Will frequent air travel expose you to a higher risk of cancer? A new study has shown that it could be the case for flight attendants, and the same factors could affect frequent business travellers too.
Join us and find out more on why frequent flyers maybe at a higher risk of getting cancer.
What is cancer?
Cancer refers to any one of a large number of diseases such as lung cancer with the characteristics of development of abnormal cells that divide uncontrollably and have the ability to infiltrate and destroy normal body tissue. Cancer also often has the ability to spread throughout one’s body.
Cancer is the second-leading cause of death in the world, but survival rates are rising for many types of cancer due to improvements in cancer screening and cancer treatment.
Possible causes for increased cancer rate when flying
Cosmic ionising radiation
Cosmic ionising radiation is more potent at cruising altitudes and is known to be harmful to one’s DNA with prolonged exposure.
UV radiation
Flight crew and frequent flyers are also exposed to UV radiation during flying, which can make them vulnerable to skin cancers.
Apart from cosmic ionising radiation and UV radiation, there are also non-radiation factors that can contribute to an increase in cancer rates when flying.
Circadian rhythm disruptions
As frequent flyers tend to cross time zones, their sleeping patterns will be disrupted. These disruptions can lead to changes in the immune system and cell metabolism, which can potentially weaken the body's ability to suppress tumours.
Chemical exposure
Chemical contaminants found in the cabin, such as engine leakages and flame retardants contain compound that can act as hormone disruptors and increase the risk of some cancers.
Life style habits
Lifestyle habits also play an important role as cabin crew tend to fly over the world which means they will also spend more time in tropical places which can increase their exposure to UV radiation.
Studies done regarding flight crew and cancer rates
A new study has shown that both female and male cabin crew for US based airlines have higher rates of many types of cancers as compared with the general population. This includes cancers of the breast, cervix, skin, thyroid and uterus, as well as gastrointestinal system cancers which includes the colon and stomach etc.
One possible explanation for these increased rates is that cabin crew are exposed to a lot of known and potential carcinogens or cancer-causing agents within their work environment according to a study done by Harvard University’s T.H. Chan School of public health.
One of these carcinogens is cosmic ionising radiation, which is elevated at higher altitudes. Cosmic ionising radiation is particularly damaging to one’s DNA and is a known cause of breast cancer and non-melanoma skin cancer. As compared to the population of all US workers, cabin crew receive the highest yearly dose of ionising radiation on the job.
In the new study, researchers look at data from more than 5,300 cabin crew from different airlines who completed an online survey as part of the Harvard Flight Attendant Health study. The analysis looked at the cancer rates in these flight attendants compared to a group of about 2700 people who had a similar income and educational status but were not cabin crew.
The results of the survey found that in female cabin crew, the rates of breast cancer were about 50 percent higher than women from the general population.
Additionally, melanoma rates were more than two times higher and non-melanoma skin cancer rates were about four times higher in female cabin crew compared with women from the general population. These elevated cancer rates were observed despite indications of good health behaviours such as low levels of smoking and obesity, in the cabin crew group as a whole. However, studies also has shown that this could be due to the amount of sun-tanning flight crew do when visiting tropical places.
Are frequent flyers really more prone to cancer?
It is not surprising to know that one is exposed to radiation when flying. It is also true that long-term radiation exposure can lead to cancer. But does flying frequently actually increase one’s risk of cancer? The answer is: It's complicated.
While some studies have shown that flight crew and frequent fliers have an increased risk of some cancers, in reality, the research is mixed. One can’t randomly assign research subjects to different doses of radiation to see what happens, so scientists will have to first take a look at who is already exposed to radiation because of their job or circumstances, and then see whether if that group holds higher cancer rates than the rest of the general population.
The problem with doing this as according to a staff scientist in the radiation epidemiology branch of the national cancer institute, is that any increases in cancer rates may reflect differences in lifestyle factors such as smoking or increased sun exposure which may not necessarily result from radiation exposure. Although radiation from flights is a contributing factor towards increased cancer rates, it might not be the best indication to whether frequent fliers are more prone to cancer.
Although there are many studies relating frequent flying to an increased rate of cancer, the results are not conclusive and consistent as there are also many other underlying factors that contribute to one’s risk of getting cancer. Therefore, it is still difficult to determine whether frequent flying is the main or sole reason towards the increase in cancer rate from frequent flying.
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