such a move since a low-dose radiation research program within the DOE Office of Science was defunded and later terminated in 2016. In response to input from ANS and other stakeholders, Congress reauthorized DOE low-dose radiation research in the bipartisan Energy Act of 2020. The Consolidated Appropriations Act of 2021 boosted program funding to $20 million and tasked the National Academies with developing a strategic plan and assembling a committee to make recommendations for research to be carried out by the Office of Science in cooperation with other federal agencies. The National Academies has just released the objectives of the consensus study it will conduct to develop a long-term strategy for the program.

Asking the right questions: All research on low-dose radiation health effects must grapple with the inherent complexity of epidemiology and the human body. The National Cancer Institute estimates that about 39.5 percent of adults in the United States are likely to be diagnosed with cancer during their lifetime. People are exposed to many cancer risk factors, including stress, genetics, health, and occupation, and the most rigorous attempts to ascertain whether low doses of ionizing radiation can increase cancer risk have necessarily been inconclusive.

“This is an issue that has been around as long as nuclear technology,” said Craig Piercy, ANS executive director and chief executive officer. “There is a lack of understanding of what happens at very low doses, and for so many years the narrative has been the same. The question was always, what is safe? A better question—the one being asked now—is, how do we communicate what we understand about radiation? We’ve tried to shift the debate to focus on real-life problems, deriving practical information to drive better decision-making.”

Central to current radiation protection regulations is the linear no-threshold (LNT) model, which assumes that radiation harm increases linearly with exposure and that zero harm exists only at zero exposure. The LNT model may result in overestimates of risk from low levels of radiation, which means that resources expended to meet LNT-based standards may yield little or no benefit. Decision-makers have repeatedly deferred decisions to replace the LNT model and instead have called for more research. ANS has recommended research focused on enhancing the scientific and public understanding of the actual risks associated with radiation.

“As part of a group that includes the Clean Air Task Force, the Health Physics Society, Oak Ridge Associated Universities, and ClearPath, ANS led a persistent two-year effort to get congressional authorizing language included in the Energy Act of 2020,” said John Starkey, ANS public policy director. “Part of this plan captures the suggestions ANS gave to the Department of Energy and the National Academies last year. Over the next 12 months, as the DOE’s Office of Science stands up the program, ANS will continue to offer its support.”

A risk-informed approach: The legislation that authorized the new program calls for improved risk-assessment and risk-management methods. A risk-informed approach to low-dose radiation would likely take into account the fact that Americans receive a radiation dose of about 620 millirem each year (about half from natural background radiation and half from man-made sources). Annual doses from activities such as having an X-ray or taking a coast-to-coast flight can easily exceed current environmental dose standards, and since frequent flyers aren’t subject to dose limits, regulating the same dose in a different context is, arguably, inconsistent.

The new research program could potentially lead to the adoption of new standards and new ways to communicate about low-dose radiation, even if the LNT model is not replaced. The strategic plan developed by the National Academies specifically calls for the program to “support education and outreach activities to disseminate information and promote public understanding of low-dose radiation” and to “identify and, to the extent possible, quantify, potential monetary and health-related impacts to federal agencies, the general public, industry, research communities, and other users of information produced by such research program.”

The DOE is undertaking a long-term program that will require sustained funding through annual congressional appropriations. ANS will continue to support funding to meet these goals.

“That’s a role the ANS community is positioned to play,” Piercy said. "We’re focused on the long term, on science in service of a goal. We recognize that the long-term health of nuclear is dependent on the public’s ability to understand it.”