Cancer Amongst Pilots
 

Gentlemen.

Im thinking on these lines because three of my friends have been diagnosed with cancer lately. Im not at all convinced that radiation is to blame here (most likely coincidence?) but all those gentlemen are airline pilots. It also got me thinking about radiation because lately I had an x-ray done and my doctor used this massive led suit for protection. I know there has been some research and Id like to know the latest findings if some of you are educated enough to help me out. I have 4 questions:

1.Has it ever been proved that radiation is higher at jet altitudes (FL300 and up)?
2.If so, is this radiation strong enough to affect the health of people over time?
3.Is there any study that suggests cancer is more common amongs airline crews?
4.Do any airlines limit the number of flying hours for crew in regards to radiation?


I love flying – just like to know if we are taking this aspect of flying serious enough.
Thanks

Hello!

The answer to questions 1, 2 and 4 is "Yes", regarding question 3 I have never heard about a relevant study.

Here in Europe, at least since the implemetation of JAR-OPS, crews of high flying aircraft are required to attend seminars on radiation risks at regular intervals (like CRM, dngerous good, firefighting and so on).

Greetings, Max

This probably belongs in the medical section, but worth reading none the less. What follows is one doctors opinion of x-rays and cat scans...

"
S&A HEALTH REPORT: The Danger of Detection
By Dr. David Eifrig Jr.
For the past two years, I have had the pleasure of staying at the Union League in Philadelphia for a week, while attending an annual review course sponsored by the University of Pennsylvania. This year, as last year, the pressure to learn was intense. The daily lectures began at 7:15 a.m. and ended approximately 12 hours later! Lunch was provided, but often the scheduled time to eat was shortened because the morning lecture didn't end on time. Whew… I learned a lot, but most of it is still sinking in. By the way, if you ever get a chance to learn about the history of the Union League, I encourage you to do so. Its motto is "Love of Country Leads." It was founded in 1862 as a society to support President Lincoln. It is a fascinating place and the employees are about as loyal as any I have ever met. The Union League is to the movers and shakers of American politics as The Augusta National is to golf.
Okay, enough of the travel diary and on to the point. One of this year's speakers at the review course reminded us of something he said last year. I had apparently ignored it last year, but this time it hit home in a big way.
According to David Abramson, the first-ever Chief of the Ophthalmic Oncology Service at Memorial Sloan-Kettering Cancer Center, "Diagnostic X-rays cause close to 1% of all deaths in the U.S., and 3.5% of all deaths in Japan." Moreover, he told us, "You should never let a child get a CT". A CT, or computer tomography, is essentially a large number of consecutive or serial X-rays taken all at once and then analyzed by computers using fancy algorithms. This was jaw-dropping because I myself have ordered hundreds of CTs on adults and children. It turns out that terminal cancers that occur years later are not easily traced back to the earlier exposures.
Suspicions that radiation from X-rays and CTs cause long-term health problems have been around for a long time. But because the cancers are slow-growing and insidious, it has taken a long time to uncover the real risks. Only in the past 10 years have scientists truly questioned the benefits versus risks of detection via CT or X-ray.
What this means for you and me is unclear, but for us as a group the dangers are real. Researchers at Columbia University put the risk for getting cancer at 1 out of 1,000 from exposure to radiation from the now-commercially available whole-body scans. In addition, the false positive rates from these machines are high. This means that the scan finds anomalies that are not truly disease-causing or debilitating. The anomalies don't need treatment, but they show up on the scans as "positive." On top of this, these whole-body tests are usually hyped as health-promoting when, in fact, they are not. Even worse, they are expensive.
What is scary, though, is that the studies your doctor might order could easily be useless as well as dangerous. Yet, we trust our doctor to make these decisions. Be careful. Is your doctor ordering tests to help with diagnosis, or to CTA (Cover Their A**)? You see, even if the CT were to pick up a true disease entity (for example, prostate cancer), there is very little evidence that early detection in certain diseases (especially slow-growing ones) makes any difference in quality or length of life. For those with a disease detected early and no symptoms, the psychological impact of knowing you have a disease can be spiritually and physically devastating. It is possible that the psychological impact is more devastating than the disease would be, and could lead to earlier morbidity and mortality. In fact, a Mayo study of lung-cancer screening found that people in the screening group died earlier than those not screened with CTs. Hmmm.…
In a Japanese study, CT screenings flagged equal numbers of smokers and non-smokers for lung cancer. Thus, CTs failed as a screening tool for cancer in smokers, and worse, put many people at risk for cancer from the radiation exposure of the CT.
The confounding variable in all this is that doctors are taught to do things based on assigning value to a result. So ordering a test and acting on it becomes a very natural step for doctors. Sometimes they act even if the result is logically flawed. Surprisingly and dangerously, treating a false positive from a lab or test result is quite common. Ironically, the real problem comes when doctors treat a false positive and, seeing improvement, assume falsely the treatment worked.
This statistic will blow you away: After 10 yearly mammograms for women 50 years old or older, the cumulative false positive rate rises to almost 50%. What! How can this be so? Your doctor certainly won't tell you this. Does your doctor even know? And what happens is that the poor woman is exposed to more radiation and more risk of cancers as the doctor tries to figure out whether she really does have the disease. The key is to assess the risk clinically before exposing a woman to radiation. The math is slightly complicated, but by stratifying patients in to pre-test probabilities for disease…the correct and, hopefully, safest test might be ordered.
The fact is that CTs and the haphazard recommendations to get them when the clinical signs and symptoms don't warrant them are inexcusable. Just recently I read of a child getting head CTs when the clinical suspicions were quite low. The poor child's head was only exposed to the CT radiation because of the parents' prodding and the doctor's fear. Again, this is exposure that has been shown to lead to cancer, and could have been prevented by informed and fearless parents and doctors. Sadly, most doctors will argue that they have to order them to avoid being sued, commonly saying that they've never been sued for ordering a test, only for not ordering one.
When it comes to radiation... What do I do?
Here's to our health,
David Eifrig Jr., M.D., M.B.A.
"

I once took a small Geiger counter to work with me to do my own experiment. I flew from London to Hong Kong then from Hong Kong to Melbourne and back.
I found a marked increase in radiation above FL250 above which level increases in radiation became roughly linearly proportional to altitude. Radiation was also proportional to latitude being much higher at higher latitudes falling at lower altitudes with a very marked drop when crossing the equator.
My Geiger counter only measured ionising radiation ( Alpha & Beta ) so Gama and X-ray didn’t register at all. I would post the figures here but they were all lost when I upgraded my PDA, sorry. As I recall the radiation levels never quite reached published danger levels but they weren’t far away.
I do have anecdotal evidence however that the levels on aircraft are high enough to cause concern in other industries. I used to work in atomic energy research. A colleague of mine took his family on holiday to Florida. He inadvertently packed his film badge dosimeter in his suitcase. He discovered it while on holiday but thought little of it. Some time after his return to work a routine test of film badges in his section almost caused an emergency shut down of the site. The radiation he had collected on his two sectors was enough to indicate a possible leak in one of the reactors.
Kirk out…

Hi!

I did a little google search and found these two refences to studies that both link the occurrence of cancer among pilots to the frequent disturbance of the biological rhythm of the body rather than to the higher radiation levels:

http://news.bbc.co.uk/1/hi/health/645113.stm

and

http://www.ncbi.nlm.nih.gov/entrez/q...&dopt=Abstract

Greetings, Max

So turboprops are good for your health after all?

Of course! You'll live a longer and healthier life, you just won't be able to hear your grandchildren's laughter! :}

Just kidding of course. I love my turboprop buddies. They always give me a nice ride to the next gateway.

Ever heard of "Medical & Health" . . .14th Forum from the top :eek:

My local dentist has a notice up about dental x-rays where they point out that you get a bigger dose of radiation flying to Spain and back than you do from one of their x-rays.

At the risk of sounding condecending, do you think that the High levels of radiation exposure mentioned above have anything to do with the luggage going through x-ray security machines. But for the record Our Company OPS Manual has 4 pages on Cosmic radiation exposure but not much on sleep deprevation:ugh:

There is not only the issue of radiation and irregular sleep as a health risk. I do also know a lot of collegues who live a very unhealthy lifestyle in general: Eating, drinking, lack of body exercise, high body mass index, smoking, promiscuity, stress etc. Do you want to know more?

Pilots are in general more conservative people, less influenced by new fashions and ideas, and therefore somewhat immune to new movements in health and living.

Dani

@Dani

and others.

All true!

Check the slowfood-people. Founded in Italy.

http://www.slowfood.de/

Are low doses of radiation harmful?
 

Some research suggests they may not be:

http://news.bbc.co.uk/1/hi/sci/tech/5173310.stm

The programme suggested that levels of cancer amongst airline pilots should be much higher than they are, if the existing Linear No Threshold model is correct.

NRPB published a report describing why us pilots are classed as radiation industry workers and therefore permitted to have a higher annual dose of radiation compared to 99% of the public. Basically, we'd never do more than 2 months a year if kept to the normal limits. Still low quantities but it makes for an interesting read. One day in (IIRC) the early 1970s you could have had an entire years-worth of radiation in one 8 hour sector at FL330+ from northern Europe to North America. Something to do with sunspot activity and the higher doses received in higher latitudes.

Suggest you contact the NRPB (National Radiological something Board) for more details.

food for thought
 

The University of Iceland (Dr Rasmussen I think) published some leading peer reviewed papers in the late 1990s and early 2000s. There was some evidence that cosmic radiation on long haul flights presented a higher risk. A Swesish study found higher breast cancer rates (than normal background levels) in Swedish female aircrew.

The Concorde flight crews had their fare share of acute myeloid leukemias and cancers- notably prostate. Military cancer rates are higher too- both these groups operate at FL40 -55 +.

The higher you go, the bigger the risk - short duration or long.

Lufthansa implemented a protocol on flight and cabin crews to reduce long haul exposure by mixing and matching long haul crews with short haul work.

The experts I know are predicting long term cosmic radiation effects on crews after 10 -15 years of the ultra-long haul A3340/380 fligths ie SIN-JFK.

But then the radiation levels on the ground in Cornwall are pretty high chaps...And frankly you are more at risk from pesticide residues in your cheap and nasty, clean and bright, supermarket food and the parabens in mens and womens toileteries - especially underarm deoderants...

Flying is safer ...

A fact little recognized in statistics (because it is inherently non-statistical) is that radiation doses from extra-terrestrial sources (the main factor in altitude flying) can vary from zip to phenomenal at any time and place. The natural rad sources in space - whether exploding galaxies or just radiation hot-spots on the sun that spin around to point at earth for days, hours, or seconds - can vary over an energy range of 1,000,000x or more.

High ratios of variation apply to surface radiation levels as well (a point to ponder in relation to 'global warming') but the proportional differences are especially notable high up where atmospheric filtering catches less of the incoming energy.

So it's another kind of lottery. Dosimeters might not be a bad idea for aircrew, but their use also might rock the employment boat more than one would want.

During my degree in physics I had to take a course in radiological protection; while not in any way an expert in these matters, I do recall something very important - pilots do receive higher doses of radiation than the general public, due to cosmic radiation at high altitudes. The higher the altitude, the higher the dose of radiation. However, the yearly doses that pilots receive are well within the safety limits of occupational exposure. Only Concorde pilots (remember at 60,000 ft) flying London-New York return every day would exceed the recommended limits in a year, and no Concorde pilot ever flew every day for a year. (I believe it was in fact my lecturer at the time in Trinity College Dublin, Prof. I M McAuley who did this particular work on radiation exposure in pilots).

Where doctors and dentists are concerned they are exposed to x-rays every day. Long term low-level exposure under those circumstances is a different matter to what pilots receive, due to the nature of the radiation (x-rays vs cosmic rays) and the frequency of the exposure. Heavy lead lined aprons for health workers involved with x-rays is a common sense precaution and not related to radiation exposure for pilots.

For most people working in the airline industry, the additional cancer risks due to occupational exposure are small enough that other factors are much more important. Smoking, for example, makes occupational radiation exposure look very meek indeed. Other environmental factors, radon gas exposure in our homes coming up through the bed rock, is a much greater risk in many parts of many countries, Cornwall already mentioned.

To answer the original questions...

1.Has it ever been proved that radiation is higher at jet altitudes (FL300 and up)?
Yes.

2.If so, is this radiation strong enough to affect the health of people over time?
Not a yes or no answer. The doses received are well within occupational exposure limits. There may be an effect but is is comparable to other environmental health risks and much smaller than some.

3.Is there any study that suggests cancer is more common among airline crews?
I'm sure there are but it would be very difficult to conclusively link any increase in cancer to occupation radiation exposure. For example - do cabin crews smoke more than people in other occupations? Is there a statistically significant link to the number of hours worked and the increased risk of cancer?

4.Do any airlines limit the number of flying hours for crew in regards to radiation?
Not that I am aware of. I am also not aware of any need to.

Not tested
 

Dr. Kev.

Not true we here in Asia have a monitoring programme and crews are kept off the polar routes if they get above 6 something or others.

In addition to what arcniz mentioned. The affects of cosmic or solar radiation on humans has never been studied. All of the "Limits" suggested for flight crew are based on other forms of radiation. So basically we are flying guinea pigs.

FG

This is not actually true. Cosmic particles hitting the upper atmosphere (far above where aircraft can fly) causes cascades of other particles toward the ground. Those particles and their interactions are well known so we actually do know something about the effects on humans. Secondly, exposure limits always err on the side of safety - if we did not know how cosmic or solar radiation affects humans we would assume a worst case scenario and set the exposure limits based on that until better information is obtained. To say we are flying guinea pigs is simply incorrect.

In a manner of speaking, we ARE all guinea pigs - as have been our ancestors and precursors in evolution for thousands of millions of years.

The earth has a cosy skin of atmosphere and a powerfully protective magnetosphere to somewhat dilute the quantity and intensity of incoming ionising radiation. Cruising above a portion of that protection in the stratosphere definitely increases exposure, but the effect is not simple to intuit or measure. Depends on age, gender, diet, genetics and probably a fair amount of luck whether a particular cosmic particle will tear up a particular piece of DNA that will replicate and cause a particular cancer -- or not. Our DNA has learned from all that historical radiation to be very good at repairing itself - and at killing off improperly broken cells, so mama nature helps to mind the store even when we are in zipping around in our spaceships.

Pilots are very easy to identify and track for medical history purposes. So far there seems to be no persuasively documented 'smoking gun' of radiation-related diagnoses in fliers. This contrasts sharply with some workplace chemical exposures that leave an unmistakable trail of illness.

Is good to be cautious, but probably, as Dani says, the fatigue and stress connected with a flying career will get you - if not managed skillfully - long before the glow-in-the-dark stuff.