Toxic Cabin Air/Aerotoxic Syndrome
What we really need is a confident blood test to do in these situations to isolate if it was indeed effects of air contamination, and not other issues.
Any attempt at a cover up would be idiotic.
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Southwest Airlines Unusual odours
“A Southwest Airlines flight made an emergency landing Thursday night after crew members reported an "unusual odor" and possibly smoke in the cabin, an FAA spokesperson said.
The Boeing 737 was in the air on its way from Las Vegas to Tulsa, Oklahoma, when the pilot turned around and landed safely at Harry Reid International Airport in Vegas around 8:30 p.m. local time, according to the FAA.
Southwest Airlines told FOX Business in an email Saturday night, "We didn’t find anything abnormal after inspection, aircraft was swapped and continued on to its destination."
The Boeing 737 was in the air on its way from Las Vegas to Tulsa, Oklahoma, when the pilot turned around and landed safely at Harry Reid International Airport in Vegas around 8:30 p.m. local time, according to the FAA.
Southwest Airlines told FOX Business in an email Saturday night, "We didn’t find anything abnormal after inspection, aircraft was swapped and continued on to its destination."
https://www.foxbusiness.com/industri...y43ZoA5lF_JzSw
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Sorry-Related may be in another thread but related to this one.
There are things the authorities can do like pressure for better less toxic oil, push for VOC-Ozone removal and better medical testing post event.
Many times crew do not want to be tested post events for fear of their licenses. Then when they do proper laboratory testing and blood testing is not available.
Hence a accident investigatior cannot find the proof needed, yet over 15 accident investigation branches have made recommendations for things like cabin sensors and improvements.
It appears that 15% of flight cabin crew are much more affected.
“The captain and co-pilot of a British Airways flight were both taken ill in the cockpit after reporting a “foul odour” while flying at 30,000ft.
The pair had been flying a BA Shuttle 13C between Newcastle and London on the morning of 19 October when the incident occurred, landing at Heathrow at around 9.14am”
https://www.independent.co.uk/travel...z8ylsr1wugz6q1
There are things the authorities can do like pressure for better less toxic oil, push for VOC-Ozone removal and better medical testing post event.
Many times crew do not want to be tested post events for fear of their licenses. Then when they do proper laboratory testing and blood testing is not available.
Hence a accident investigatior cannot find the proof needed, yet over 15 accident investigation branches have made recommendations for things like cabin sensors and improvements.
It appears that 15% of flight cabin crew are much more affected.
“The captain and co-pilot of a British Airways flight were both taken ill in the cockpit after reporting a “foul odour” while flying at 30,000ft.
The pair had been flying a BA Shuttle 13C between Newcastle and London on the morning of 19 October when the incident occurred, landing at Heathrow at around 9.14am”
https://www.independent.co.uk/travel...z8ylsr1wugz6q1
There has been a couple of directives issued recently to do with A320 APU shutdown procedures, switching the batteries off too quickly causes incorrect cool down and subsequently, problems on restart.
This is not a new problem but can be traced to rushed procedures at the end of a long day when you just want to turn the lights out and go home.
This is not a new problem but can be traced to rushed procedures at the end of a long day when you just want to turn the lights out and go home.
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At low RPM bleed air is taken from the high pressure comp, any leaks through the labyrinth seals can get into the bleed air. On some types hydraulic lines are routed through the a/c bays and leaks have seeped into the air cycle machine, some of the MD's leaking Skydrol could enter the APU intake....
Spoon PPRuNerist & Mad Inistrator
The following 5 threads on this topic have been merged into this single thread, with redirects left for reference:
New blood test for contaminated air events
BA A320 FO Fumes event, FO incapacitated
Toxic Cabin Air
Aerotoxic Syndrome
Another Contaminated Air Event
New blood test for contaminated air events
BA A320 FO Fumes event, FO incapacitated
Toxic Cabin Air
Aerotoxic Syndrome
Another Contaminated Air Event
I thought id share the following but appreciate they have already been flagged. There is this recent webinar from lock-down that raises some interesting questions. It seems that, in the US anyway, the medical world have accepted that there really is Aerotoxic Syndrome (AS), or at least that crew are exhibiting poisoning by OP/VOC/CO and other nasty things in burnt engine oil.
Aerotoxic Syndrome and Air Travel Safety - National Association of Environmental Medicine - NAEM (US)
Well worth a look if you are remotely interested in the 'science and apparent evidence for AS' - or the 'apparent science and lack of evidence for AS'.....whichever is your POV.
Nonetheless, it appears that the evidence and widening acceptance for AS is building steadily. There also seem to be tests and treatments available if you are unlucky enough to have been (or remain) a sufferer of AS (crew or pax) - or even be one of the few who are genetically predisposed to OP toxicity. Sadly, the slow progress on this has caused the loss of many a good aircrew (and likely, passenger).
You would hope FAA/EASA/CAA/HSE would be all over this (LOL...!) and that the crew unions would be snapping at their heels to get crew tested, treated and protected after a fume event.
In the UK, I think UNITE and ECA are pretty good but not sure about BALPA and VA.....IIRC Prof Bagshaw's slewed view predominated in BALPA - is it any better these days?
What about the rest of the world? I believe things are moving for national legal responsibilities on airlines in the US and AUS......
Aerotoxic Syndrome and Air Travel Safety - National Association of Environmental Medicine - NAEM (US)
Well worth a look if you are remotely interested in the 'science and apparent evidence for AS' - or the 'apparent science and lack of evidence for AS'.....whichever is your POV.
Nonetheless, it appears that the evidence and widening acceptance for AS is building steadily. There also seem to be tests and treatments available if you are unlucky enough to have been (or remain) a sufferer of AS (crew or pax) - or even be one of the few who are genetically predisposed to OP toxicity. Sadly, the slow progress on this has caused the loss of many a good aircrew (and likely, passenger).
You would hope FAA/EASA/CAA/HSE would be all over this (LOL...!) and that the crew unions would be snapping at their heels to get crew tested, treated and protected after a fume event.
In the UK, I think UNITE and ECA are pretty good but not sure about BALPA and VA.....IIRC Prof Bagshaw's slewed view predominated in BALPA - is it any better these days?
What about the rest of the world? I believe things are moving for national legal responsibilities on airlines in the US and AUS......
Apparently not uncommon from certain destinations - often pyrethrim based - mentioned in the webinar at my post #471 but I do also recall the OP 'air bombs' that our Air Load Masters used to set off in the cabin and freight-bay of the Hercs (before engine start) in certain places of the world - normally hot and or wet with lots of local nasty insects and creepy-crawlies. I don't suppose the contents were much good for you.
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Another Fume like odor event
Crew members on a Frontier Airlines flight that landed in San Antonio, Texas, Thursday afternoon reported feeling nauseous after a fume-like odor was reported on the plane.
A spokesperson for Frontier Airlines told FOX Business that flight attendants on flight 990 from Denver to San Antonio noticed the "fume-like odor" and advised the captain.
https://www.foxbusiness.com/lifestyl..._Zs80Z9CTA1g-k
A spokesperson for Frontier Airlines told FOX Business that flight attendants on flight 990 from Denver to San Antonio noticed the "fume-like odor" and advised the captain.
https://www.foxbusiness.com/lifestyl..._Zs80Z9CTA1g-k
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I have not read the 473 posts in this thread so please excuse me if some of what I write has already been posted. I am not a pilot but my experience with jet engine oils may be helpful. I worked for 38 years with a major manufacturer of synthetic lubricants and have formulated and sold jet engine oils meeting MIL-PRF 23699, MIL-PRF 7808, and AS5780.
As I assume has been discussed here, a main suspect in cabin air sickness is TCP, which is contained in virtually all of the above spec oils at a 2-3% level. This additive is for anti-wear and ferrous metal inhibition. The balance of these oils is ~94-96% synthetic polyol ester, 2-3% amine type anti-oxidants, and small amounts of yellow metal inhibitors, anti-foam, and other additives. The toxic component in TCP is the ortho isomer, which is a potent neurotoxin. This isomer has cause oral poisonings in the past when levels were high, but the ortho isomer level has since been reduced to very low levels that the manufacturers consider safe. Toxicity is not my area of expertise so I cannot comment on its safety.
The polyol esters used as the base oils in these products are made by reacting neopentyl polyol alcohols with a mixture of short chain fatty acids from C5 to C10. It is the C5 fatty acid that contributes the "dirty sock" smell when the ester breaks down. This smell is not related to the TCP, but its presence may be an indication that the oil is a contributor to the odor.
If the cabin air sickness is caused by the TCP it is not an easy fix. Reformulating a jet engine oil to remove a vital additive is a task that costs millions of dollars and takes about 10 years to gain full approvals. Perhaps a faster approach would be to completely remove the ortho isomer from the TCP, assuming it is the only significant culprit. I'm not sure how practical this would be, but it seems easier than reformulating. Another approach would be a mechanical redesign to prevent oil vapors from entering the cabin, or a filter/scrubber to remove the vapors upon entry. Just speculating here since I was not involved in TCP manufacture and am not a mechanical engineer.
Happy to answer any questions about jet engine oils.
As I assume has been discussed here, a main suspect in cabin air sickness is TCP, which is contained in virtually all of the above spec oils at a 2-3% level. This additive is for anti-wear and ferrous metal inhibition. The balance of these oils is ~94-96% synthetic polyol ester, 2-3% amine type anti-oxidants, and small amounts of yellow metal inhibitors, anti-foam, and other additives. The toxic component in TCP is the ortho isomer, which is a potent neurotoxin. This isomer has cause oral poisonings in the past when levels were high, but the ortho isomer level has since been reduced to very low levels that the manufacturers consider safe. Toxicity is not my area of expertise so I cannot comment on its safety.
The polyol esters used as the base oils in these products are made by reacting neopentyl polyol alcohols with a mixture of short chain fatty acids from C5 to C10. It is the C5 fatty acid that contributes the "dirty sock" smell when the ester breaks down. This smell is not related to the TCP, but its presence may be an indication that the oil is a contributor to the odor.
If the cabin air sickness is caused by the TCP it is not an easy fix. Reformulating a jet engine oil to remove a vital additive is a task that costs millions of dollars and takes about 10 years to gain full approvals. Perhaps a faster approach would be to completely remove the ortho isomer from the TCP, assuming it is the only significant culprit. I'm not sure how practical this would be, but it seems easier than reformulating. Another approach would be a mechanical redesign to prevent oil vapors from entering the cabin, or a filter/scrubber to remove the vapors upon entry. Just speculating here since I was not involved in TCP manufacture and am not a mechanical engineer.
Happy to answer any questions about jet engine oils.
Thanks WCT
I suggest you do have a read of the thread and there a load of good references to scientific papers.
It does seem pretty clear now that the scientists are on the right track. I believe it is widely accepted that O-TCP is one of the main culprits - but, as you mention, there are so many isomers and components of oils (and therefore multiple thermal breakdown products that are equally nasty and also including CO). Also, AS is becoming more more-widely recognised as a medical condition and post-mortem reports often show CNS neuropathy.
That manufacturers, operators and regulators seem to be dragging their feet is another issue. That said, some operators have, in fact, read the writing on the wall and taken some measures - changed engine maint cycles/inspections, changed oils and fitted filters/sensors to some ac.
I also understand that some airline/ac fume event checklists have been updated . Most crew unions have good crew support post-event but am not sure all are on the same page. Passengers are generally not informed/included.
There is still a lot of work to do but I think manufacturers are worried about publicly acknowledging the seriousness of the issue because they fear a long queue of injury claims from crew and pax and that this may be 'catastrophic' for the industry (they say).
BUT the right thing to do - humanly and morally - is to take care of those who have suffered in the past (or are still suffering) .....and move on with ac ac/pressurisation systems akin to the B787 (VC10 if u like).....
Sure, it will hurt the companies share prices but they won't go bust - drug companies know this when introducing new drugs (which is why its takes an age of testing before they are released). To continue to deny the issue is doing the industry no favours in the long run.
I suggest you do have a read of the thread and there a load of good references to scientific papers.
It does seem pretty clear now that the scientists are on the right track. I believe it is widely accepted that O-TCP is one of the main culprits - but, as you mention, there are so many isomers and components of oils (and therefore multiple thermal breakdown products that are equally nasty and also including CO). Also, AS is becoming more more-widely recognised as a medical condition and post-mortem reports often show CNS neuropathy.
That manufacturers, operators and regulators seem to be dragging their feet is another issue. That said, some operators have, in fact, read the writing on the wall and taken some measures - changed engine maint cycles/inspections, changed oils and fitted filters/sensors to some ac.
I also understand that some airline/ac fume event checklists have been updated . Most crew unions have good crew support post-event but am not sure all are on the same page. Passengers are generally not informed/included.
There is still a lot of work to do but I think manufacturers are worried about publicly acknowledging the seriousness of the issue because they fear a long queue of injury claims from crew and pax and that this may be 'catastrophic' for the industry (they say).
BUT the right thing to do - humanly and morally - is to take care of those who have suffered in the past (or are still suffering) .....and move on with ac ac/pressurisation systems akin to the B787 (VC10 if u like).....
Sure, it will hurt the companies share prices but they won't go bust - drug companies know this when introducing new drugs (which is why its takes an age of testing before they are released). To continue to deny the issue is doing the industry no favours in the long run.
Last edited by Flipster130; 29th Nov 2023 at 10:48.
How about requiring constant cabin air quality monitoring for TCP on every airliner?
I understand that a lot of oil makers have removed TCP (esp the o-isomer but the others aren't v nice either) and that airlines are using them - maybe WCT could suggest what other compound they might use?? Even so, as I mentioned, there are lots of other nasties in synthetic oils and the thermal breakdown products thereof. Effective filtration would almost certainly required (see PALL website) but I don't know how CAQ monitoring would work in practice....how accurate its is for all possible contaminants, how easy/expensive it would be to fit and how prone are such systems to false alarms....anyone know more?
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Ester based lubricants have been around for over 70 years and are extensively used in industry for high temperature applications. Polyol esters, which are ~95% of jet engine oils, are non-toxic and are used in food grade lubricants, as well as being biodegradable and often made from renewable resources. Likewise the other ingredients such as amine anti-oxidants, anti-foam, and corrosion inhibitors are in very common use in many applications for many decades without issue, The only application I have ever heard of air quality problems is in aviation, which is why I believe the TCP, and more specifically the ortho isomer, is the primary culprit here. Of course in most other applications people don't generally breath the breakdown vapors so other components may possibly contribute, but more likely to irritation rather than to neurotoxicity. That's more the domain of phosphates.
While I have been retired for over 16 years, I do consult and keep in touch with the industry and technology. Formulation changes move very slowly in aviation oils, and new products ever slower. Last I knew only one jet engine oil substituted another phosphate ester for TCP, and it was not being used in commercial aviation. The TCP producers drove the ortho isomer level down to well under 0.2%, most well below 0.1%, which they consider safe at the low TCP doses used in jet engine oils.
Yes I'm sure other anti-wear/ferrous metal pacifiers can be substituted for TCP, but the development and approval process is extensive and expensive. It would take a lot of incentive to push such a reformulation, which starts with all industry players recognizing and admitting to problem and the oil being the cause, and even then would likely take an industry regulation or legal requirement.
I think that preventing vapors from entering the breathing air is a better solution than reformulating the engine oils.
While I have been retired for over 16 years, I do consult and keep in touch with the industry and technology. Formulation changes move very slowly in aviation oils, and new products ever slower. Last I knew only one jet engine oil substituted another phosphate ester for TCP, and it was not being used in commercial aviation. The TCP producers drove the ortho isomer level down to well under 0.2%, most well below 0.1%, which they consider safe at the low TCP doses used in jet engine oils.
Yes I'm sure other anti-wear/ferrous metal pacifiers can be substituted for TCP, but the development and approval process is extensive and expensive. It would take a lot of incentive to push such a reformulation, which starts with all industry players recognizing and admitting to problem and the oil being the cause, and even then would likely take an industry regulation or legal requirement.
I think that preventing vapors from entering the breathing air is a better solution than reformulating the engine oils.
I wish I could recall what oil maker we used who either, as you say, reduced the TCP content or replaced it...... Gulf or Exxon rings a bell?
The thing is that no-one is shouting about the many advances to push down smelly dog/fume events as a result of pressure from good people like these:
CCAQE
Aerotoxic Association
Until everyone flies ac with a pressurisation system like B787 (my friends who fly this beast say it is a game changer for crews - who arrive at destination, not feeling like a pile of dirty washing) the industry is keeping schtum.....and aviation is not doing the right thing by the unfortunate minority who are made seriously ill by the VOC/CO nasties as a result of their working on older ac with leaky bearing seals and no mitigations.....
The thing is that no-one is shouting about the many advances to push down smelly dog/fume events as a result of pressure from good people like these:
CCAQE
Aerotoxic Association
Until everyone flies ac with a pressurisation system like B787 (my friends who fly this beast say it is a game changer for crews - who arrive at destination, not feeling like a pile of dirty washing) the industry is keeping schtum.....and aviation is not doing the right thing by the unfortunate minority who are made seriously ill by the VOC/CO nasties as a result of their working on older ac with leaky bearing seals and no mitigations.....
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Delta A319 near Ft. Myers on Nov 19th 2023, smoky odour on board
Hello I think your refering to the NYCO oil which I understand is TCP free but has TIPPs and different toxins, yet I understand NYCO is working towards certification of a less toxic oil.
Meanwhile
Aviation Herald
“Incident: Delta A319 near Ft. Myers on Nov 19th 2023, smoky odour on board
By Simon Hradecky, created Tuesday, Nov 21st 2023 16:09Z, last updated Tuesday, Nov 21st 2023 16:09Z
A Delta Airlines Airbus A319-100, registration N341NB performing flight DL-1472 from Key West,FL to Atlanta,GA (USA), was enroute at FL320 about 20nm northeast of Fort Myers,FL (USA) when the crew decided to divert to Fort Myers reporting a smokey odour on board. The aircraft landed safely on Fort Myers' runway 06 about 15 minutes after leaving FL320.
The airline reported there was a smokey odour on board, the crew declared emergency and diverted to Fort Myers, where the aircraft was checked and released to service.
The aircraft was able to continue the flight after about 90 minutes on the ground and reached Atlanta with a delay of about 3 hours.
https://flightaware.com/live/flight/...929Z/KEYW/KATL”
Meanwhile
Aviation Herald
“Incident: Delta A319 near Ft. Myers on Nov 19th 2023, smoky odour on board
By Simon Hradecky, created Tuesday, Nov 21st 2023 16:09Z, last updated Tuesday, Nov 21st 2023 16:09Z
A Delta Airlines Airbus A319-100, registration N341NB performing flight DL-1472 from Key West,FL to Atlanta,GA (USA), was enroute at FL320 about 20nm northeast of Fort Myers,FL (USA) when the crew decided to divert to Fort Myers reporting a smokey odour on board. The aircraft landed safely on Fort Myers' runway 06 about 15 minutes after leaving FL320.
The airline reported there was a smokey odour on board, the crew declared emergency and diverted to Fort Myers, where the aircraft was checked and released to service.
The aircraft was able to continue the flight after about 90 minutes on the ground and reached Atlanta with a delay of about 3 hours.
https://flightaware.com/live/flight/...929Z/KEYW/KATL”