New research published in JAMA Internal Medicine points to a notable occupational pattern in aviation: pilots and flight attendants recorded the highest and second-highest shares of deaths linked to cancers associated with radiation among more than 500 U.S. jobs.
The study examined over 12.7 million U.S. death records from 2020 to 2024 and matched them with usual occupations listed on death certificates. After adjusting for age, sex, race, ethnicity, education and marital status, researchers found that 6.9% of flight attendant deaths and 6.7% of pilot deaths were tied to radiation-related cancers.
The cancers most often involved included breast, prostate, leukemia, lymphoma, melanoma, thyroid cancer, multiple myeloma and cancers of the central nervous system. The pattern was not seen in cancers unrelated to radiation, and ground-based aircraft workers did not show the same trend.
Why altitude matters
At cruising height, aircraft are shielded by less atmosphere, which means crews are exposed to more cosmic ionizing radiation than people on the ground. The CDC notes that this exposure increases on long-haul and high-latitude routes. For occasional passengers, the dose remains low, but for aircrew it can build up over years of work.
Researchers estimate that pilots and flight attendants may receive about 3 to 6 millisieverts annually depending on route patterns, while a frequent traveler taking 10 cross-country round trips a year would absorb far less.
The study also found elevated mortality from breast, prostate and central nervous system cancers, along with melanoma. Pilots additionally showed higher leukemia mortality. At the same time, the authors note that other factors in aviation -- including cockpit ultraviolet exposure and irregular sleep schedules -- may also play a role.
Earlier studies have pointed in a similar direction, including research on flight attendants and meta-analyses of pilots and cabin crew. What makes this analysis stand out is its scale and its use of nationwide mortality data across hundreds of occupations.
Even so, the findings are observational and do not prove direct causation. The authors argue that the results strengthen the case for more consistent radiation monitoring and protection standards for aircrew. As aviation grows more connected and long-range, better exposure tracking could help shape safer skies for the future.
