Flight crews face higher radiation cancer risks than radiology professionals

Flight crews face a higher risk of radiation-linked cancers than professionals in nuclear medicine or radiology, according to an analysis published in JAMA Internal Medicine. While overall cancer rates for aviation personnel do not exceed the general professional median, there is a significant increase in specific malignancies associated with ionizing radiation.

Radiation Sources at High Altitude

The primary hazard for pilots and flight attendants is cosmic radiation. On Earth's surface, the atmosphere acts as a shield, absorbing high-energy particles from space. As an aircraft climbs, this protection thins. The intensity of exposure also varies by geography: radiation levels are higher near the poles than at the equator.

Unlike patients receiving occasional diagnostic imaging, flight crews are exposed to ionizing radiation chronically throughout their careers.

Study Design and Findings

Researchers from Harvard Medical School, led by Vishal Patel, analyzed 12.7 million death certificates from the U.S. National Vital Statistics System for the period 2020–2024. The study examined 503 professions, categorizing deaths into two groups: cancers potentially linked to radiation (including leukemia, melanoma, and cancers of the breast, thyroid, and prostate) and other types of oncology.

The analysis found that aviation personnel in the U.S. receive the highest average annual effective dose of radiation among all professional groups. While a typical passenger completing 10 round-trip flights receives approximately 0.4 millisieverts, pilots and flight attendants are exposed to 3–6 millisieverts annually.

The risk increase for radiation-dependent cancers was as follows:

Contributing Factors and Mitigation

Beyond cosmic rays, experts identify ultraviolet (UV) light—particularly in cockpits—and disrupted circadian rhythms due to shift work as additional risk factors. UV exposure through aircraft windows is noted as a specific contributor to melanoma risk.

To manage these threats, the researchers suggest implementing regular medical screenings tailored to flight seniority and considering federal limits on cumulative radiation doses. Radiologists, by contrast, operate in controlled environments with protective shielding and strict dosimetric monitoring, which accounts for their lower relative risk.

Clinical pharmacologist Aleksey Ryabtsev notes that any systematic radiation load requires strict control, as the biological effect of cumulative ionizing doses lacks a definitive "safe" threshold over the long term. Therapist Anna Kuznetsova emphasizes that aviation health checks should include specific oncological screenings to detect pathologies before clinical symptoms appear.

Important: This article is for general information and does not replace medical advice. Do not start, stop, or change treatment without a qualified clinician.

Source: This article was adapted from an original Russian-language publication by Pravda.Ru.