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A320LGW
8th Apr 2019, 15:30
https://www.dailymail.co.uk/news/article-6898583/British-Airways-pilot-died-inhaling-toxic-engine-fumes-centre-High-Court-case.html

"The family of a British Airways (https://www.dailymail.co.uk/news/british_airways/index.html) pilot who fatally overdosed on sleeping pills after allegedly inhaling poisonous engine fumes are leading a wave of lawsuits being brought against the airline.

Richard Westgate was 43 when he died in 2012 following, according to his family, 'mysterious pains and numbness in his limbs and head' which were caused by exposure to toxic gases that drove him to swallow sedatives to relieve the suffering.

Fresh legal proceedings spearheaded by Mr Westgate's loved ones and backed by almost 100 airline employees have now been brought before the High Court in a 'huge' case which could cost BA tens of millions of pounds."

Herod
8th Apr 2019, 20:41
Are we talking organo-phosphates here?

DaveReidUK
8th Apr 2019, 21:10
Are we talking organo-phosphates here?

Yes, specifically TCP (https://en.wikipedia.org/wiki/Tricresyl_phosphate) (no, not the stuff you have in your medicine cabinet).

WingNut60
9th Apr 2019, 02:07
I have no vested interest in this topic, very little knowledge and will (provided I am not unduly goaded) make only this one post.
I will qualify it now with my strongest empathy for anyone afflicted with illness, whatever the source. Being ill is not nice.
It is especially not nice when it is serious / chronic illness and results in incapacitation and death.

However, now I will put on my devil's advocate horns and the first of two obvious questions.

What does the science say?
I ask this with only the knowledge that the House of Lords Science and Technology Committee investigation put forward a negative finding and their 2008 follow up review affirmed that finding.
I can guess that many here feel that to not be the full story.
What makes the aerotoxicity question philosophically different to the anti-vax arguments?

I am genuinely interested to hear level and measured opinions on this topic.

Water pilot
9th Apr 2019, 03:07
The difference is that there is no credible evidence that vaccines in general cause harm other than some unfortunate but rare reactions. (I qualify this because a specific formulation could contain something generally harmful, like the GMO debate it is in fact possible to create a harmful GMO so saying that GMOs are safe in not accurate.)

There is very good and credible evidence that jet exhaust is harmful, fill a room with it and all the occupants will die. High levels of exposure to the compounds in jet exhaust undoubtedly increase the risk of cancer, the science is clear. Whether the levels that pilots and airline workers are exposed to can cause the sort of harm indicated is way above my pay grade.

DaveReidUK
9th Apr 2019, 06:50
There is very good and credible evidence that jet exhaust is harmful, fill a room with it and all the occupants will die. High levels of exposure to the compounds in jet exhaust undoubtedly increase the risk of cancer, the science is clear. Whether the levels that pilots and airline workers are exposed to can cause the sort of harm indicated is way above my pay grade.

Isn't the argument about exposure to OPs in bleed air, not about combustion products ?

bsieker
9th Apr 2019, 07:32
Isn't the argument about exposure to OPs in bleed air, not about combustion products ?

If you look at how jet engines work, with differential pressures across all seals (driving any contaminants away from the gas path, even if seals leak), and from where bleed air is taken (before fuel is introduced), you will find that if anything other than outside air enters the bleed air path, something has gone seriously wrong with the engine. In all normal and halfway normal and even most abnormal operating conditions there is no way for oil, fuel or combustion products to enter the bleed air.

That is not to say that toxic substances can never enter cabin air systems, in fact there are many credible reports that that has happened, including a lengthy German study (https://www.bfu-web.de/DE/Publikationen/Statistiken/Tabellen-Studien/Tab2014/Studie_Fume_Events_2014.pdf?__blob=publicationFile) (in German, I'm not sure it has been translated), but the engine is unlikely to be the source.

Bernd

GotTheTshirt
9th Apr 2019, 07:38
So they are suing BA ???
What control did BA have over the quality of air entering the cabin ?
Did they have a BA specific procedure?
Are the BA aircraft somehow different from all the other same type engine and aircraft operating?

LAME2
11th Apr 2019, 04:04
[QUOTE.anything other than outside air enters the bleed air path, something has gone seriously wrong with the engine. [/QUOTE]

I remember the crews from Australian Bae146ís. Some took the legal path on this same issue. If I remember correctly, I donít think they proved a link. Happy to be corrected.

chuks
11th Apr 2019, 09:38
We had a test flight once, for a report of smoke coming from a bleed air source, when thick white smoke indeed began to appear about halfway through the takeoff roll. (I seem to recall that it was a bad seal on the engine, but it might have been a bad seal on the pack.) Anyway, yes, something obviously had gone "seriously wrong" there so that I just killed the bleed supply for the affected pack, when we made an emergency return and left it for the engineers to sort out.

We had our masks with goggles on; the engineers observing the test flight got to sit in a cabin full of white smoke for a little while, That was for just a few minutes, but longer than anyone could hold his breath as it slowly dissipated. The real risk then was thick smoke leaving us unable to see the flight displays.

It's easy to imagine that there could be some problem with a pressurization system that puts a certain small amount of contaminant into the air supply, when it would be the flight crew and the cabin crew who get the most exposure.

For one thing, yes, there's a pressure differential between the oil supply and the bleed air supply, but what happens after shut-down? There is no pressure differential, when I assume that a tiny amount of oil could then leak across to the side we get our breathing air from. The 146, of course, has four engines, so that any such effect would be doubled compared to similar aircraft with only two engines. Another thing is that some particular engine design might have less effective seals than another. Too, engines do need to have oil added, even when that is merely a matter of one liter per every ten flight hours or whatever, when we have no real idea where that missing oil went, either safely out the exhaust or perhaps a little bit into the cabin air supply.

Part of the problem is that the basic design for almost all pressurization systems is from a time when we were not sensitive to risks from organophospates. (The Boeing 787 is the only airliner that does not use bleed air for pressurization.) It loosely was taken to be so that if you could not smell it, where was the problem?

Yaw String
11th Apr 2019, 10:07
Sorry,
did i just read someone saying nice things about a Boeing(787)!!!

chuks
11th Apr 2019, 14:22
What do I know?

Actually, the Boeing 707 did not use bleed air directly for pressurization; it used turbo-compressors driven by bleed air but fed by ambient air. I was expecting someone to bring that up.

There's an interesting little experiment you can try using mashed potato. Dye some of it blue and then ask people to compare the taste of that with normal mashed potato. Most normal subjects will find the tinted stuff disgusting. Do that again in the dark: no difference detected.

That's a practical example of the "nocebo effect," the opposite of the "placebo effect." You can experience real, negative effects on flavor from something that works on your mind only because of what you have seen, and what you expect to taste because of that. The bad flavor is real, but it does not come from your taste buds.

In the same way, it may be that some people become ill from bleed air that is perfectly safe, because of that same nocebo effect.

I guarantee you that, sooner or later, someone is going to self-publish an account of how they crawled off a flight on a 787 feeling deathly ill because of contaminated air in the cabin. Not that you would ever want to do this, but I bet that if you went through the cabin of a 787 handing out a questionnaire about "Are you feeling anything wrong because of bleed air contamination?" you would get a few strong complaints.

That is not to dismiss the idea out of hand that some aircraft may cause real problems by supplying contaminated air, just to say that other things may come into play.

Winemaker
11th Apr 2019, 14:40
As SLF I've certainly gotten blasts of kerosene odored air on startup or while sitting; wind direction is the obvious cause with jet exhaust being blown forward and then re-ingested by the engine(s).

chuks
11th Apr 2019, 18:11
The interesting thing in our case was that we had done a full-power run up with no problems, when the smoke started part way down the runway. I have no idea why it did not start during the run-up. It was one of those things where I was able to look around and see it after the engineers started shouting, because I was PNF, but by then we were probably too close to V1 for the PF to have managed a nice, tidy abort, even if I had been able to tell him what the problem was.

This was a Dornier 328Jet, which has one bleed and pack for the flight deck, and another bleed and pack for the cabin. The smoke only came out in the cabin, but really pouring out, just like stage smoke.

I don't know even know what it smelled like because I had my mask on just after I saw the smoke start. I shut off the bleed for the cabin pack, when the smoke stopped coming out fairly quickly, but still lingered. Then I swapped to PF so that the Captain could put on his mask; after that we swapped back again. If that had been a problem with the other side then it might have been a different story, with too much smoke in the cockpit to see what we were doing. The long-term effects of bleed air contamination would not have been much of a problem then!

LAME2
11th Apr 2019, 19:05
Quick google results

https://www.aph.gov.au/binaries/senate/committee/rrat_ctte/completed_inquiries/1999-02/bae/report/report.pdf

11. There has been for some time an occupational health effect suffered by a number of aircrew and cabin crew flying the BAe 146.
12. The record of a connection between an occupational environment problem and the manifestation of consequent health effects on staff, took time to recognise and a longer time to address.
13. As a result those employees who have experienced the most severe health effects have had to either cease flying, transfer from flying on the BAe 146 to other aircraft types or take varying periods of time off work to recover.
14. As the Committee details in the report, a number of these individuals are now in the process of pursuing claims in the appropriate tribunals. They are seeking compensation for the effects they claim result from exposure to poor quality or contaminated air in the BAe 146.

chuks
12th Apr 2019, 03:32
I am not aware of any issues with bleed air contamination affecting the Challenger 600, which also uses the ALF 502 engine used on some models of the BAE 146. You would think that if there's some design defect in the engine that allows oil into the bleed air, then this problem would have appeared on the Challenger 600 as well. (Most Challengers use the CF34 engine, a completely different design.)

I wonder if anyone has had a real close look at the Air Cycle Machine, since an ACM problem might cause contamination.

goeasy
12th Apr 2019, 06:25
I am positive of the effects of this issue. Having had a 319 cabin full of smoke a few years ago. Packs off smoke cleared. Packs were run for Four hours on ground to try and clear contamination before we ferried aircraft home. On arrival ALL crew felt light headed and nauseous, although no smoke was visible during flight. Just the dirty socks smell.

Since then I have been diagnosed with intermittent peripheral neuropathy, with no apparent cause, but likely chemical poisoning. Still flying, but a true believer that this is a valid issue, being blanked by the industry due to the possible legal ramifications.

In reference to the above about seals, it is indeed oil that leaks through when engines not running or during power decreases. It’s evident to investigating engineers there is oil in the bleed ducts that the ACM temps de-compose into the poisonous compounds/smoke. Sad but true, and airlines are hardly likely to be so honest during any investigations.

DaveReidUK
12th Apr 2019, 07:02
I am not aware of any issues with bleed air contamination affecting the Challenger 600, which also uses the ALF 502 engine used on some models of the BAE 146. You would think that if there's some design defect in the engine that allows oil into the bleed air, then this problem would have appeared on the Challenger 600 as well.

I wondered about that too.

But on the other hand,
(a) there are only a few dozen 600 Series flying, out of 1000+ Challengers built,
(b) they fly way fewer hours and cycles than a regional airliner, and
(c) corporate pilots don't tend to take their employers to court as it could be rather career-limiting

speedrestriction
12th Apr 2019, 08:47
Contamination of cabin air with organophosphate originating from lubricants has been scientifically established.

There is clearly an issue of susceptibility whether that is genetic or otherwise. In any case this stuff is not good to breathe in and I am far happier at work knowing my employer (large European low cost) sources their engine oil from a supplier whose oil doesnít have TCP in it.

chuks
13th Apr 2019, 03:22
As far as I know, all synthetic turbine oils contain some sort of organophosphate. (I was told the stuff is there to stabilize the oil, but I have also seen it cited as an "anti-wear compound." Any organophosphate compound may be called TCP, while it may be that it's not literally TCP, and all organophosphates are known neurotoxins.

What brand of oil is your company using, speedrestriction?

Here's an article that shows there's probably not a problem: https://flightsafety.org/asw-article/air-analysis-2/

That would be great news, except that it's directly contradicted by many other articles, such as this one: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3839637/

There was something similar that went on with the oil used in electrical transformers in the States. (Those round cans you see on power poles, for example, are oil-filled transformers.) Sometime in the Seventies it was finally agreed that the oil was highly toxic due to PCB content. Before then there was no real consensus that the stuff could be hazardous.

Profit-driven industries usually do not go looking for problems. Not that industrialists want to poison people, it is simply that they mainly want to make a buck.

Some people go too far trying to make a buck, as with a tragedy in Spain when people may have consumed organophosphates: https://en.wikipedia.org/wiki/Toxic_oil_syndrome

YorkshireTyke
13th Apr 2019, 03:51
.........drove him to swallow sedatives

So self inflicted injury ( death ) ?

Maybe "someone" prescribed them ?

Pinkman
14th Apr 2019, 04:59
As far as I know, all synthetic turbine oils contain some sort of organophosphate. (I was told the stuff is there to stabilize the oil, but I have also seen it cited as an "anti-wear compound." Any organophosphate compound may be called TCP, while it may be that it's not literally TCP, and all organophosphates are known neurotoxins.
I have some interest/knowledge (enough to be dangerous:)) as I am in the fuels industry but have an environmental/toxicology background.
- TCP is Tri Cresyl Phosphate, as opposed to the common antiseptic Tri Chloro Phenol, which is not an organophosphate.
- The TCP we are talking about is an amazingly effective anti wear additive for turbine engines
- This is a bleed air issue not a combustion exhaust issue.
- Alternatives to TCP have been developed for aviation use but AFAIK they don't have the same performance in more demanding turbine applications and I am told by lubricants folk there isn't an effective drop in replacement .."but one day there will be".. probably not helpful, I know. From what I have heard I don't think it's a cost or cost effectiveness issue but confess I don't really know about that part.
- Organophosphates are known to cause the symptoms referenced above but the big problem in getting acceptance of / dealing with this, as a previous poster said, is the individual variation in human sensitivity, both immediate and long term and the lack of any proven dose-response correlation that would enable a performance standard to be set

Hope that helps

goeasy
15th Apr 2019, 04:36
I have some interest/knowledge (enough to be dangerous:)) as I am in the fuels industry but have an environmental/toxicology background.
- TCP is Tri Cresyl Phosphate, as opposed to the common antiseptic Tri Chloro Phenol, which is not an organophosphate.
- The TCP we are talking about is an amazingly effective anti wear additive for turbine engines
- This is a bleed air issue not a combustion exhaust issue.
- Alternatives to TCP have been developed for aviation use but AFAIK they don't have the same performance in more demanding turbine applications and I am told by lubricants folk there isn't an effective drop in replacement .."but one day there will be".. probably not helpful, I know. From what I have heard I don't think it's a cost or cost effectiveness issue but confess I don't really know about that part.
- Organophosphates are known to cause the symptoms referenced above but the big problem in getting acceptance of / dealing with this, as a previous poster said, is the individual variation in human sensitivity, both immediate and long term and the lack of any proven dose-response correlation that would enable a performance standard to be set

Hope that helps

thanks Pinkman, there is far too much mis-information out there, and too many vested interests!