View Full Version : Toxic Cabin Air

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blind pew
11th Apr 2017, 12:07
At some time I read a boeing publicity article that the 787 air conditioning was reverting to prior bleed era because of contamination. Imho this was changed because someone realised that the majority of Boeing's production uses bleed air and the costs of 're engineering would be prohibitive.
After a lot of investigation at Kings, Harley Street and Stoke Podges under the top liver specialist,Rodger Williams, I was put in the military hospital at RAF Halton. After a fortnight I was discharged- my wife told me afterwards that I had been given a week to live which is why I was put into Halton.
I was flying the Trident at the time, maintenance as well as management was lousy and fume incidents were common place. Except for lung problems (grew up east of london during the smog years) I had good health until I suddenly experienced gastro and liver problems.
My flight manager- nicknamed the corporal by the bomber boys- tried to sack me saying that I obviously wasn't suited to flying due to my nervous disposition.
I slowly recovered helped by only flying a week a month.
Ten years later I had a recurrence of the symptoms but more extreme. I was flying the DC10 for SR. Amongst my small group of foreign first officers around a quarter had neurological problems. I also had a friend with WardAir on the DC10 who died after a crossing having had a stress ECG complete with a crash team a few weeks before. I had a similar investigation.
Whilst I am sure that my 70s health problems were caused by a neurotoxin associated with the air con the DC10 incidents could have been larium although that would not have explained the WardAir death.

I contacted all parties who dealt with me in the 70s wrt obtaining my Tox reports to no avail.

I lost my license 22 years ago and since I stopped flying jets some of my symptoms have improved.

As to the corporals' nervous pilot...I've gone on to teaching mountain flying, winching and acrobatics and at 67 I'm climbing mountains and "jumping off".paragliding.

I had contact with an aircraft engineer whose company supplied the turbine lubricants as well skydrol and he said he had no knowledge about organophosphate poisoning. This I can believe as the industry has a long history of manipulation but Until recently I would guess that a lot of this cover up was pure ignorance and incompetence until BALPA suddenly changed tack.
The global implications are immense as are the pesticides, GM engineering and spent uranium munitions and we ignore them.

11th Apr 2017, 13:47
Is this one of those 'inconvenient truths'? Is this smoke without fire, or no smoke at all? Is the cost of acknowledging the problem so prohibitive that it stands no chance? Eternal denial? We still do not know the real long term truth of solar radiation. There is not enough scientific historical data. The problem might be if either are ignored so that scientific data is never collected over a long enough period. It is shelved because the solution is too expensive. It becomes a risk/cost consideration.
Remember the poo-pooing (rubbishing) when health issues from leaded car fuel was first mentioned. The petrol industry thought it was a daft notion; until it was medically confirmed. Same with DVT and cattle class pax. Same with salt quantity & other additives in fast foods and children' health. Same now happening with sugar in everything. One could argue that these latter issues were solved because the costs were reasonable.

Mac the Knife
12th Apr 2017, 22:47
"We still do not know the real long term truth of solar radiation. There is not enough scientific historical data. "

I'd be intrigued to hear your explanation of that statement, having a scientific background and a son who is a physicist.

There IS quite a lot that we don't understand about our sun (like why the solar corona is so hot), but there is also quite a lot that we DO understand. The biological effects of solar UV are reasonably well understood now and there is a fairly good historical record of solar activity from a variety of sources going back a fairly long way.

We know that the Sun is a middle-aged G-type main-sequence star that has not changed dramatically for around 4 billion years and is likely to remain fairly stable for another 5 billion, though there will be periods of increased or decreased solar activity (see Maunder minima, etc.).

Global warming is an undeniable fact and we are at least reasonably sure that some of this is anthropogenic and that we can make it worse.

No, we don't know "..the real long term truth of solar radiation.." because we don't know enough about small-scale solar dynamics.

Trying to equate this with a highly variable and selective "syndrome" with protean and mainly anecdotal manifestations for which the evidence base is several orders of magnitude smaller is, I submit, unreasonable to say the least.

13th Apr 2017, 07:12
I think he means "the truth about long-term exposure to solar radiation", i.e: cosmic ray exposure in high altitude aircraft. This was done to death earlier in the discussion, guess this chap missed that bit.

13th Apr 2017, 21:58
The inquest of Richard Westgate has opened in Salisbury.

(BBC South Today TV)


Toxic air fear pilot Richard Westgate died of overdose, coroner rules - BBC News (http://www.bbc.co.uk/news/uk-england-wiltshire-39591492)

A British Airways co-pilot who feared contaminated cockpit air was poisoning him died from an unintentional overdose of sedatives, a coroner ruled.

Dr Fox earlier ruled that "exposure to organophosphate in the course of his employment as a commercial pilot" was "not a proper issue to be examined by this inquest".

Speaking after the verdict, Mr Westgate's mother, Judith, said: "Medical experts have said organophosphate cannot be ruled out in causing his condition, so the questions remain.

"We know there are more sick passengers and crew, and we hope today will encourage the millions who fly to ask questions to ensure something is done to make sure others don't suffer like our son."

13th Apr 2017, 23:10
I flew aeroplanes, mil & civ, for forty years. No one I know has had problems with toxic cabin air (well apart from a chemical carboy in a freighter breaking). Ciggies, yes; killed one or two. One particular aircraft type seems to have a convincingly bad record.
My GUESS is that a very few people are genetically predisposed to hypersensitivity to any number of foods and environments. The World of the majority is not going to stop for the few - sorry.

18th Jun 2017, 11:30
This thread was started 7 years ago when the High Court of Australia ruled in 2010 that inhaling heated Mobil Jet Oil II was harmful to the lungs. This was several years after the AAIB agreed flight safety was being compromised from contaminated air exposures and recommended to EASA and the FAA that contaminated air detection systems be fitted to all turbine/jet powered aircraft - something that has yet to occur.

This week I see there is a significant paper published in a World Health Organisation journal entitled: 'Aerotoxic Syndrome: A new occupational disease'


The authors are probably the most informed on this issue you could ask for.

One is former Australian pilot Dr Susan Michaelis who not only holds a PhD on the issue but also trained as an air accident investigator at Cranfield and her MSc published last year 'Implementation Of The Requirements For The Provision Of Clean Air In Crew And Passenger Compartments Using The Aircraft Bleed Air System' confirmed that engine seals leak oil as a function of design, not only during seal failures. This explains why the neurotoxic organophosphate tricresyl phosphate has been found on the majority of air samples and interior swab samples taken from the internal surfaces of jet aircraft. This means crews and passengers are exposed on every flight to some degree - this may explain the higher cancer rates and ill health seen in crews confirmed by Harvard and others.

The next author is Order of Australia winner, Dr Jonathan Burdon OA, past President of the Thoracic Society of Australia and New Zealand.

The final author is Professor Vyvyan Howard. A professor in Bioimaging and a medically-qualified toxico-pathologist and the current leader of the Nano Systems Research Group.

I think the paper finally shows this issue has to be taken seriously as does the issue.

So what can be done to keep aviation safe, profitable and resolve this issue?

I understand the solutions to this problem will finally be presented at the industry supported 2017 Aircraft Cabin Air Conference in London on 19/20 September. The event is supported by Pall Aerospace, the GCAQE, Air Canada pilots, Both Australian pilot unions, APFA - the largest flight attendant union in the world, Virgin Atlantic pilots and others.

The solution to this problem I am told from a Flight Ops director I respect and trust, is a modern version of the military spec activated carbon filtration system DHL introduced to their B757 aircraft nearly 10 years ago with huge success.

The new version of this Pall designed filter, according to my source, has already been flight tested on an Airbus A320 aircraft at Spirit in the last month and filters the air coming off the packs with minimal flow rate change - it also comes with warning sensors I am told which will please the AAIB and others.

This will finally resolve an issue first reported by crews in the 1950s and will in one move mitigate a health and flight safety issue that should be addressed.

Some crews report they have flown for years with no health effects - others have lost their careers but ultimately these filters will protect the weakest link - the unborn child, the passengers who pay our wages as crew.

It’s a no-brainer - fit the filters which work and make aviation safer - everyone wins.

For one I will be at the conference in London as this will be big news - well done to all those unions who have championed this issue for so many years, especially the Australians.

18th Jun 2017, 23:58
At least two of the first generation jets did not use engine bleed air in the cabin. The B.707 and DC-8 utilized turbo-compressors to supply cabin air. Engine bleed air of course powered them but they took in ambient air, compressed it and fed it to the environmental air conditioning system. I do not remember ever having any contaminated cabin air reports from those aircraft.
I believe the B787 uses independent compressors (electrically driven?) to supply air for the cabin which in turn should eliminate any contamination. Seems like the way to go as turbo engine oils are a witches brew of truly nasty stuff. Bad enough on the techies hands when maintaining the engine; a lot worse inhaling it after it has been super-heated.

19th Jun 2017, 01:59
After reading the last two posts, came across this interesting USAToday article from 2002. Seems Alaska Airlines was involved with a significant number of fume events, with the two AC types. I can imagine what the verdict was. Some further research dates events as far back as 1974 for 8 airlines in the US. BALPA research on 93 757 crews also reported 1600 fume events. I think the pull quote is "Mysteries are cheaper than fixes".


Ian W
19th Jun 2017, 09:56
Perhaps people should be careful what they wish for. EASA could easily (make up) regulate a life time safe exposure limit after which flight even as a passenger on bleed air pressurized turbojets was severely constrained. It happens in other industries.

Long term the only solution is electric pumped pressurization, it would make the engines run more efficiently too.

19th Jun 2017, 14:15
Long term the only solution is electric pumped pressurization, it would make the engines run more efficiently too.

a quibble if I may

It would be a result rather than a solution to fume events.

In the end there would still be alleged fume events and human maladies searching for a linked cause

19th Jun 2017, 15:56
Perhaps people should be careful what they wish for. EASA could easily (make up) regulate a life time safe exposure limit after which flight even as a passenger on bleed air pressurized turbojets was severely constrained. It happens in other industries.

Long term the only solution is electric pumped pressurization, it would make the engines run more efficiently too.
Allegations would then be made of oil leaks from motor-driven compressor bearings.
Re efficiency, you are still using engine power to drive electric or hydraulic compressors with the attendant electrical, mechanical and thermodynamic losses.

Ian W
19th Jun 2017, 16:02
I think it is simpler to isolate oil in the air from a compressor especially one where a more benign lubricant could be used compared to the use of 7th stage air from within an engine lubricated using a 'total loss' oil system.

19th Jun 2017, 17:59
Another thing to be considered is the temperature of engine bleed air versus the output of a motor-driven cabin air compressor. Engine bleed air is hot to say the least and can decompose engine oils as well as vaporize it. The compression ratio of a motor-driven cabin compressor is far lower, hence output temps would be too and I would think its ability to break down the oil. Agreed, I do not want to breath undecomposed oil either..
APU bleed air and main engine bleed air can also decompose deicing glycol as I have seen where an APU was used to run the air conditioning during deicing and ingested deicing fluid. We had a return to the gate with a lot of nauseated pax.

19th Jun 2017, 18:26
What current turbine engine uses a 'total loss' oil system? Because the ones I'm familiar with are quite the opposite, with extremely low oil consumption rates when healthy (and any lube system can loose oil when it's damaged).
Turbine engines typically consume far more oil when operating at low power/idle - the lube systems use pressure differentials to keep the oil where it's supposed to be and that doesn't work as well with low power and low pressure differentials. That means that an aircraft taxing around an airport typically consumes more oil than it will during cruise.

If anyone was really interested in the subject, the absolute first thing they'd do is start sampling the air around large airports - lots of aircraft operating engines at low power and consuming lots of oil.
That so far no one has tells me everything I need to know.

19th Jun 2017, 20:33
Tricky stuff. It'll be interesting to see how it all pans out.
AFAIK, the only legacy I have, at the age of 75, from noisy, oily ships engine rooms and noisy, oily aircraft is tinnitus.
I know y'all thought I was a 'know it all' 30yo but I'm really a 'know FA' old barsteward :)

Ian W
20th Jun 2017, 14:08
As far as I am aware no-one has run a control measure of outside air all the measurements have been made with a degree of 'confirmation bias' so measures are taken within the cabin as the 'only source' of oily fumes could be from the compressor. And of course swabbing the seats will find traces of the oil contaminants in any aircraft that has taxied up behind another.

Just walking around an apron or down the jetway, smelling the kerosene and other fumes, it becomes obvious that there are a multitude of unmeasured sources. Including, sitting in the departure queue ingesting exhaust from the aircraft ahead and 'conditioning' the cabin air with that. Doesn't matter how good your seals are in that case.

20th Jun 2017, 14:27
Having suffered from this myself, some years back,and still have the odd migraines,2 people,Susan Michaelis( a Medic) and Tristan Loraine(Ex BA) formed an Aerotoxic Association with John Hoyte in the chair,with whom I used to fly!They started the ball rolling a full decade ago with little or no results as the Officialdom stated the Historical Data Base was not sufficient to enable the" Authority"to make a prognosis of any long term health problems!!That is exactly what the Lords and Masters of said Authority said to my Wife down at the Beehive Gatwick,when they removed my licence medical-Luckily just before I was due to retire.Meanwhile a LOT of my old mates have succumbed to a number of cancer related or brain related terminal health problems.
Maybe,at last, something may happem.

20th Jun 2017, 14:45
Oh Yes!!!A Senior moment,but what I meant to add was the French Air Force have experimented with a Vegetable Based Oil that does not have the Carthegens in it,and have obtained reasonable results for Engine Life.These chemicals ,particularly in MobilJet 2,have the capacity to prolong engine life.In BAe years ago on the HS125,we used MobilJet2 to try to prolong the Solar APU which used to have a life of 2/3rds of 5/8ths FA,but failed and the Garret APU was then used and lasted a much longer time,as a result of which MobilJet 2 was used for both the Vipers(Total Loss Oil System) and the Garret 731,with minimal affect on Pax and Cabin.However the more modern Engines seem to churn out a far greater amount of Carsonagenic fumes from Organophosphates.I have not seen any comments with actual Airlines trying a vegetable based engine oil,so maybe no one else except the Fench have done so??

20th Jun 2017, 16:53
I rather think that's missing the point.

The aim is to stop oil residues contaminating the cabin air at all, not to substitute a more benign regime that emulates a flying chip shop.

Dream Buster
15th Aug 2017, 19:24
This industry supported conference is an essential two-day event, providing excellent networking opportunities for those seeking to understand the historical aspects of contaminated air, the flight safety implications, the latest scientific and medical evidence investigating the contaminated air debate and the solutions available to airlines and aircraft operators.

This important international conference mapping the business, regulatory and technical solutions to cabin air contamination, will be the most in-depth conference ever held on this topic.

September 19/20 2017


15th Aug 2017, 21:58
OEMs conspicuous by their absence from the programme. Now there's a surprise.

16th Aug 2017, 06:54

"A recent study (http://www.euro.who.int/__data/assets/pdf_file/0019/341533/5_OriginalResearch_AerotoxicSyndrom_ENG.pdf) from the University of Stirling and the University of Ulster reveals the scale of the problem..."

16th Aug 2017, 08:53

"A recent study (http://www.euro.who.int/__data/assets/pdf_file/0019/341533/5_OriginalResearch_AerotoxicSyndrom_ENG.pdf) from the University of Stirling and the University of Ulster reveals the scale of the problem..."
I notice their study is based on the BAe 146 which was alleged to have a particularly conspicuous problem with bleed air contamination.

16th Aug 2017, 10:12
The problem nowadays is that there are so many publications that you can pretty much publish ANYTHING. If you don't believe me, a skeptic blogger recently published a complete bogus paper (http://www.popularmechanics.com/culture/movies/a27457/scientific-journals-publish-bogus-star-wars-paper/), in THREE different journals, based on midichlorians - yes, the ones from The Force in Star Wars. He even authored them as Dr. Lucas McGeorge and Dr Annette Kin :D

The publication quoted in the Economist appeared in PUBLIC HEALTH PANORAMA. So, how do we know how that journal ranks in the scientific world? A good place to start is ranking sites such as EIGENfactor (http://eigenfactor.org/projects/journalRank/rankings.php?bsearch=PUBLIC+HEALTH+PANORAMA&searchby=journal&orderby=eigenfactor) or SJR (http://www.scimagojr.com/). So how does it rank? Well... It doesn't. Searching for that name returns no result.

So why hasn't this study been published in a reputable journal? Well I'm not an expert in this particular field, but even a cursory look at the paper reveals serious problems. For example what they describe as "Study A" is based on 14% of BAE146 pilots having filled in a health questionnaire (no randomisation, not control group, etc). For those who reported long term health effects, the paper provide a list of ailments and their occurrences. It pretty much reads "ailment A: 1 case; ailment B: 1 case; ailment C: 1 case" etc. So what you have a long list of different health effects that has been clumped together to form a hypothesised "syndrome". I could go on, but you get the idea.

I also looked at the publication list of the author's first paper and the pattern of publishing in very minor journals is clear.

I am not a manager, engine manufacturer employee, etc. I am your average line pilot. With a decent scientific background. Does journal ranking mean everything? No. Does the very poor quality of the study, IMHO, mean that no crew or passenger has ever been affected by fumes? No. But if you're going to worry the paying public and air crews, please back it up with sound scientific data.

Big Bad D
17th Aug 2017, 11:30
OEMs conspicuous by their absence from the programme. Now there's a surprise.

If airframe and engine OEMs were key in the programme there would be even faster criticism and no doubt accusation of this welcome event being some form of cover-up. Do you seriously believe airframe and engine manufacturers will not be present and interested?

18th Aug 2017, 07:39
Permafrost_ATPL makes a very good point, even a cursory glance at this study throws up a lot of potential problems.
Public health panorama is an OK journal but is quite low-ranking. It's not one where I'd expect to see ground breaking research - you'd send that somewhere better. If you see ground breaking research in a journal like this then it should set alarm bells ringing. It's also worth pointing out that pretty much the same research (at least, it contains the same studies without any changes) has been published before. Maybe I miss something, but I don't see anything new in this 'new' paper.

The studies also seem to be expecting a result and then going out to prove it. As Permafrost_ATPL says, there's absolutely no control studies done, no monitoring of other groups. Avoiding that bias is one of the first things you are taught as a scientist. The entire paper is based around positive selection bias, as a researcher it really makes me cringe to see stuff like that.

I've said it before and I'll say it again: This type of pseudo-scientific study undermines the actual evidence for health problems associated with cabin air. It's easy to dismiss other evidence when you also see this type of rubbish being published.
What we need is proper science, proper evidence and an in-depth study to understand both the prevalence of fume events and the effect that these have upon crew. What we have is a bunch of people who appear to come up with the conclusion first and then seek evidence to justify it. This is the worst kind of bad science.

18th Aug 2017, 09:33
In a seminal, instant classic article John P. A. Ioannidis shows Why Most Published Research Findings Are False (http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0020124).

He essentially argues that the only valid findings are of meta-analysis where multiple reproducible studies are used as the basis of a larger study of these studies.

Even Richard Horton, editor of The Lancet, says: up to half of all research may be false (http://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736%2815%2960696-1.pdf):

The case against science is straightforward: much of the
scientific literature, perhaps half, may simply be untrue.
Afflicted by studies with small sample sizes, tiny effects,
invalid exploratory analyses, and flagrant conflicts
of interest, together with an obsession for pursuing
fashionable trends of dubious importance, science has
taken a turn towards darkness. As one participant put
it, “poor methods get results”. The Academy of Medical
Sciences, Medical Research Council, and Biotechnology
and Biological Sciences Research Council have now put
their reputational weight behind an investigation into
these questionable research practices. The apparent
endemicity of bad research behaviour is alarming. In their
quest for telling a compelling story, scientists too often
sculpt data to fi t their preferred theory of the world. Or they
retrofit hypotheses to fi t their data. Journal editors deserve
their fair share of criticism too. We aid and abet the worst

There is a crisis in science, particularly the lack of reproducibility.

its easy
20th Aug 2017, 17:24
What are people's thought on the fact we are starting engine's on push back, so going into the fumes, where oil vapours could be, then turning on the packs to gulp it all in? I notice the acrid stink, to the point it bites my throat.sometimes after a week I wonder if it's fatigue that makes my aching limbs or something else

21st Aug 2017, 02:23
I notice the acrid stink, to the point it bites my throat.sometimes after a week I wonder if it's fatigue that makes my aching limbs or something else

This observation is common throughout the many pages of this thread.

Also equally common in everybody's lives

Association does not equal causation.

We await hard statistical validated scientific data to discuss this kind of subjective observation further.

Dream Buster
23rd Aug 2017, 20:14
Latest on toxic cabin air from BALPA August 2017:

A new path in NHS care for pilots affected by fume events | BALPA (http://blog.balpa.org/Blog/August-2017-(1)/A-new-path-in-NHS-care-for-pilots-affected-by-fume#.WZ1nmxvtZCY.facebook)

From BALPA April 2005:

Proceedings of the BALPA Air Safety and Cabin Air Quality International Aero Industry Conference. Held at Imperial College, London (2005) - Aerotoxic Association (http://aerotoxic.org/information/proceedings-balpa-air-safety-cabin-air-quality-international-aero-industry-conference-held-imperial-college-london/)

Toxic cabin air is either:

A risk or

Not a risk...


Guardian article from 19th August 2017: https://www.theguardian.com/science/2017/aug/19/sick-crew-toxic-air-planes-frequent-flyers-ill

back to Boeing
23rd Aug 2017, 20:16
Knowledge does move on in 12 years

25th Aug 2017, 07:40
There is a crisis in science, particularly the lack of reproducibility.I think that's a bit too extreme, some parts of science are suffering from a reproducibility crisis but it's by no means all-pervasive and - in most cases - is a problem in the 'soft' science subjects.
From BALPA April 2005:...Aerotoxic AssociationThat sounds like an unbiased and reuptable source.:}
I really wish you could start quoting reputable, evidence based sources rather than sources whose reports are based on anecdotes. It'd do your credibility the world of good.

26th Aug 2017, 14:22
I rather think that's missing the point.

The aim is to stop oil residues contaminating the cabin air at all, not to substitute a more benign regime that emulates a flying chip shop.

Bare in mind, its not just exposure to cabin air, its also through skin contacts for ground engineers. I have worked in aviation since 1970, mostly mucking about with turbines. Made a lot of contact with MobilJetII, Shell Aero500 and Exxon 2380. Eventually health and safety got on the scene and I started to wear protection, gloves and barrier creams. Guess what? retired now I suffer from a neurological disease affecting my feet, legs and awful headaches. Although diagnosed they wont make the connections to my aviation background.

Dream Buster
30th Aug 2017, 18:45

Don't shoot the messenger.

its easy
14th Sep 2017, 17:46
This observation is common throughout the many pages of this thread.

Also equally common in everybody's lives

Association does not equal causation.

We await hard statistical validated scientific data to discuss this kind of subjective observation further.

I appreciate correlation isn't causation - I have a degree in physiology and over 10 years experience in pharma before I became a pilot nearly 10 years ago, so understand clinical evidence.

I maintain a log of the events . I am just looking for others experience of such and the idea we draw in the exhaust gases from start up, with associated oil leakage from further down the engine, into the bleed air system as we turn on the packs .

A less glib response would be more appropriate.

Ian W
14th Sep 2017, 18:10
In your log do you include the time spent taxiing behind other aircraft and ingesting their exhaust?
Or even when doing external checks when aircraft are held on the ramp?

Lyneham Lad
17th Sep 2017, 16:23
Surprised no one has mentioned EasyJet's move regarding toxic cabin air.

EasyJet to filter toxic air in cabins (https://www.thetimes.co.uk/article/easyjet-to-filter-toxic-air-in-cabins-6qzrf6sjx?shareToken=399e3dd0d57fc35cf3e909b6bfb5e1d3)

Snip from the article:-
EasyJet is to fit filters to stop toxic fumes entering its passenger cabins and cockpits in a move seen as the industry’s first acknowledgment of “aerotoxic syndrome”.

The condition, long denied by airlines, is feared to be responsible for several deaths of pilots and crew and hundreds of incidents where pilots have fallen ill, sometimes at the controls. Frequent flyers and young children could also be affected, it is claimed.

EasyJet told The Sunday Times that “health concerns” had led it to work with a commercial supplier, Pall Aerospace, to “develop and design a new cabin air filtration system” for testing on the company’s aircraft next year.

17th Sep 2017, 16:32
Pall are the obvious company for the job.
They produced aircraft cabin filters for dealing with tobacco smoke decades ago.
With their vast experience of making all sorts of aircraft and medical filters it is an easy choice

17th Sep 2017, 17:35
I have no idea if toxic air is real. But after 30 years of niggling medical problems (stomach and headache) they all mysteriously disappeared after I stopped flying for a number of years. But how am I to prove a correlation?

19th Sep 2017, 07:33
Many posts hinge on the proof of causal link. All this really demonstrates is that proving a causal link to legal standard for anything is hard. There was a similar rearguard action over agricultural organophosphates in 70's and early 80's relating to near-identical medical issues. Whatever the debate on causality we KNOW aero-engine oil contains OP's. Pushback is where I often experience oily smells. Would it not make sense to delay switching on packs until moving forwards?

19th Sep 2017, 10:07
Would it not make sense to delay switching on packs until moving forwards?

I'm not sure I understand the logic of that..stationary or not you are still going to end up breathing air that has come from the Engine Bleed system.

19th Sep 2017, 10:33
The issue is that even with a perfectly designed and maintained bleed system you'll get a (un)healthy whiff of start-up smoke if the packs are on during/immediately after start-up

19th Sep 2017, 11:38
Ok..FWIW on the the types I'm most familiar with the packs aren't running during the start process, they are off before start and go on after all engines are running.

19th Sep 2017, 13:05
Yes, wiggy; which is often while the aircraft is still pushing backwards

20th Sep 2017, 06:02
Given packs are off for engine start I'm still not sure what the aircraft's movement has to do with it...what would you suggest at airports where the tug does a push and then a pull, and engines are started when you are moving forward or have already moved forward to a release point?

Are you simply saying leave the packs off for a specified time after engines are running, presumably in the hope of burning off any oil, residue or similar that gets into the engine bleed system during engine start?

20th Sep 2017, 08:57
I think that the primary cause of aerotoxic syndrome is not to do with fumes from outside, but burnt oil that gets into the air conditioning giving the "sweaty sock" smell familiar to many who have operated the types notorious for it.
Having flown such a type for over twenty years and experienced the smell briefly on very many occasions and had "fume events" a few times I now have many of the symptoms described in aerotoxic syndrome.
The symptoms are often the same as those experienced by farming organophosphate exposure, which is unsurprising as the oils contain the same chemicals.
The problem is that all this is very difficult to scientifically prove, though I do remember some measurements being taken many years ago in affected aircraft which must have proved the presence of fumes but which nothing was ever heard of.

20th Sep 2017, 09:41
though I do remember some measurements being taken many years ago in affected aircraft which must have proved the presence of fumes but which nothing was ever heard of.There have been numerous studies, none of which (to my knowledge) have seen any meaningful quantities of toxic substances in the cabin air, even during what crews described as fume events.
This report is interesting, for example (https://dspace.lib.cranfield.ac.uk/bitstream/1826/5305/1/AircraftCabinAirSamplingStudyPart1FinalReport%2020110420.pdf ). The downside is the lack of any control study, which makes the results interesting, but not particularly robust. The conclusion is particularly interesting:
Therefore, with respect to the conditions of flight that were experienced during this study, there was no evidence for target pollutants occurring in the cabin air at levels exceeding available health and safety standards and guidelines.

A much more widespread investigation (including controls, airport samples, and home samples) is needed in order to draw meaningful conclusions, though.

20th Sep 2017, 09:55
In 2014 a Dutch research team (https://www.google.nl/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0ahUKEwiU-OrJvrPWAhVLWBoKHfRpA6MQFgg-MAI&url=https%3A%2F%2Fwww.rijksoverheid.nl%2Fbinaries%2Frijksove rheid%2Fdocumenten%2Frapporten%2F2014%2F09%2F15%2Frivm-voortgangsrapportage-voorjaar-2014-tcp-s-in-cabinelucht-van-vliegtuigen%2Frivm-voortgangsrapportage-voorjaar-2014-tcp-s-in-cabinelucht-van-vliegtuigen.pdf&usg=AFQjCNG2KSma4yPxvA30ws8tqmzyR2aN3w) also looked at TC(o)P at flight and during fume events.

The link is in Dutch, but the conclusion was both they did not find any significant concentration of TC(o)P, but could not conclude the symptoms were not a result of the few particles that were found.

21st Sep 2017, 07:14
On the 737, the smell/fumes happen mostly during the first start of the day.
I wonder if it is because of some oil or other contaminants collecting somewhere inside the engine during night stop? They get burned off during start —> smell/fumes?
I find that switching the packs off before start, and keeping them off for a few minutes after engine start, will pretty much eliminate this problem.

Dream Buster
16th Oct 2017, 06:54
Sunday Times article about an easyjet fume event flight.

Note that oil fume events are now called 'smell events'...or 'odor events' in the US.

EasyJet in forced landing as ?smell event? overcomes co?pilot - Aerotoxic Association (http://aerotoxic.org/news/easyjet-forced-landing-smell-event-overcomes-co%E2%80%91pilot/)

16th Oct 2017, 20:34
There are other contaminants that can enter the aircondition system.
Hydraulic and deice fluids to mention two.

17th Oct 2017, 14:57
Could this be a bit like 'nut allergy'?
Perhaps a vanishingly small percentage of people are allergic to tiny amounts of contamination which have no effect on anyone else.
Or maybe their illness was engendered by something unrelated to aircraft air.

No comment re BAe146.

18th Oct 2017, 00:59
Have you ever owned a Citroen 2CV or a VW Beetle? How about those sheet metal boxes around the hot bits of the aircooled cylinders and exhaust connections? Yeah, they are a cheap solution to providing heated air to the cabin. Any chance of an exhaust gasket leak, or fumes from seeping oil heated at n degrees on the cylinder head actually being sucked into the cabin. "Slim to none, let's go with it. Otherwise, geez, you're talking a real costly solution."
Bypass air straight to the cabin? What were they/we thinking?

18th Oct 2017, 09:07
It isn't bypass air; it's bleed air from an compressor stage which supplies an appropriate pressure.
I agree with the risk you mention but there's no such possibility with compressor bleed air. On the ground you can get some re-ingestion of your own and others exhaust gas but airport workers breath that all the time.
The theoretical source of in-flight contamination is a leaking oil seal on the forward fan/compressor bearing.

22nd Oct 2017, 13:51
"airport workers breathe that all the time..." Yes. Including flight crew.

2nd Nov 2017, 17:55
This aircraft situation is nowhere equivalent to the Citroen/Beatle situation. The aircraft uses bleed air bled from the compression section of the engine. Unlike the air in the automobiles you cited, the aircraft air is nowhere exposed to exhaust air nor engine components exposed to combustion. In piston powered aircraft (and even some turbo prop aircraft) cabin air is supplied by an engine driven compressor. On 787 the compressor is driven by an electric motor. Those compressors are functionally no different than the compression section of a turbine engine and no more nor less safe.

5th Nov 2017, 18:14
I agree it's not the same as Citroen/Beetle analogy. But it's not at all true to say bleed air carries the same risk as air from an electric compressor. Even a minor oil leak from a bearing (or anywhere) upstream of the bleed will result in contamination

5th Nov 2017, 19:33
Actually, it is very much the same. The design of most turbine engines means that there is generally only one bearing where an oil leak can result in oil into the compressor air upstream of the bleed off take - which is also the case with most electric compressors.
I'm now retired so I no longer see the daily 21.3 reports, but before I retired there was at least one "fume" event on a 787, reportedly due to an issue with the electric air compressor..

5th Nov 2017, 20:01
The 787 compressors are equipped with air bearings.
Not a single drop of oil in the entire air condition.

5th Nov 2017, 23:39
That was the original design intent - but they couldn't make it work. It uses the same oil as the engine.

6th Nov 2017, 01:12
What's the maximum air temperature if the bearings leak oil in this compressor?

6th Nov 2017, 03:30
That I don't know - I never actually worked the 787 but I do recall reading that they had to abandon the air bearings. But as I noted previously, there's been at least one reported "fume" event on the 787 related to an air cycle machine fault. So it's reasonable to assume it get's hot enough that if there is oil present in can cause a problem.

6th Nov 2017, 09:29
Oil lubrication for an ACM?Yes,on B737 Classic and Dash-8...

Dream Buster
7th Nov 2017, 21:33
Hi All,

Here is part 1 of ‘Poison in the cockpit’ from 2010 & part 2 from 2013

Part 1: https://zembla.bnnvara.nl/nieuws/gif-in-de-cockpit

Part 2: https://www.youtube.com/watch?v=1QfhtaXr2Bs

Part 3 will be tomorrow on 8th November 2017

Part 4 will be on 15th November 2017

Poisoning Cover up - finally exposed...:ok:

https://www.youtube.com/watch?v=3PW84yS7l-Q Dutch TV 8.11.17

Next programme on 15th November 2017...

Dream Buster
15th Nov 2017, 21:26
Uitzending gemist | ZEMBLA, Gif in de cockpit: De belangen op Nederland 3 (http://www.uitzendinggemist.net/aflevering/413873/Zembla.html)


Jimmy Hoffa Rocks
9th Jan 2018, 13:43
You tube video removed, why? Not much discussion on this from the airline pilot community ? Another inconvenient truth or....
Is there a cover up? This issues needs to be studied further for hard facts as the fumes affect us, and there´s not enough facts available.
Shouldn't we ask our airlines, manufacturers, unions, authorities to do a serious hard fact study, as it appears it has been kept quiet. Not to alarm, to find solutions

Airline Workers Warn of 'Toxic Fume Events' on Planes From Bleed Air | Fortune (http://fortune.com/2017/08/09/dangerous-cabin-fumes-planes/)

9th Jan 2018, 14:45
But it's not a problem - after all the German BFU refuse to investigate any and all fume events.

9th Jan 2018, 16:13
This issues needs to be studied further for hard facts as the fumes affect us, and there´s not enough facts available.

Are you proposing that it gets studied until the hard facts support a specific conclusion that there is enough facts?

Please provide an endpoint as we know that people of all walks of life get sick everyday from unknown causes.

The Range
9th Jan 2018, 17:46
The problem is not the "fume events that happen an estimated 2.6 times a day".
The problem is the non-fume events that happen more frequently and don't smell but you
breath along the years.

9th Jan 2018, 18:50
I’ve been exposed. Caused an OJI issue for two months. If every time an event occurred and an immediate landing ensued, this problem would go away quickly. We (myself included) are our own worst enemy.

8th Feb 2018, 11:29
FYI...recent event:

“One flight attendant with extreme breathing issues (editorial note: supposedly the flight attendant the flight crew referred to as showing symptoms of a heart attack) was taken to a hospital, a high level of carbon monoxide was found in the blood samples taken by the hospital. “


Dream Buster
15th Feb 2018, 20:49
BALPA Flight Safety Spotlight - Flight Safety Spotlight February 2018 (http://balpa.newsweaver.com/flightsafetyupdate/17qwbrff7maq03pb47p91l?email=true)

How DO BALPA members continue to let their 'union' get away with not communicating to them a known cause of human ill health?

Read the evidence BALPA published in 2005, after their Contaminated Air Conference in London:

BALPA?s Flight Safety in the Spotlight ? (http://www.aerotoxic.org/balpas-flight-safety-in-the-spotlight/)

16th Feb 2018, 08:20
Because it's not a "known issue", it's a suspected issue.
Research into what's going on is needed, not name-calling and howling.

16th Feb 2018, 13:06

From the article - “. 5 other flight attendants showed symptoms of dizziness, headaches and diarrhea.”

“Poisoned”. But after 90 minutes on the ground the flight departed with the five rapidly unpoisoned f/a’s. An hour is a standard divert ground interrupt. Ninety minutes, in Greenland, is quick work.

John Sawyer
16th Feb 2018, 15:41
“Poisoned”. But after 90 minutes on the ground the flight departed with the five rapidly unpoisoned f/a’s. An hour is a standard divert ground interrupt. Ninety minutes, in Greenland, is quick work.

I recall reading "Air Clues"years ago that exposure to synthetic oil fumes could cause nausea and suicdal tendencies. We found that fumes entered the air conditioning system via worn and incompletly pressurised labyrinth seals,so avoided prolonged peiods of idling,by icreasing revs by 200 or so.

Dream Buster
16th Feb 2018, 21:34
Nemrytter - ill health caused by exposure to toxic fumes is a known issue from the 1950's to present and publicly documented.

If you do not accept any of this known evidence - what exact missing evidence would it take to make you doubt your personal suspicions.

A gas chamber?

18th Feb 2018, 11:29
This is exactly the problem you present: Anyone who suggests that evidence is needed is accused of having "personal suspicions" and then presented with some hysterical comment about gas chambers. Such comments help no-one.

I have no horse in this race, no benefit on either side, no profit to make. I'm a scientist by profession and that means that I know what proper evidence is. I've not seen any of that presented thus far, only suspicions and suppositions.

If the problem is as significant as you suggest then it should be relatively easy to gather evidence to support this (financial investment aside). You need medical reports and air quality samples from a large number of flights. You do not need vague reports and "is believed" style statements.
Let's assume that 'toxic air' is definitely a thing. How will you force airlines to take it seriously? Forum posts and hysteria? Or cold, hard, facts?

Dream Buster
18th Feb 2018, 21:29
Here is some of the early evidence from 1955 with overwhelming evidence ever since - but only for those scientists who can read.


Easyjet wisely changed their engine oil in 2017 to Nyco, a safer formulation and deciding to fit 'bleed air' filters & poison detectors in 2018 is the absolute evidence, but only due to criminal proceedings in a Paris criminal Court.

Get informed and read about the 'Precautionary principle' and don't get hysterical over a past legal win in a public High Court. Turner v's East West airlines. (2010).

East West Airlines Ltd v Turner [2010] Australian High Court Judgement (http://www.aerotoxic.org/east-west-airlines-ltd-v-turner-2010-australian-high-court-judgement/)


19th Feb 2018, 01:30
I understand Airbus operated a flying laboratory that studied cabin air quality starting in 2012. The results were kept secret.

Get informed and read about the 'Precautionary principle'

This is what is behind many US farming and food processing chemicals and techniques being banned in the UK and the EU. As long as manufacturers, regulators, and the airlines can "sow the seeds of doubt" into the debate, progress towards a solution will remain mired in the political muck.

Proof of the stalemate is easily illustrated by the fact that despite scientific findings of central nervous system damage by organophosphates, the industry remains unchanged. Even the mere suggestion by a regulating authority or industry representative that aircraft cabin air is potentially dangerous across the fleet would wreak havoc and is the most likely explanation for why TCP/TOCP oils remain in use, despite their proven toxicity.

The elimination of TEL (tetra ethyl lead) as a motor gasoline additive was a long time coming, despite knowledge of the substance's toxicity in humans since the inception of its use. It wasn't until over a half century later that something was done.

It has been nearly three decades since the WHO had this to say about regulation and the differing physical responses to the toxins:

Because of considerable variation among individuals in sensitivity to TOCP, it is not possible to establish a safe level of exposure" and "TOCP are therefore considered major hazards to human health"

21st Feb 2018, 15:31
I'm writing a dissertation on this very topic at the moment and while there is evidence of toxic fumes present, and cases of illness due to exposure i think that it is a minor issue for passengers but maybe more of a concern for flight crew and cabin crew due to the frequency and exposure time leading to an increased probability of experiencing a "fume event".

21st Feb 2018, 17:17
As part of your research, might I suggest you inhale a snootful of hot organophosphates and tell us if it feels minor?

21st Feb 2018, 17:53
sb sfo,
Maybe I should have said the risks are minimal rather than it is a minor issue, for this I apologise because it is a major issue when it happens, and I'm sure a "snootful of hot organophosphate" would not feel minor.
But an average passenger, lets say, taking 2 return flights of around 2-3 hours each year then yes I believe the "risk" will be low and as suggested in my post, the more frequently an individual flies then the risk of exposure to fumes that may or may not contain hazardous levels of tricresyl phosphate will also increase. I am not saying that toxic fumes are not present and serious fume events do not take place, or that when they occur they are not serious but I do believe that for the average passenger they are rare.

Dream Buster
1st Mar 2018, 20:38

We all drive but few people suffer fatal accidents - equally we all fly and officially there is 'No positive evidence' of ANY injuries caused by toxic air exposure.

But the actual evidence is such that countless people's testimonies report injuries after exposure.

An example of a US passenger from 2000:


As as pilot of 16 years flying the BAe 146 - it nearly killed me.

You need to do some research and find out why the airlines are now urgently putting in the known solutions.

Plus there is an article in this month's Royal Aeronautical Society (RAeS) Journal on toxic cabin air by aviation journalist David Learmount.

Please get informed of the evidence, not what you think is happening on the precautionary principle.

A cover up of the actual data is far more likely.

If anyone can publish the RAeS article here, i'm sure it would be most interesting to read.

There either is a problem or there isn't?

Zaphod Beblebrox
1st Mar 2018, 22:54
This is real! I am sitting at gate T12 in KATL with very sick A319. Maintenance says that the APU was overserviced. They have to do a “burn out” procedure. It is a terrible smell that makes you dizzy. We deplaned and are waiting on a new airplane as that one will be out of service for a while.

Rated De
2nd Mar 2018, 08:47
What is staggering is that the airlines themselves will be sitting on data.

A well structured study could easily show a statistically significant correlation between the health impact of continued exposure to toxic air by looking at sickness rates in the flying crew population and the broader population. There is research into the likely presence of carcinogens and the diagnosis rates for flight and cabin crew. If this rate is statistically different to the rate in the broader population then it is possible to establish a prima facie link between the repeated exposure to the air and illness (cancers in particular)

What is suprising is that a union as a 'welfare' or health and safety investigation do not launch a structured plaintiff driven case to discover this data (held by airlines).

Given a balance of probability standard is a lower threshold, it is likely any well constructed law suit would never get to the court steps...

Dream Buster
2nd Mar 2018, 10:57
This recent law suit from the US demonstrates the cover up between the guilty parties - it was also a nearly new B.737.


No evidence = Huge cover up.


2nd Mar 2018, 13:06
Sigh, trying to put scientific principles to people who have already come to a conclusion is utterly, utterly, pointless. I expected better from aviation professionals.

Dream Buster
2nd Mar 2018, 19:31
Nemrytter - exactly which evidence would convince you that human exposure to toxic oil fumes in a confined space causes ill health?

Please do tell us - exactly.


Dream Buster
3rd Mar 2018, 08:31
This is not a reply - just some more evidence from hysterical professional pilots.



Dream Buster
8th Mar 2018, 20:50

1st Apr 2018, 12:31
Interesting article from 1955!


Dream Buster
4th Apr 2018, 21:06
Accident: Spirit A319 at Boston on Jul 17th 2015, fumes on board, captain died 50 days later (http://avherald.com/h?article=4b6eb830)

5th Apr 2018, 13:10
Accident: Spirit A319 at Boston on Jul 17th 2015, fumes on board, captain died 50 days later.

The video there is well worth watching.

Reluctant Bus Driver
7th Apr 2018, 13:53
Allied Pilots Association: FAA Makes Right Call on Toxic Fumes

FORT WORTH, Texas (April 6, 2018) – The Allied Pilots Association (APA) applauded the Federal Aviation Administration’s issuance of a Safety Alert for Operators (SAFO) regarding “Procedures for Addressing Odors, Smoke and/or Fumes in Flight,” citing the serious health and safety threat posed by toxic air in the cockpit and cabin of an airliner.

“We applaud the FAA for taking this significant step to mitigate the risk air crews and passengers face from toxic fumes,” said Captain Dan Carey, APA’s president. “A toxic fume event can result in immediate incapacitation and have a long-term adverse impact, and it can affect everyone on board.”

Academic research indicates that approximately 20,000 toxic fume events have occurred during the past 10 years — an average of five each day. A toxic fume event occurs when the air inside the aircraft becomes contaminated from engine bleed air.

The FAA’s recently released SAFO recommends that air carriers “review their company’s odor, smoke and/or fumes procedures to ensure they address benign odor events as well as toxic odor, smoke and/or fumes, in an expeditious manner to limit exposure of passengers and crews.”

APA has developed and submitted detailed recommendations to American Airlines concerning procedures for ensuring that crewmembers are properly trained and aware of the threat posed by toxic cockpit and cabin air. APA is now awaiting the company’s response.

“Given the seriousness of this threat, we are hopeful that the company responds promptly to our recommendations and moves forward in accordance with the FAA’s SAFO,” Carey said.

Founded in 1963, the Allied Pilots Association — the largest independent pilots union in the United States — is headquartered in Fort Worth, Texas. APA represents the 15,000 pilots of American Airlines, including several hundred pilots on full-time military leave of absence serving in the armed forces. The union’s website is AlliedPilots.org. American Airlines is the world’s largest passenger airline.

7th Apr 2018, 18:27
Is there any link to the "Academic research" that indicates approximately 20,000 toxic fume events?

7th Apr 2018, 20:15
Probably the same "research" that the avherald quotes.:ugh:

For those who have a genuine interest in understanding fume events from a scientific perspective, this speech by Richard Feynmann (http://calteches.library.caltech.edu/51/2/CargoCult.htm) is well worth keeping in mind when reading much of the academic literature.
There's huge amounts of, as Trump would put it, "fake science" surrounding fume events. To have any hope of convincing aircraft manufacturers and operators that something needs to be done this fake science needs to be put back in its box and real science take the lead. I'm sure that Dream Buster won't like me saying this, but that's life. Profit-making companies aren't going to be convinced by a bunch of papers that have a worse level of scientific understanding than a 1st year undergraduate, we'll have to do far, far, better than that.

8th Apr 2018, 10:03
A good friend, a 757/767 captain lost his licence some years ago with a definite diagnosis , by the CAA docs. of OP poisoning. I also lost my licence sometime before that, when I, too, was a 75/76 captain and had been flying a RR powered 75 which was using a little more oil than usual in the left engine, the bleed from which feeds the pack used for the flight deck air conditioning. My problem, neurological , was identified but the source / cause of my slightly abnormal eeg, in the left temporal lobe was not ? OP, who knows, but I have my suspicion.

Now long retired I fly large model aircraft powered by gas turbine engines, into the fuel for which, I use JetA1, is mixed turbine oil at 5% and is burned as total loss. The exhaust has a distinctive odour. After OP awareness I have always handled the oils with great care and avoid exhaust fumes during ground running.

However, I was recently made aware of a turbine oil called Turbonycoil 600 which does NOT contain TCP, is approved for very many full-size engines by all three of the big manufacturers for a wide range of engines including the RB211, and is , I am told, the ONLY turbine oil used by the US Navy.

So why is this oil not being used more extensively in civil aviation, removing the OP problem at a stroke?

8th Apr 2018, 11:57
I'm sorry to learn about your Medical condition.

What's the price of "Turbonycoil 600" vs Oil with TCP ?

Although "approved" by the big three manufacturers, Oil with TCP might allow a few hundreds more cycles than "Turbonycoil 600", which translates into big maintenance savings.

Money will always be driving force behind choosing between options. :suspect: (not the health and safety of crewmembers)

Zaphod Beblebrox
8th Apr 2018, 12:31
I had a toxic air incident on an a 320 a month ago. Luckily it happened at the gate prior to departure. My flight attendants had had it happen before and were familiar with the smell. We ask the passengers to deplane, called maintenance and the aircraft was taken out of service.

Maintenance found the APU oil level greatly over-serviced and oil lying in the duct-work leading from the APU air plenum. There is a duct "dry out" procedure in the maintenance manual. It's a lengthy procedure. Run the APU and air-conditioning at high temp. The aircraft was out of service overnight. There was no push-back from the company.

8th Apr 2018, 13:36
To be honest Turbonycoil 600 doesn't seem all that great either!
Safety sheet here (https://lubricants.petro-canada.com/Api/sitecore/LubesApi/DownloadResource?docID=TN600&type=MSDS&lang=en-US).
If the link doesn't work, google "Turbonycoil 600 msds".

9th Apr 2018, 10:04
What about high end, fully synthetic car engine oils?

According to this

just mineral oils, no additives, which I find almost suspicious. By the way, the English version (2013) is even less detailed than this 2017 German version.

Raffles S.A.
14th Apr 2018, 19:41
I fly a 727 and just recently we were deiced at Munchen (Munich). No problem during the flight but when we landed at base and started the APU, fumes came into the plane and made everyone's eyes burn.

Second point, there are still some airlines that insist on spraying the cabin during taxi when departing from certain countries. Surely the pesticide must have an effect on frequent travelers and crew.

Dream Buster
18th Apr 2018, 21:51
Anyone interested in Nyco oil should watch this 2007 film about toxic cabin air and find out...

Documentaries (http://www.aerotoxic.org/documentaries/)

= No evidence. :ugh::mad::eek:

19th Apr 2018, 06:16
Can anyone explain why the only evidence presented is hosted by that nut job site aerotoxic?

19th Apr 2018, 06:36
Can anyone explain why the only evidence presented is hosted by that nut job site aerotoxic?

Surely that's a rhetorical question (and don't call me Shirley :})
I find it telling that no one is taking me up on the suggestion to go start sampling air in and around airports - lots of aircraft, burning lots of Jet A and oil (most jet engines use far more oil at/near idle since they depend on pressure differential to keep the oil where it belongs) in a confined space. Unless there is an oil leak or similar mechanical failure, the bleed air at 35k is almost certainly is less contaminated...

19th Apr 2018, 15:07
tdracer - I saw a study that researched 'toxic' cabin air. Your hunch, or knowledge based leading question, is correct. Outside the airplane is much worse than the interior samples. The ramps and jet bridges had higher amounts than the cabin. You'd think rampers would be dropping like flies.

19th Apr 2018, 19:16
Forgive me if I have missed this point if already covered. It was a quick read.
I have a question as a lowly SLF.
Some time ago I read that it is advisable to aim the fresh air vent to blow straight down your face so that all breaths are of clean filtered germ free air rather than regular cabin air full of nasties, and the air flowing down your face keeps cabin air away.
The article also said that the on board filters are extremely efficient and getting air direct from the nozzle is best.
But: is it not the case that this freshly filtered air may be clean of germs etc but is still a mixture of fresh and bleed air? So the theory won't hold up.
I hope you can understand that. Not one of my best. Thanks.

19th Apr 2018, 19:37
But: is it not the case that this freshly filtered air may be clean of germs etc but is still a mixture of fresh and bleed air? So the theory won't hold up.
I hope you can understand that. Not one of my best. Thanks.
Most modern aircraft ECS systems use a ~50/50 split of 'fresh' air from the engine bleeds and 'recycled' air. That air is mixed before it gets to your overhead vent, so in that sense it's all the same. The recycled air is run through a HEPA filter, which is extremely effective at filtering out germs/viruses and similar particulate contaminates - but would be ineffective for gaseous contaminates. Your technique of trying to breath only air from the overhead vent would help prevent you from catching a cold from the person sitting next you. But if the engine bleed air is somehow contaminated it wouldn't help significantly.

20th Apr 2018, 06:11
I find it telling that no one is taking me up on the suggestion to go start sampling air in and around airportsSome of my colleagues, being scientists rather than activists, have done just that. Their results are similar to those mentioned by misd-agin: The ramp is not a pleasant place to be in terms of chemicals in the air.
One thing that surprised me from the study (not yet published, but under review now) was that smoke from aircraft tires was a strong contributor to local pollution and contained a whole array of nasty substances.

20th Apr 2018, 12:39
One thing that surprised me from the study (not yet published, but under review now) was that smoke from aircraft tires was a strong contributor to local pollution and contained a whole array of nasty substances.

A significant proportion of particulates due to road use comes from tyres and brakes, but it's fairly hard to find much detailed information about it, especially in the current vogue of blaming everything on diesel cars.

Heading possibly more off-topic, there are predictions though that the proportion could eventually reach 90%, as well as assertions that as electric cars are heavier, they may cause more of these.

10th May 2018, 22:36
Fume events, with adverse effects on crew and passengers, are gaining more attention.
I am wondering:
When they notice the fume event, can the flight crew identify the faulty engine?
Can they shut off the bleed air from that engine, or if not, are they permitted to shut that engine down?
Can either engine on its own maintain cabin pressure?
Is it their decision whether to land as soon as possible?

21st May 2018, 06:52
Handkerchiefs over noses? I think I would have felt sick too, seeing that smoke.

https://www3.nhk.or.jp/nhkworld/upld/thumbnails/en/news/20180521_19_500367_L.jpg8 passengers on ANA aircraft fall sick after smoke fills cabin

Today 04:03 pm JST
1 Comment (https://japantoday.com/category/national/8-passengers-on-ana-aircraft-fall-sick-after-smoke-fills-cabin#comments)

CHIBAOver 100 passengers on an All Nippon Airways Co flight bound for Hong Kong were evacuated from the plane at Narita airport and eight of them fell sick Monday after smoke filled the cabin, officials of the airline and the airport said.

The trouble occurred at around 9:45 a.m. on a Boeing 767 aircraft with around 140 passengers and crew on board shortly before the plane's takeoff, they said.

According to the airline known as ANA, oil from the aircraft's auxiliary power unit was sucked into the cabin through the air conditioner ducts after it had vaporized.

While the cause of the leak has still not been determined, no fire occurred, ANA said.

Dream Buster
3rd Aug 2018, 14:00

American Airline pilots now have a checklist for odors....

Dirty Sock = OIL + neurotoxic

Worth making a memory item?

:ugh: :yuk: :ok:

Dream Buster
31st Dec 2018, 07:55
Every 10 years the BBC updates it's licence fee payers with a recorded (not live, as not allowed) history lesson of whether 'so-called' Aerotoxic Syndrome (1999) exists or not?


The next hour long RADIO programme has been scheduled for 0100 on the World service on 1st January 2019 - as most Europeans are in bed, drunk from New Year celebrations, but it is due to be replayed later in the day.


For the record, here is the last BBC Panorama programme from 21st April 2008 about this cause of mass serious ill health caused by 'bleed air' in jet airliners and how a group of passengers (including children) were Aerotoxic Poisoned on 1st February 2007...


It will be most interesting to learn from the BBC exactly how the legal case of the passengers they reported ten years ago finally ended?

Happy New Year to all & many congratulations to Easyjet & Pall Aerospace for seeing the opportunity to be FIRST & make masses of money out of installing the new filters & poison detector available solutions in 2019...

Don't forget to set your alarm!! :ok:

31st Dec 2018, 08:16
Don't forget to set your alarm!!

Or stay in bed and listen at your leisure: https://www.bbc.co.uk/programmes/w172w0q34d6cs2y

Dream Buster
1st Jan 2019, 09:12
Latest BBC radio programme from 0100 1st January 2019

Any journalists wishing to know more evidence go to: BBC latest history failure on so-called Aerotoxicity 1st January 2019 (http://www.aerotoxic.org/bbc-latest-history-failure-on-so-called-aerotoxicity-1st-january-2019/)

Dream Buster
2nd Jan 2019, 21:37
Rogwk - could you contact me please & I'll fill you in.Thanks. [email protected] :ok:

2nd Jan 2019, 22:02
Dream Buster
Since you're very obviously on a crusade on this subject, would you mind addressing the points raised in posts 352 and 356?

Or are you ignoring that because it doesn't fit the narrative?

2nd Jan 2019, 22:36
The points made in those posts are irrelevant to this discussion, which concerns the effects of inhalation of toxins within aircraft due to bleed air containing the toxins being used to supply the cabin. Pollution outside the aircraft whilst maybe worthy of separate discussion is not relevant here.

2nd Jan 2019, 22:56
Last time I checked, people - including aircrew - breath around airports. Aircraft ECS systems use engine bleed air when they are on the ground and near airports. Aircraft exhaust on the ground includes significant amounts of engine lube oil (most turbine engines consume far more oil at/near idle then they do at power due to the way the lube systems work). If there is a problem with the air around airports, people - like pilots - who spend a lot of time at airports would be at risk.
If aerotoxicity is in fact an issue, how can you categorically state the issue isn't due to the air at the airport if no one is checking?

3rd Jan 2019, 03:05
Does anyone have information on environmental system contamination in Airbus aircraft after an engine compressor wash using Lufthansa cyclean techniques? The fumes are the dirty sox / oil type fumes in many cases and are giving crew headaches, disorientation, flushes, facial tingling and cognitive confusion.


Without doubt, the air around airports isn't going to be great. However, in the case of Airbus, they claim their ECS producers air quality on the tarmac due filtering at very high levels ( see Fastrack magazine references ). Oil and other contaminants pumped straight off the engine into the mixing unit is longer lasting in my experience.

3rd Jan 2019, 08:00
i’m merely stating that this thread is about toxic cabin air. External contamination is a subject worthy of discussion but should not divert the thread from it’s subject, this being toxic air [b]in the cabin.

3rd Jan 2019, 08:34
And I'm simply point out that if the air being sucked in from outside is contaminated, then the air inside will be similarly contaminated. Any meaningful analysis needs to look at the entire system. If the ECS system can't filter out contamination coming from the engine internals, then it won't be able to filter out similar contamination coming from outside the aircraft.

Look, a fume event caused by an engine oil leak is bad news for the people who are breathing the fumes. No argument. But such events are rare (especially since the most common culprit engine/aircraft are disappearing from service). Before I retired, I checked the incoming 21.3 reports at Boeing for fume events for about six months. There were a number of fume events, but only three were somehow related to the ECS system - most were galley events with the odd electrical smoke event. Of the three, one was an improper engine water wash, one was reported as an actual engine oil leak, and one was an air-cycle machine failure on a 787 (you know, the one aircraft that doesn't use engine bleed air). So fume events due to engine faults are pretty uncommon. (BTW Gnadenburg, while it certainly smells unpleasant, the stuff they use for an engine water wash is pretty benign - many use just plain water. If there is anything particularly toxic, it came from the 'dirt' that was washed off the blades, not from the cleaning solutions. If the wash is done properly the bleeds are blocked such that nothing gets into the bleed system, but sometimes mistakes are made).
What is often claimed is that 'normal' engine bleed air is a hazard - but there is little data to support that. If the infinitesimally small amounts of engine oil that finds its way into the engine bleed system from a healthy engine is a hazard, then the far higher concentrations that get sucked into the aircraft at and around the airport would constitute a hazard.

3rd Jan 2019, 13:47
Having flown types which are notorious for fumes for over 20 years and now suffering from the effects, my view is that it’s the small cumilative effects that are the main problem. Many on here will be familiar “sweaty socks” odour, often shortly after the start of descent. Evidence of such is obtainable, but little effort seems to have been expended over obtaining it.
This is not to say that toxins do not come in other ways, but in my view having experienced it daily for many years the relatively small leaks are the biggest problem.

16th Jan 2019, 16:40
Interesting video giving advice to cabin crew from their union.

Dream Buster
7th Feb 2019, 19:36
2019 Aircraft Cabin Air Conference 17/18 September 2019

The issue of contaminated air has been discussed on this forum for over a decade so I wanted to bring to your attention that the flight safety issues of contaminated air on aircraft will be discussed at the 2019 Aircraft Cabin Air Conference on 17/18 September in London. The conference will also look at the regulatory and legal aspects of this issue, the health implications and the solutions available to aircraft operators.

The 2019 Aircraft Cabin Air Conference is supported by over 30 crew unions globally and is an industry supported event sponsored by Pall Aerospace and BASF to name a few (companies offering solutions to the problem).

I attended the 2017 conference and I found the conference really helped increase my understanding of the issue.

More details at:


Dream Buster
28th Mar 2019, 19:26


Dream Buster
8th Apr 2019, 20:02
Latest High Court action in London:



Dream Buster
26th Jun 2019, 08:27
Accident: British Airways A320 near Tenerife on Jun 23rd 2019, fumes in cockpit and cabin (http://avherald.com/h?article=4c9a5bc4&opt=0)
Incident: British Airways A321 near London on Jun 23rd 2019, fumes in the cockpit (http://avherald.com/h?article=4c99bc26&opt=0)
Accident: British Airways A320 near Frankfurt on Jun 18th 2019, fumes injure passengers and cabin crew (http://avherald.com/h?article=4c95e89d&opt=0)
Incident: British Airways A321 at Sofia on Jun 15th 2019, fumes in cockpit (http://avherald.com/h?article=4c93ddeb&opt=0)
Accident: British Airways A321 near Copenhagen on Jun 8th 2019, fumes on board (http://avherald.com/h?article=4c90084d&opt=0)

Dream Buster
1st Jul 2019, 10:26
Radio: https://www.rts.ch/play/radio/on-en-parle/audio/air-toxique-dans-les-avions-les-risques-pour-les-passagers?id=10511478

TV: https://www.rts.ch/play/tv/mise-au-point/video/le-syndrome-aerotoxique?id=10544273

BBC still banned from mentioning the A word....

Dream Buster
1st Aug 2019, 09:43

and from 2017:

https://www.wsoctv.com/news/9-investigates/today-at-5-toxic-air-onboard-passenger-jets/498575431?fbclid=IwAR2Hd2nYbd2CwcV7iYWiXdzrgUeObj4vo08jpavz2 QPe_ss6xHg9wIu2Tvk

and from April 2019:


How DO they get away with it?

Dream Buster
20th Aug 2019, 21:34
'Everybody Flies' film announced https://filmindustry.network/documentary-everybody-flies-to-premiere-at-raindance-film-festival/37565?fbclid=IwAR3ANwnhPo6j1My2e3bl_3j05OBbyMMgTgBvFArO3gFt6 nD0-UGxPP_iG3Y


17th Oct 2019, 03:06
The problem does at last appear to be getting more mainstream coverage at last

21st Nov 2019, 22:45
"New Caledonia’s Aircalin returns brand new but “smelly” A330-900 to Airbus for thorough inspection"

://www.aviation24.be/airlines/aircalin/new-caledonias-aircalin-returns-brand-new-but-smelly-a330-900-to-airbus-for-thorough-inspection/amp/ (https://www.aviation24.be/airlines/aircalin/new-caledonias-aircalin-returns-brand-new-but-smelly-a330-900-to-airbus-for-thorough-inspection/amp/)

22nd Nov 2019, 06:24
The article implies that TAP never got to the bottom of the similar problems it also encountered with its A330neos earlier this year.

Does anyone have an update on that ?

Dream Buster
7th Aug 2020, 15:22
Accident: Jetblue A320 at Portland on Jan 20th 2017 and Jan 21st 2017, fumes injure captain, court confirms causal link (http://avherald.com/h?article=4daedcc8&opt=0)



11th Aug 2020, 21:45
Unfortunately the long running thread discussing this was recently moved to another section of the forum.
However there has been a very significant development in the US courts which may have far reaching effects on the industry.
Link to the case. (https://48b4ed48-471d-4786-b5ed-b7d9563b03f8.filesusr.com/ugd/3e3e4e_ef7b21e48b324c7191b4ce64cd6ee3f8.pdf)

12th Aug 2020, 08:50
More details of the case Here (https://www.change.org/p/stop-contaminated-cabin-air-in-aircraft/u/27502093?cs_tk=AohE2op_u8p-EEpsN18AAXicyyvNyQEABF8BvG1Zcfzzx_XAtq2SLqAFJY4%3D&utm_campaign=2313ba4bcb3c4830be16188a36484b0a&utm_content=initial_v0_4_0&utm_medium=email&utm_source=petition_update&utm_term=cs)
I’ll just have to accept that for whatever reason threads about this subject get moved to a quite obscure part of the forum. Considering that this is so important to the health of those in the industry and may well have a major effect on the profitability of airlines I can’t think of any other subject that is more appropriate for discussion in R & N. If I were a conspiracy theorist I’d think they’ve even nobbled pprune!

Manual Pitch Trim
24th Oct 2021, 18:53
The science and recent published reports have made a compelling case.

have a look at the researchgate article

“Ultrafine particle levels measured on board short‑haul commercial passenger jet aircraft

new study out just published

“Susan Michaelis1*  , Tristan Loraine2 and C. V. Howard3 

Abstract  Background:  Airline crew members report adverse health effects during and after inhalation exposure to engine oil fumes sourced to the air supply system onboard commercial and military aircraft. Most investigations into the causal factors of their reported symptoms focus on specific chemical contaminants in the fumes. The adverse health effects reported in aircrew exposed to the aircraft air supply, bled unfiltered off the engine or Auxiliary Power Unit (APU) may be related to particulate exposures, which are widely known to effect health. While oil contaminates the aircraft air supply, some suggest that this will only occur when there is a bearing seal failure, others document that there is low level oil contamination of the air supply during normal engine operation. This brief pilot study explores whether par-ticulate exposure may be associated with the normal engine/APU and air supply operation and to therefore increase the understanding that UFP exposures may have on crew and passengers.”

1st Apr 2022, 15:32
Finally, finally, could it be that a government might be heading towards taking the problem of toxic fumes in aircraft seriously?

The LA Times boasts an exclusive with the headline Congress is moving to curb toxic fumes on airplanes

The piece opens with The airline industry would be forced to adopt new measures to protect passengers and crew members from toxic fumes on airplanes under a bill introduced in Congress this week.

You can find the article at https://www.latimes.com/california/story/2022-03-31/congress-curb-toxic-fumes-seeping-airplane-cabins?utm_id=51843&sfmc_id=1980085

Yes, I know there’s a previous thread on this called Toxic Cabin Air - but for some unexplained reason it got shuffled off to Ground & Other Ops Forums - and now it’s hard to find at all. Surely this subject is of huge safety interest to everyone in the business - and it deserves a new thread in Rumours & News? (Please, lovely Mods…)


17th Apr 2022, 17:17
Airsound, thx for your posting.

I wasn't aware of Congress prepping a bill regarding this. Finally some recognition and progress. I am contacting the senators writing this bill because I feel it doesn't go far enough.

They can go much farther to protect airline crew than just alerting and reporting on board a flight. There needs to be a comprehensive testing program, mandated by Congress, out of reach of parties that try to keep covering this up, to establish what exactly is happening on many many flights regarding air quality on board.

Additionally it needs to be ruled an occupational disease so crews don't have to fight and go to court for years to get financial assistance.

Also Congres needs to mandate airlines to implement filters that catch those organophosphates and airplane manufactures to design new airplanes in a way that only fresh air enters the cabin, not through engines or APU, ala 787. yep that will cost money and fuel burn so you can expect a strong lobby against it. Maybe lives are more important than money ?

i lost my medical years ago due to this but wasn't aware of this issue until years later, after flying 27 years on all kinds of jets. Finally have my medical back.

21st Apr 2022, 17:42
Another case reported on yesterday https://www.change.org/p/stop-contaminated-cabin-air-in-aircraft/u/30463664?cs_tk=Ang_woPFu8p-EP5-aWIAAXicyyvNyQEABF8BvOLXY5KCuS6cQcTUZEGE6-M%3D&utm_campaign=78921bc5cec547279ab1fcefe9911c42&utm_content=initial_v0_5_0&utm_medium=email&utm_source=petition_update&utm_term=cs

Manual Pitch Trim
2nd May 2022, 11:43
Unfortunately money is more important than lives. Pall Aerospace makes Cabin Air Sensors g
Airbus knows theres a problem proven by science but they prefer to cover it up and doubt it as they have done with climate change. Boeing knows thats why they designed the 787 that way. Technology exists to improve CAQ.
have a look at the Andrews Myers settlement against Jetblue, which is a landmark case proving the aerotoxic syndrome.

The thing is low dose exposures do damage but there havent been long term low dose studies done.

it is so undersported and when reported hard for maintenance to find the source in light minor events.

if you see the GCARS APP where we need all to report even minor events in this global reporting system.

when they tell you its must a minor smell doesnt affect you, its a lie its toxic air which can be improved with advanced filters upstream of the bleed by PTI technologies and system changes.

11th May 2022, 12:39
Interesting that Gulf War syndrome has been attributed to Sarin, which contains similar chemicals to those found in superheated aircraft engine oils. It has also been revealed that susceptibility to symptoms is due to genetic differences.
Link (https://www.bbc.co.uk/news/health-61398886)

11th May 2022, 23:55
Interesting that Gulf War syndrome has been attributed to Sarin, which contains similar chemicals to those found in superheated aircraft engine oils. It has also been revealed that susceptibility to symptoms is due to genetic differences.
Link (https://www.bbc.co.uk/news/health-61398886)
did I miss the info re the chemicals?