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Cancer-related mortality among US pilots and flight attendants

cnn.com

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Re: Cancer-related mortality among US pilots and flight attendants

#81

Post by SiempreViernes »

leonidasrup wrote: post #75
sigmoid10 wrote: post #51

Earlier quoted context omitted.

Depends on the actual scan. A head CT can be as little as one sievert while a full blown angiogramm can be more than ten sievert. A pilot can accrue 40k flight hours over his career. If 90% of that is at cruising altitude (meaning 3-6 microsievert/hour), that would be 100-200 mSv in total. That would be equivalent to more than a hundred head CTs or a dozen angios. If you need that many CTs, your lifetime cancer risk…

Air crew radiation exposure depends strongly on cruising altitude and Latitude, for example flight Tokyo JP – New York NY is about 67 microsievert. https://www2.ans.org/pubs/magazines/nn/docs/2000-1-3.pdf For general comparison astronauts are exposed to approximately 72 millisieverts (mSv) while on six-month-duration missions to the International Space Station (ISS). https://en.wikipedia.org/wiki/Effects_of_ionizing_…

> In terms of absolute risk, about 6.9% of flight attendant deaths were from these cancers — roughly 1 in 14. Among pilots, it was 6.7%. For the general working population, it was 5%, said the study’s first author, Dr. Vishal Patel of Harvard Medical School.

So it looks like LNT is maybe a bit too optimistic at low doses, because (with the caveat I'm not entirely sure what precisely these percentages mean) the reported excesses are 1.9 and 1.7 percentage points.

Re: Cancer-related mortality among US pilots and flight attendants

#82

Post by zeroc8 »

technothrasher wrote: post #12
4d4m wrote: post #8

Boeing, Bombardier, Learjet, Embraer and Airbus should be forced to clean up aircraft cabin air they poison us with. For people who don’t know how GROSS this is: on almost every modern passenger jet, the air you breathe is pulled through the engine’s Bleed-Air system before entering the cabin. As oil, hydraulic fluid, or other contaminants leak into that system, those superheated fumes can be pumped directly into the…

> These incidents are literally called "fume events" Your first FAA link says that these 'fume events' are rare: "The report found that the rate of cabin air quality events is less than 33 events per million aircraft departures." This is about one event every 30,000 flights.

There are more than 100,000 flights per day. So not that rare at all.

Re: Cancer-related mortality among US pilots and flight attendants

#83

Post by giov4 »

triceratops wrote: post #47
NegativeLatency wrote: post #28

Earlier quoted context omitted.

I have a pretty sensitive sense of smell, and I regularly smell oil/smoke/hydrocarbon smell after they're starting the engines. It also sticks on your clothes after the plane ride, and I'm quite sure it's not just stinky seat smell.

I don't have a sensitive sense of smell and I still smell it.

I also don't have a pretty sensitive smell and I smelled it a lot, especially cherosene like while boarding and before or during taxing, but later gets better.

it happened to me only on certain planes or cheaper airlines and i never managed to correlate it enough to plane, situation or airline.

the smell is very pungent and scratches the throats, typical fulel /exhaust like.

I learned about the air system passing through the motor because of the safety incident case, where the safety for engine malfunctioned and junctioned high temperature engine oil into the air system when triggered, causing cabin and pilot problems breathing and visibility.

does anybody know which conditions usually trigger this fuel like smell and perhaps which engine models are more prone to such condition?

the fact that it goes away when flying let me me think something related to systems used when on ground

Re: Cancer-related mortality among US pilots and flight attendants

#84

Post by leonidasrup »

SiempreViernes wrote: post #81
leonidasrup wrote: post #75

Earlier quoted context omitted.

Air crew radiation exposure depends strongly on cruising altitude and Latitude, for example flight Tokyo JP – New York NY is about 67 microsievert. https://www2.ans.org/pubs/magazines/nn/docs/2000-1-3.pdf For general comparison astronauts are exposed to approximately 72 millisieverts (mSv) while on six-month-duration missions to the International Space Station (ISS). https://en.wikipedia.org/wiki/Effects_of_ionizing_…

> In terms of absolute risk, about 6.9% of flight attendant deaths were from these cancers — roughly 1 in 14. Among pilots, it was 6.7%. For the general working population, it was 5%, said the study’s first author, Dr. Vishal Patel of Harvard Medical School. So it looks like LNT is maybe a bit too optimistic at low doses, because (with the caveat I'm not entirely sure what precisely these percentages mean) the report…

Without access to the study and study data we don't know what was measured and how it was calculated, because the value for absolute risk in general working population, the value 5%, is very different from other cancer death studies.

According the The American Cancer Society the risk of dying from any cancer is 17.2% for males, 16% for females for the overall US population.

https://www.cancer.org/cancer/risk-prevention/understanding-...

Re: Cancer-related mortality among US pilots and flight attendants

#86

Post by gib444 »

4d4m wrote: post #8

Boeing, Bombardier, Learjet, Embraer and Airbus should be forced to clean up aircraft cabin air they poison us with. For people who don’t know how GROSS this is: on almost every modern passenger jet, the air you breathe is pulled through the engine’s Bleed-Air system before entering the cabin. As oil, hydraulic fluid, or other contaminants leak into that system, those superheated fumes can be pumped directly into the…

The 787 in economy (as configured by most airlines) is hell in every other way so boy what a quandary

Re: Cancer-related mortality among US pilots and flight attendants

#87

Post by dezgeg »

jader201 wrote: post #22
RajT88 wrote: post #7

Attendants have higher risk than pilots. This kind of makes sense, as my understanding is they don't have pilots fly too often. Meanwhile, attendants are flying all the time.

> as my understanding is they don't have pilots fly too often From a quick search, I can’t find evidence of this. If anything, pilots are in the air more of their week/lives vs. flight attendants.

I wonder if pilots' medical checks would catch some of these early?

Re: Cancer-related mortality among US pilots and flight attendants

#88

Post by mrguyorama »

giov4 wrote: post #83
triceratops wrote: post #47

Earlier quoted context omitted.

I don't have a sensitive sense of smell and I still smell it.

I also don't have a pretty sensitive smell and I smelled it a lot, especially cherosene like while boarding and before or during taxing, but later gets better. it happened to me only on certain planes or cheaper airlines and i never managed to correlate it enough to plane, situation or airline. the smell is very pungent and scratches the throats, typical fulel /exhaust like. I learned about the air system passing thr…

The conditions that trigger the "Fuel like smell" of kerosene is that you are in a place where thousands of gallons of actual kerosene are handled, moved, spilled, and burned every day.

The air quality at an airport is horrific, in general, and as long as the plane is on the ground, it will be moving that air into the cabin.

People notice it because you go from highly filtered, airport air, to unfiltered air on the jetway, to possibly filtered (depending on specifics) air from the ground equipment, to bleed pack air.

It goes away when you are flying because the air quality 4000 feet above the airport is so much better.

The oil seals in a jet engine are not magically perfect, and so there is absolutely some miniscule amount getting into bleed air. But bleed air comes out from the compressor section, before any fuel can be there, and modern jet engines are exceptionally good one way valves (compressor stall is the term for when they aren't). Engine oil consumption is also monitored for every single flight, but not to that level of precision.

If the smell goes away in the air, it cannot be related to small amounts of oil vapor coming from the engine compressor section. Because that would still be present at 30k feet.

Re: Cancer-related mortality among US pilots and flight attendants

#89

Post by thrill »

dezgeg wrote: post #87
jader201 wrote: post #22

Earlier quoted context omitted.

> as my understanding is they don't have pilots fly too often From a quick search, I can’t find evidence of this. If anything, pilots are in the air more of their week/lives vs. flight attendants.

I wonder if pilots' medical checks would catch some of these early?

Probably not unless there was something presenting, as a Class 1 FAA medical exam is checking medical history, vital signs, vision, hearing, cardiovascular health, neurological function, and general physical condition. There's a urine test for blood, glucose, protein. Last one I had there was no blood test or cancer screening unless it was something showing on the skin.

Interestingly, to me, my last medical was 2 years ago and there was no concern for the spot on my cheek that turned out to be basal cell carcinoma.

Re: Cancer-related mortality among US pilots and flight attendants

#90

Post by mrguyorama »

wiredfool wrote: post #41
ch4s3 wrote: post #29

Earlier quoted context omitted.

I’ve never noticed this in 35 years and I have an unusually sensitive sense of smell.

I don’t think I’ve noticed gym socks smells, but I can certainly smell kerosene basically every time when outdoors at the airport, and often in the plane.

This is because it's an airport and there are tens of thousands of gallons of kerosene around, including several gallons per minute per running jet engine actively burning and turning into combustion products.

Even in a perfectly working bleed air system, the air comes from outside the plane, which on the tarmac of an airport, is god awful, shitty, and not at all healthy.

Lot's of other commenters talking about how the smell goes away at altitude.

Because it doesn't come from the packs (except in fume events), and what people are usually smelling is that airports have very bad air, and that air is much cleaner at 30k feet.

The miniscule oil vapor/droplets that are making their way into the bleed air system from engine compressor seals will still happen at 30k feet. If you don't smell something at all times on a plane, it cannot be coming from that.

This level of contamination would be like working at a gas station, which can be a health hazard. OSHA regulates air quality for employees working around hydrocarbons.

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