By Maya Brownstein

BOSTON, Mass. — U.S. counties located closer to operational nuclear power plants (NPPs) have higher rates of cancer mortality than those located farther away, according to a new study led by the Harvard T.H. Chan School of Public Health.

The study is the first of the 21st century to analyze proximity to NPPs and cancer mortality across all NPPs and every U.S. county. The researchers emphasized that the findings are not enough to establish causality but do highlight the need for further research into nuclear power’s health impacts.

The study was published Feb. 23, 2026, in the journal Nature Communications.

Numerous studies on the potential link between NPPs and cancer have been conducted around the world, with conflicting results. In the U.S., these studies have been rare and limited in their scope, focused on a single NPP and its surrounding community.

To expand the evidence base, the researchers conducted a national assessment of NPPs and cancer mortality between 2000 and 2018 using “continuous proximity.” They used advanced statistical modeling that captured the cumulative impact of all nearby NPPs, rather than just one. The locations and dates of operation of U.S. NPPs — as well as some nearby in Canada — were obtained from the U.S. Energy Information Administration, and county-level data on cancer mortality was obtained from the Centers for Disease Control and Prevention. The researchers controlled for potential confounders [that might effect data] in each county, including educational attainment, median household income, racial composition, average temperature and relative humidity, smoking prevalence, BMI [body mass index], and proximity to the nearest hospital.

The study found that U.S. counties located closer to nuclear power plants experienced higher cancer mortality rates, even after accounting for socioeconomic, environmental, and health care factors. The researchers estimated that over the course of the study period, roughly 115,000 cancer deaths across the U.S. (or about 6,400 deaths per year) were attributable to proximity to NPPs. The association was strongest among older adults.

“Our study suggests that living near a NPP may carry a measurable cancer risk — one that lessens with distance,” said senior author Petros Koutrakis, Professor of Environmental Health and Human Habitation. “We recommend that more studies be done that address the issue of NPPs and health impacts, particularly at a time when nuclear power is being promoted as a clean solution to climate change.”

The researchers noted that the results are consistent with the results of a similar study they conducted in Massachusetts, which identified elevated cancer incidence among populations living closer to NPPs.

They also noted some limitations to the study, including that it did not incorporate direct radiation measurements and instead assumed equal impact by [emissions from] all NPPs.

— Maya Brownstein is the Media Relations Manager in the Office of Communications, Chan School of Public Health.

— Link to Harvard report is here: https://www.nature.com/articles/s41467-026-69285-4

The Canadian Coalition for Nuclear Responsibility (CCNR) has formally criticized the Canadian Nuclear Safety Commission regarding the inadequacy of its “Regulatory Oversight Report on Nuclear Power Generating Sites” for the year 2024.

CCNR’s President, Gordon Edwards, Ph.D., drafted the group’s critical submission to the Safety Commission, titled “Overlooking Offsite Impacts.”

The CCNR’s “intervention” includes a list of six proposed improvements that speak not just to Canada’s reactor operations, but to regulatory agencies everywhere that oversee permitted or accidental releases of radioactive materials to the air and water. Routine emissions of radioactive pollution from nuclear generating stations are permitted because governments have been convinced by nuclear power promoters that their pollution is not overly dangerous. Nuclear reactors cannot operate without releasing large volumes of contaminated water and gases, the venting of which helps to control the temperature, pressure, and coolant volume in operating systems.

We are sharing the paper’s six major recommendations ⸺ which follow ⸺ because they apply equally well to industry proposals and regulatory agencies anywhere in the world that are considering new nuclear reactor construction.

  Canadian Coalition for Nuclear Responsibility recommends:

* The Canadian Nuclear Safety Commission (CNSC), as an agency legally bound to disseminate objective scientific information to the public, should publicly set the record straight by saying quite simply that nuclear power is not altogether clean. Alternatively, CNSC should either cease describing itself as a science-based organization, or issue a clear science-based explanation of how one may logically reconcile large routine emissions of radioactive poisons into the environment with the notion of nuclear power as ‘clean energy’;

* The CNSC should require its nuclear generating station licensees to post on the internet real-time data on radioactive emissions from the plant as they occur, and to give advance warning when elevated emissions are likely to result from planned outages or other planned activities such as overnight tritium purges;

* The CNSC should require its nuclear generating station licensees to calculate the collective dose to the population within five miles of the plant, based on annual emissions;

* The CNSC should require its nuclear generating station licensees to work to reduce their annual environmental emissions of tritium, carbon-14, iodine-131, and particulates of alpha-emitting and beta-emitting radionuclides by several orders of magnitude;

*The CNSC should immediately adopt a provisional Relative Biological Effectiveness (RBE) of ‘2’ for tritium exposures, with the expectation that the RBE for tritium may be revised upwards as new evidence becomes available; and

* The CNSC should publish a science-based explanation and justification of the existing Canadian standard for the maximum permissible concentration of tritium in drinking water….

⸺ To read CCNR’s full written intervention, see: www.ccnr.org/CCNR_ROR_Report_2026.pdf