Flight attendants and pilots face the highest risk of dying from radiation-related cancers — surpassing even those who work directly with radioactive materials, according to a new study.
Cosmic radiation originates in space. While only a small amount reaches the Earth’s surface, exposure increases significantly at high cruising altitudes.
Though earlier small-scale studies suggested a link between frequent flying and higher cancer mortality among aircrews, new research published in JAMA Internal Medicine provides definitive evidence. The study analysed national data from over 12 million death certificates containing occupational details, tracking mortality from radiation-linked malignancies including leukaemia, lymphoma, multiple myeloma, and cancers of the skin, breast, thyroid, prostate, and central nervous system.
Out of more than 500 professions, flight attendants registered the highest percentage of deaths from radiation-related cancers, with pilots ranking second. For both jobs, the odds of dying from every specific radiation-related cancer were disproportionately elevated.
Crucially, neither group showed higher-than-normal death rates from non-radiation-linked cancers. Australian radiation experts Catherine Olsen and Ken Karipidis noted in an accompanying commentary that this distinction supports the hypothesis that workplace radiation exposure—rather than lifestyle or socioeconomic factors—drives the excess mortality.
Researchers found flight attendants had roughly 50% higher odds of dying from a radiation-related cancer than the general working population, while pilots faced 36% higher odds.
In terms of absolute risk, about 6.9% of flight attendant deaths (roughly 1 in 14) and 6.7% of pilot deaths were caused by these cancers, compared to 5% in the general workforce, noted lead author Dr Vishal Patel of Harvard Medical School.
The authors acknowledged study limitations. They lacked exact exposure metrics for individual crew members and noted potential occupation misclassification on death certificates. Furthermore, they could not isolate the impact of circadian rhythm disruptions caused by jet lag, time-zone crossings, and irregular schedules, which can exacerbate cancer risks.
Despite the Federal Aviation Administration acknowledging that aircrews encounter ionising radiation, the US government sets no federal dose limits and requires no active monitoring. "You can’t manage an exposure you’ve decided not to measure," Patel stated.
Sara Nelson, president of the Association of Flight Attendants-CWA representing 55,000 workers, said the findings reinforce long-standing union demands for official oversight. "The risk is known, but crew are not educated or informed. And no one is taking responsibility," Nelson said.
Commentators Olsen and Karipidis suggested that annual skin checks and earlier or more frequent mammograms may be warranted for high-altitude aircrews. They added that physicians treating pilots and flight attendants should maintain a heightened index of suspicion for cancer during routine medical evaluations.