For the fifth year in a row I flew approximately 60 times. Most of my flights are within Europe, so an average flight is quite short (~1000 km, ~2 hours). I am concerned about negative health effects caused by cosmic ray radiation.

The calculator on the Federal Aviation Administration website suggests that I receive ~7-9 µSv per 2 hour flight. This means adding additional ~0.5 mSv to my annual radiation dose. Background radiation in my area of 1 mSv/year and a few medical x-rays can easily add up to 3-4 mSv annual dose.

According to BSS/EU, the safe yearly radiation exposure for the general public is 1 mSv.

An example of one of my flights:

One of my short flights

  1. Do my calculations make sense?
  2. Should I be concerned about increased cancer risk? Are there any possible negative health effects not related to radiation?
  3. What are some articles/papers on the topic that you'd recommend?
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    Pilots should be suffering unprecedented levels of cancer then, no? – Augustine of Hippo Sep 8 '18 at 11:41
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    0.5 mSv is not statistically significant. There is no evidence that such a small increase in radiation contributes to an increase in cancer incidence. Your health concerns from sixty segments a year should arise from other concerns (poor quality food and poor quality sleep being the main two serious hazards). – Calchas Sep 8 '18 at 12:44
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    @MusoniusRufus: It seems that airline pilots do indeed suffer higher levels of cancer than average, although the reason is not clear. Long-haul pilots seem to be at the greatest risk; flights within Europe are relatively safe. – TonyK Sep 8 '18 at 17:37
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    Is radiation truly the only concern? Flying is physically tiring and I guess that's where the real harm is. – JonathanReez Sep 8 '18 at 20:06
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    You may find this chart informative: xkcd.com/radiation – Jamie Hanrahan Sep 8 '18 at 23:41
  • It is usually not correct to talk about factors causing cancer. Factors increase the probability of getting cancer. The human mind does not deal well with very small and very large probabilities, we crave certainty.
  • Any radiation exposure increases the probability of getting cancer. There is no safe dose. A small dose, or even many small doses, does not mean that "it is likely" you will get cancer. It means that "it is more likely" than without this radiation. A few things increase the cancer likelihood so much to make cancer almost certain unless something else kills you first, like filming a movie at a nuclear test site.
  • Take smoking as another example. There are many stories of people who chain-smoked to an old age and never got cancer, and others who got lung cancer despite never smoking, but on average smoking correlates with various types of cancer.
  • So you should avoid any avoidable radiation exposure, but if you hide in the basement you may get cancer from that, too. To give you another example, you shouldn't get x-rays for the fun of it, but if your doctor suggests to take one, that's probably better for your health than proceeding without the diagnostic information.

Minimize radiation where you can. Where you can't, then accept the risk and live with it. Ultimately birth leads to death.

Follow-Up: The US Environmental Protection Agency uses the linear no-threshold model. While quoting this isn't scientific proof, I think it is prudent to avoid any unnecessary radiation exposure.

It is also sane to put this risk into perspective -- eating chips and charred burgers increases cancer risks as well, and so does jogging next to a busy street.

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    Everything will kill you – John Dvorak Sep 8 '18 at 16:09
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    The #1 cause of cancer is being alive. Dead people don't get cancer. – Nelson Sep 8 '18 at 17:31
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    @Nelson, different groups of people get cancer at different rates. That is relevant. – o.m. Sep 8 '18 at 17:54
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    Note that the linear model (that there's "no safe dose") is contested by a number of scientific organizations, see: en.wikipedia.org/wiki/Linear_no-threshold_model#Controversy – cartographer Sep 8 '18 at 23:33
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    according to Wikipedia, you'll get one micromort due to increased cancer risk due radiation for each 10000 km / 6000 miles travelled by jet. Compare that to one micromort for travelling 370 km / 230 miles by car (due to risk of accident). – Andre Holzner Sep 9 '18 at 9:51

Your calculations are reasonable, but I am not sure if you understand or just misquote the EU Basic Safety Standards directive.

I assume that you are referring to article 12 of the directive: "Dose limits for public exposure". This article limits the amount of artificial radiation, which you as a member of the public can additionaly be exposed to by 'authorised practices' in your surroundings to an equivalent effective dose of 1 mSv per year. I can't find any numbers for Europe, but US residents are for example on average in total exposed to an equivalent of 6 mSv per year, most of which actually come from medical examinations.

For special groups, the limits in the BSS directive are set much higher:

  • Airline crew can be exposed to an additional 6 mSv per year.
  • Employees handling radioactive matieral can be exposed to 20 mSv per year, or in exceptional cases even 50 mSv per year. The radiation exposure may over a period of 5 years not exceed 100 mSv and during the lifetime of the worker not exceed 400 mSv.
  • Emergency workers may 'in exceptional situations, in order to save life, prevent severe radiation-induced health effects, or prevent the development of catastrophic conditions' be exposed to up to 500 mSv.

As you can see, your additional 0.5 mSv per year from flying is just a fraction of the legal limitation to radiation exposure.

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    This is an issue of "informed consent". Airline crews, radiation workers, and emergency workers (should) know about the additional risk and take it knowingly. Likewise, when a medical procedure is undertaken, it is judged that the benefits of medical treatment outweigh the risks of radiation. (i.e. early detection of cancer from mammograms saves more lives than the additional cancer deaths from x-ray exposure). Thus, the OP should be aware that they are incurring an additional risk and they must judge themselves whether it is acceptable, or whether they should find a new job. – user71659 Sep 8 '18 at 18:08
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    an interesting point though (in my opinion) is that radiation workers carry dosimeters while airline crew members do not as far as I know. Or is there a dosimeter onboard ? – Andre Holzner Sep 9 '18 at 9:56
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    @AndreHolzner As far as I understand it, the dose is rather predictable, so airlines use software to estimate the dose based on the flight paths of all of the flights that each crew member has been on. – alex.forencich Sep 9 '18 at 20:59

I am a cabin crewmember, I did anything from as much as 10 flights per month to 35 flights per month (around 80-100 hours flight time) for years and still alive and fine.

Crewmembers follow a complicated system that regulate rest periods between flights and flying hours per month and many other things. This does not apply to passengers, they are not exposed as much as crewmembers and they don't do 4 or 5 flights a day as some crewmembers do. These regulations are well studied and are based on medical studies and a lot of organizations are involved in it to make sure it's safe for crewmembers. Considering that crewmembers do fly way more than passengers, then it's quite safe to assume that it's safe to fly 60 flights a year.

In my opinion, the only thing you really need to worry about is staying hydrated and moving from time to time to avoid blood clots in your legs.


While the others have correctly addressed the risks associated with increased radiation, I feel important to stress out other risks associated with flying:

  • Fatigue
  • Sleep deprivation
  • Low air pressure
  • Dry air
  • Germs from fellow passengers
  • Turbulence (potentially causing injury)

Even if you always fly business class and only have carry-on luggage, at 60 flights per year you're likely to encounter flight delays and cancellations, flights leaving at inconvenient times, traffic jams on the way to the airport, etc, etc. Not to mention flying every single week leaves you less time for proper exercise and encourages eating unhealthy airport/airline food. All of these factors are likely to factor into your life expectancy a lot more than radiation alone.

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    OP may - just possibly - have some awareness of these things ..."For the fifth year in a row I flew approximately 60 times" – mcalex Sep 10 '18 at 3:50
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    @mcalex yes, but psychologically speaking people are more scared of unseen threats (radiation) than they are of obvious threats (lack of sleep). – JonathanReez Sep 10 '18 at 3:56

In short, no, you shouldn't be concerned.

The radiation dose is very tolerable, and with sufficient pause in between (at 60 flights per year you have on the average 6 days, which is plenty) it's neglegible.

Sure, you may get cancer (nobody can guarantee you won't!), but if you do, you can't blame your travels for it. In all likelihood you would have gotten it anyway, and nobody will be able to tell why. May as well be from the water you drank or cancerogens in your food, or certain virus, or just... bad luck.

Radiation is a naturally occurring phenomenon, and the dose you worry about is way less than what flight crew tolerates easily and without any health issues. The unavoidable constant background radiation, while significantly lower, is probably just as harmful as the intermittent slightly higher exposure. Living in a concrete building is much more harmful (and no one worries about that, me included!), as the higher-than-average radiation is permanently present, not intermittent.

Even at the much higher doses that flight crew is exposed to (dozens of times more, over decades) your body is perfectly able to repair the damage, provided that there are rest periods in between (at least a day). Nature (or evolution, call it what you will) has -- within limits -- adapted to, and can cope with radiation and its damaging effects. DNA repair is a fundamentally important part of life. You couldn't ever go out in the sun, if it didn't work (at least, for the most part) reliably.

In radiotherapy, you get two-digit Grays over a couple of weeks (which, depending on tissue, corresponds to single-digit, double-digit, or triple-digit Sieverts). Not milli, not micro. So basically around ten million times the dose you worry about.
While such a huge dose doesn't truly go down "no effect" on surrounding tissue, even at these massively harmful doses the effects are surprisingly mild provided that there's sufficient rest periods between exposures. This is the entire point of radiotherapy. Healthy tissue will regenerate damage during the rest period whereas tumor won't.


You have to remember that you get radiation even at sea level, and there's no way to escape that. Even from eating bananas. From Wikipedia, you can see that a flight only increases the radiation by 10 times, while you are in the air, so a 1 hour flight once a week (168 hr) increases your radiation by 10/168 = 6%!

Note also that the extremely conservative DOE annual limit is 20 mSv ~ 4000 flights. So no, I would worry more about getting shot out the air or getting lost in the Bermuda triangle.

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