A landmark decision in South Korea established that the death from gastric cancer of a male flight attendant was akin to an industrial accident caused by cosmic radiation exposure. The state-run Korea Workers’ Compensation and Welfare Service (K‑COMWEL)¹ issued a ruling in October 2023² which suggests that a flight attendant’s chronic exposure to cosmic radiation may pose more serious health threats than previously recognized.

Cosmic radiation, which originates in outer space from solar activity and galactic sources, is composed of penetrating particulate and electromagnetic ionizing radiation. It consists of high-energy charged particles, x‑rays, and gamma rays produced in space. Cosmic ionizing radiation is a known human carcinogen and a causal risk factor for non-melanoma skin cancer and cancers of the breast, salivary gland, esophagus, stomach, colon, lung, bone, kidney, urinary bladder, brain/central nervous system, and thyroid.³

Given their accumulated exposure from extended periods of time spent at higher flight altitudes, where the shielding effect of the earth’s atmosphere is decreased, aircrew are exposed to higher quantities of naturally occurring cosmic radiation than the general population. According to various studies, flight altitude, distance of the route from the North and South Poles, and flight hours are all important factors affecting the amount of radiation absorbed by aircrew.⁴

In particular, the atmosphere at the North and South Poles is thinner than at the equator, which results in reduced atmospheric barriers on routes closer to these polar regions such as North America route, flying over the Arctic Circle. Accordingly, the higher the flight altitude, the higher the human absorption of cosmic radiation.

The flight attendant in this ruling, identified as Mr. Song, was diagnosed with stage four gastric cancer in April 2021 and died the following month, at the age of 53. Mr. Song reportedly started working with Korean Air in 1995 and as of 2021 was flying an average of 1,022 hours annually, half of which were on long-haul flights to and from the Americas and Europe. These flights all passed through the Arctic Circle, a zone noted to be notorious for its high cosmic radiation levels due to the earth’s magnetic fields.⁵

Korean Air denied that there was any correlation between Mr. Song’s cancer and cosmic radiation; Korean Air says it had ensured its flights attendants’ cumulative radiation exposure remained below the safety standard of 6mSv per annum. This argument was rejected by the K‑COMWEL panel, who considered that it was possible Mr. Song had been exposed to more than 100mSv per annum of accumulated radiation given that the measuring method deployed by Korean Air could have downplayed the actual amount of his cumulative radiation dose.⁶

The K‑COMWEL ruling is significant as it:

• accepts the causal link between solid cancers such as gastric cancer and cosmic radiation,
• is the first time an official labour body in South Korea has recognized the correlation between cosmic radiation and cancer for flight attendants as an industrial death, and
• has potentially broader implications for the airline industry in its emphasis on the importance of implementing preventive measures to safeguard the health and safety of aviation professionals.

In South Korea, industrial accident compensation insurance is a statutory insurance designed to guarantee the income of an injured worker and his/her family. Under the Labour Standards Act, the state collects insurance premiums from employers from which it then administers the payment of compensation to injured workers on the employers’ behalf. The coverage now includes new industrial disease, work-related exhaustion, and stress.

Given the international scope and nature of the aviation profession, this ruling could have precedent use in other countries’ workers’ compensation regimes to argue and/or provide the necessary medical causal link between the development of certain cancers and the environmental exposures from the injured person’s in‑flight workplace duties.

Whilst an awareness of the link between cosmic radiation and various types of cancers is a relatively recent medical development, cosmic radiation is an emerging insurance risk to monitor. Although the relatively contained “in‑air” workforce numbers may operate to limit an avalanche of cosmic radiation claims, one only needs to look at other prolonged exposure examples in history, like asbestos and mesothelioma and, more recently, engineered stone and silicosis, to recognize the potentially significant impact of such a ruling on future personal injury claims and actions.

There is potential for such causal findings to expand beyond the industrial death/workers’ compensation arena into other insurance products and lines of business such as aviation liability, public and products liability, and to capture non-employee frequent flyer claimants in the years to come as science, medicine, and litigation trends emerge and converge.