Flight crews of U.S. airlines are more likely to develop certain types of cancer than the rest of the population according to a study published on June 26, 2018, in the journal Environment Health. The risk may be increased by the number of years spent working onboard.

It was discovered that attendants had a higher frequency of developing various types of cancer such as cervix (1.0% against 0.70%), gastrointestinal cancers (0.47% against 0.27%) and thyroid (0.67% against 0.56%). 3.4% of women flight crews were diagnosed with breast cancer, compared to 2.3% for the rest of the population.

As for male attendants, they were found to have higher rates of skin cancer (1.2% for melanoma and 3.2 for non-melanoma cancer, against 0.69$ and 2.9% for the rest of the adult population). That number is even higher among the male attendants who started working before inflight smoking was banned (most of U.S. domestic flights became smoke-free in 1990 and it extended to all flights in 2000).

Another reason for the higher risk of cancer could be exposure to cosmic ionizing radiation, and the disruption of the 24 hours biological Circadian rhythm because of irregular hours of sleep and crossing of time zones.

The sample of 5366 flight attendants was composed at 80% by women. The average age was 51 years old and average time working as a flight attendant was just above 20 years.

Despite pilots being left out of this specific study, the same results can be expected as they are subject to the same carcinogens.

Irina Mordukhovich, one of the scientists that conducted the study, expects that the first results, highlighting the risks for flight crew, will lead to further studies and protective measures from airlines and manufacturers.