Flight attendants may face higher-than-average risks of breast and skin cancers, although the reasons why are not yet quite clear. This was the findings of a study that a group of researchers made in the U.S.
Harvard researchers found that compared with women in the general U.S population, female flight attendants had a 51 percent higher rate of breast cancer. Meanwhile, their rates of melanoma and non-melanoma skin cancers were about two to four times higher, respectively. What is still unclear is why this pattern is being seen, and because it was just an observational study, it could not prove the cause and effect.
“Flight crews have a number of exposures that could potentially play a role,” said McNeely, an instructor in environmental health at the Harvard School of Public Health who was part of the research team. “But no one knows for sure whether cosmic radiation is to blame for flight attendants’ higher cancer risks,” McNeely added.
Aircrews can also come in contact with a number of chemicals, she noted. And before smoking bans went into effect, they were habitually breathing secondhand smoke. McNeely also said that flight crews deal with constant time-zone changes and irregular sleep schedules, which means many disruptions to the body’s circadian rhythm, or “internal clock” and circadian disruptions from shift work have been linked to increased risks of obesity and diseases like diabetes and heart disease.
“It’s hard to tease out which of those factors might be more important than others, or whether it’s a combination of all of them,” McNeely said.
“For example, they may have more UV [sun] exposure because of their opportunity to travel,” said Boffetta, who was not involved in the study. In addition, he said, women on aircrews may put off having children or have fewer kids, compared with other women and reproductive factors like that are associated with the risk of breast cancer.
Still, McNeely said, her team found some evidence that the longer flight attendants had been on the job, the higher their cancer risk was. Among women, the risk of non-melanoma skin cancer rose in tandem with job tenure.
Male flight attendants had higher rates of skin cancers than other men. But the differences were not significant in statistical terms. According to McNeely, the findings will “not be news” to aircrews because they’ve long been aware their occupation may be linked to increased cancer risks.
Boffetta said that regardless of the reasons, the higher rates of skin and breast cancers among flight attendants underscore an important point: They should get recommended cancer screenings.
McNeely noted that the European Union has already taken a step requiring that aircrews be monitored for their radiation exposure. If it reaches a certain level, their work schedules are adjusted.
The potential risks to flight crews bring up another question: What about passengers who fly frequently?
McNeely said it’s not clear whether they face any health risks. “We study workers first, because they have the greatest exposures,” she noted.