Toxic fumes from bleed air - WSJ 09/13/25 article
Posted by Pilotmom3403@reddit | flying | View on Reddit | 82 comments
Dear Flight Crew members and Pilots - I am curious about your opinions regarding the risks of fume events aboard aircraft, as researched and documented in the Wall Street Journal article “Toxic Fumes are Leaking into Airplanes, Sickening Crews and Passengers” published September 13, 2025. I find it troubling that some aviation professionals have had disabling neurological injuries as a result. The article mentions lawsuit settlements with aircraft manufacturers, which are of course often accompanied by nondisclosure clauses. Is this an issue that is widely known about in the aviation profession and what is your personal concern level? Cumulative risk from chronic low-level exposure and the irreversible nature of the injuries are really concerning to me as a medical professional. I recommend reading the article, passengers as well as airline crew. Thanks in advance for any insight that you can share!
Full-Scarcity-3131@reddit
Sadly lost my medical twice to these events and have now left flying as a320 pilot as a result. Very nasty events and the industry must change. Happy to answer any questions via pm if required.
Pilotmom3403@reddit (OP)
I am so sorry to hear that these events caused you to have to stop flying. I wish there were more information about what causes them and how to prevent them. Thank you for your reply, it certainly confirms that they seem to be more common than is acknowledged.
Full-Scarcity-3131@reddit
Yes, they happen an awful lot more than the raw data ststes. Thing is it's a sliding scale as to how severe they are so at what point it gets reported depends on the crew. Different people have different susceptibility to these contaminants, so those who maybe less affected don't see them as a big deal and so wouldn't report more minor events. However these things are cumulative so every event should really be reported... It's the only way to accelerate change really.
i-luv2-fly-1656@reddit
It’s honestly alarming how often these “dirty sock” fume events are described as rare when clearly many of you have experienced them firsthand. The fact that there’s still limited transparency and inconsistent reporting to the FAA is frustrating — especially when exposure symptoms like headaches, confusion, and throat irritation are being brushed off as “not worth the hassle.”
It’s great to see some pilots and crews taking it into their own hands by carrying CO or air quality sensors. It’s a step toward independent verification. There's also a new tool on the market called SkyRecon (you can google it) which is a portable ads-b receiver WITH its own CO sensor.
FarCardiologist2140@reddit
Would an N95 mask help at all in this situation?
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Apprehensive_Cost937@reddit
Pretty widely known, especially for the events that get really bad.
There was recently a cabin crew member on Swiss A220 that died from a fume event, and there's that B737 MAX LRD story as well...
I wish the industry would be moving more rapidly towards bleedless aircraft after the B787, but unfortunately we'll have to wait a century or two, given the pace of innovation.
Brave-Sector-5586@reddit
I was a passenger on an A321 recently. While sitting at the gate, suddenly the cabin smelled like a fuel spill. It only lasted several minutes, but it was noxious.
antoinebk@reddit
This is very common when starting engines with a tailwind unfortunately.
antoinebk@reddit
The cabin crew member on the Swiss A220 died because he kept the smoke hood too long unfortunately. Not from the smoke/fumes.
Brambleshire@reddit
Instead Airbus would rather R&D single pilot ops I guess. While their regulators are looking at age 67 🤷♀️
wsj@reddit
Hi all - in case you haven't been able to access the article mentioned, I wanted to provide a link so you can skip the paywall and read for free: https://www.wsj.com/business/airlines/air-travel-toxic-fumes-64839d6e?st=D97LJd&mod=reddit
ifitgoesitsgood@reddit
A320 apu shuts down on a cooler night. Oil cools and settles. APU is started in the morning and not given enough time to warm up before the apu bleed is turned on. Some residual oil that hasn’t warmed up enough burns up and is vaporized in the apu bleed.
Rilex1@reddit
FCTM says to wait 3 minutes before turning on the apu bleed but this is almost never applied.
Theytookmyarcher@reddit
Airlines seem to make a big deal about fixing severe fume events but I always wonder what it is I smell and taste after doing bleed swaps (essentially changing air sources for the air conditioning and pressurization). What I really wish for is a study that looks at the composition and concentration of chemicals found in cabin/cockpit air throughout the flight and what it means for long term health. I haven't seen one that does this.
There is a reasons airlines are not chomping at the bit to do this.
SnazzyStooge@reddit
Add it to the list of sensors I really should be carrying (but don’t): - air quality monitor (and filter) - ionizing radiation monitor (and forecaster) - blood pressure / DVT monitor (and leg exerciser) - etc
RubHuge5144@reddit
A lot of crew have started flying with carbon monoxide detectors. One of my fellow crew was working a flight and they had to turn around and her entire crew tested positive for carbon monoxide poisoning.
SnazzyStooge@reddit
Battery powered?
RubHuge5144@reddit
https://a.co/d/gnp0GO6 this one is rechargeable but they have battery powered ones to if you’d like.
SnazzyStooge@reddit
Thanks!
doyouevenfly@reddit
Don’t forget whatever poison that’s sprayed in the hotels we sleep in for bugs and hopefully what ever is used to clean and bleach the sheets is ok too.
SnazzyStooge@reddit
lol, it’s either that or bedbugs, right?
21MPH21@reddit
Why not both?
Theytookmyarcher@reddit
Unfortunately I don't think normal monitors even detect this stuff
mi_pilot@reddit
I’m cheap (was a pricey last minute booking though) and was sitting in the back of a 737 Max the other day (row 30 - never again LOL), most of the flight it smelled funny, not quite like bathroom and not quite like dirty socks, definitely unpleasant. Hopefully wasn’t one of these fume events, as I don’t have spare neurons to lose! The FAs were spending a lot of time back there, I don’t know how they do it.
hypnotoad23@reddit
Spirit captain died as a result of a fume event 15 years ago. They are no joke. I’ve been fumed a few times now (320) and have to say that both company and union handle it really well.
Iplay1965jaguar@reddit
Is what you’re talking about different from the kerosene smell every time they are starting the engines?
hypnotoad23@reddit
Very
ImmortanBen@reddit
What did it smell like?
hypnotoad23@reddit
Dirty socks
SundogZeus@reddit
How has the union helped you out with this? Just curious.
hypnotoad23@reddit
They along with the company came up with the specific guidance of what you need to do at the hospital after a fume event.
SundogZeus@reddit
Thanks. Good to know.
Feathers_McGraw__@reddit
IIRC it was 2015
hypnotoad23@reddit
I wasn’t certain the year, just know it got talked about heavily in Indoc and on the line that if you smell it, don’t hesitate.
Prestigious-Ad4042@reddit
Inhale enough 100LL and your lungs will be hardened enough to survive anything a jet throws at you
554TangoAlpha@reddit
One of the many things I love about the 787.
Zero_Abides@reddit
Does 787 apu also not use bleed air to condition cabin?
554TangoAlpha@reddit
There is no bleed air. You have Cabin Air Compressors that take in outside air, compress it and send it to the Packs. Powered electronically by the engines/apu/gnd power. They’re the little door/shield things you’ll see on the side of fuselage next to wings on the ground.
Zero_Abides@reddit
That’s great, thanks
surefirepigeon@reddit
Preach. I don’t fly it but hope its bleed-less tech makes its way to the next generation of airliners.
Exotic-Sale-3003@reddit
There have been lawsuits over this issue for decades, which is why airlines are much more diligent about air quality monitoring these days. GTFs are just giving a bit of new life to what has always been a pretty scientifically dicey cause of action.
AceofdaBase@reddit
What air quality monitoring ?
Exotic-Sale-3003@reddit
https://www.easa.europa.eu/en/research-themes/cabin-air-quality
AceofdaBase@reddit
This looks like a study from 5 years ago. Is that what you call diligent monitoring? This is also only pertains to Europe.
fly_awayyy@reddit
The IAE has been the staple of fume events over the years lol
duaIinput@reddit
It mostly comes from the APU. The A320 has the genius engineering of having the APU inlet being below the actual APU itself.
When you shut down the 320 you’re supposed to wait 2 minutes from the APU AVAIL light extinguishing until shutting off the batteries. This is to let the APU do a normal shutdown sequence and scavenge oil back into the reservoir.
What do you think some people do when it’s go-home leg and you’re rushing to make a commute? They don’t wait the 2 minutes, which causes the APU to do an immediate shutdown when you turn the batteries off and doesn’t let all the oil scavenge back to the reservoir.
Mr. Mechanic does his overnight check and sees that the APU needs an oil service because it’s showing low. Fill the ol’ girl up. Only when the APU is turned on the next morning oil leaks like crazy out of it because it’s way overfilled, and finds it way down to the APU inlet…
The worst thing is it’s not immediate. It may be 2 or 10 flights downline, but eventually the oil is heated in the packs and causes the toxic components to be introduced to the air; a fume event.
andrewrbat@reddit
The a220 also has this exact same issue though it causes different symptoms. We used to be able to shit off the batteries as soon as the apu door was closed. When you shut off the apu with the apu still spinning at a few rpm it holds oil and the de-oil valve is kept closed . Then when you start it the next morning some of the oil hasn’t hit the sump and it throws anAPU fault and wont start. LOTS of mel’ed apus because of this…. Now we wait for the apu to spool allll the way to zero.
Yet to see a fume event due to it as i think mtc cant see oil qty on the apu without opening the tail cone. It doesn’t show the actual quantity when the apu is off. Or on. Just “norm” or a fault but not until you turn the apu knob on and energize its fadec, iirc.
EineBeBoP@reddit
As a 220 MX this is incorrect.
I turn off the batt as soon as apu is running as it gets it's required dc power from the electric TRs and not batteries. In fact it's the only plane in my fleet that doesn't require batteries on for apu.
The shutdown sequence is automatic with or without batteries.
Also the inlet is above on the 220.
And the oil level is on the status synoptic page, same as you see. We do have cards to check the sight glass occasionally, but 95% of the time we are using the electric indication.
andrewrbat@reddit
Then our overnight crews and some pilots at certain outstations just did it wrong all the time i guess. Because they put out a whole pub on how not turning off the batteries before the rpm hit 0 would prevent 80% (or something) of our apu “failures”. Or since the syn page just says “norm” i guess it’s not super helpful for servicing. I get that the trs will feed the apu when they are powered but when starting up or shutting down some times you are feeding the apu only from the batteries. At first or as the last step on shutdown. Thats mostly what this advice was regarding, shutdown. Once you have the apu selected to off and the gpu off they wanted us to wait to 0% to kill the batteries as it was the only thing left powering the plane and therefore leaving the apu de oiling shutoff valve open.
duaIinput@reddit
Very interesting, I know on the A320 (and I’m guessing most Airbusses and fuck, most modern planes) the APU oil level can only be found in the maintenance menu of the MCDU.
RavenholdIV@reddit
Is that what happens? Very interesting! The AGT1500 has a 2 minute cool down as well before shutting down.
duaIinput@reddit
It can happen for other reasons too but that’s why it’s a lot more common on the A320.
Mike93747743@reddit
Very well known on the A320. “Dirty sock” events happen several times a year.
surefirepigeon@reddit
Dirty sock smell 3 times over 2 years / 600 block in 737. It’s not exclusive to Airbus, although it does seem more common anecdotally.
SimpleObserver1025@reddit
From the WSJ article the OP referred to:
Airbus is moving the inlet to another part of the aircraft which would reduce incidents by up to 85%. The problem is that it would only be on aircraft produced beginning 2026. No realistic way for any aircraft OEM, Airbus or Boeing, to retroactively move the inlet on existing planes.
RubHuge5144@reddit
Flight attendant here. I just suffered an air conditioner quality event back in June. I suffered a multitude of neurological symptoms including severe headache, a metallic taste in my mouth, an ache in the back of my throat, the chills, my eyes were irritated and I was mentally impaired (my roommates thought I was drunk and I could recall words or even remember own address) The telehealth company that my airline contracts with to treat us if we get sick while flying told me it “wasn’t worth the hassle to go to the ER” so I didn’t go until two days later when I was getting worse and worse. I had applied for workers comp because I was missing work day and the workers comp adjuster told me that “they deny all air quality events because you can’t prove that your symptoms came from the plane”. The next day I found out that the plane I was on when the event happened had had FIVE air quality events in the last six weeks. This article says that these events are rare….5events in six weeks on one plane is not rare. There are a bunch of open OSHA complaints right now for these types of events because flight attendants are getting disciplinary attendance for missing work for these events. Which discourages people from reporting them. It’s is terrible and makes me sick what they are getting away with.
duaIinput@reddit
Have you talked to your union? They should definitely have more resources about this.
Funnily enough, other than noise and something else I can’t remember OSHA weirdly doesn’t protect pilots and flight attendants. OSHA has a memorandum of understanding with the FAA regarding health issues, so it’s really their thing to deal with which yeah… good luck.
RubHuge5144@reddit
I have been working closely with my union. There are specific whistleblower complaints that are directly related to the FAA and OSHA. When you file an OSHA whistleblower complaint against a company in the aviation industry it automatically filed a complaint with the FAA as well. It’s a long daunting process but if we don’t at least try then nothing will change.
duaIinput@reddit
Good just making sure, thank you and sorry you have to go through this.
AceofdaBase@reddit
Flight crew are carved out of OSHA protections because of the RLA. If OSHA protected us like other worker groups, we’d be considered radiation workers.
Ashamed-Charge5309@reddit
Are you doing better now?
Thanks for sharing that link. Was amusing looking up two southwest planes now in the great big wrecking yard in the sky
RubHuge5144@reddit
I still get headaches most days that I fly. I had to go back to work because my workers comp was denied and I can’t afford to not work. It’s such a hard spot to be in. I’ve been thinking of going to see a neurologist but it’ll be on my own dime.
Ashamed-Charge5309@reddit
Do you have others to band together with that may have had the same issues, or on the same aircraft? What about your union (if you have one) can they do anything?
Pilotmom3403@reddit (OP)
I am so sorry you are experiencing all that. Thank you for sharing your story. I hope improvement comes with time and maybe other commenters can provide helpful advice. Sounds like these events are indeed more common than acknowledged.
T271@reddit
Can see Reddit threads from 10 years ago where folks were very dismissive of the concept, now people seem a lot more willing to talk about it and there appears to be some professional research on it. More research can probably be done but it definitely seems like an issue.
AceofdaBase@reddit
You go to the ER and ask for an organophosphate lab panel
AceofdaBase@reddit
https://toxiccabinair.com/health-and-resources/for-healthcare-providers/
AceofdaBase@reddit
https://toxicfreeairlines.com/wp-content/uploads/2020/04/medicalprotocolforhcp2008.pdf
Torvaldicus_Unknown@reddit
Do you guys ever put on masks earlier than the QRH recommends if you suspect an event?
Baystate411@reddit
It's an immediate action step. As soon as you recognize a fine event it's masks on.
surefirepigeon@reddit
Every time I’ve donned O2 mask in response to a dirty sock smell the captains look at me dumbfounded and don’t put theirs on.
Apprehensive_Cost937@reddit
Any fumes or smoke in the cockpit = mask on first, establish communication, then call for the checklist.
oranges1cle@reddit
Does this happen on the CRJ?
AceofdaBase@reddit
Yes and on the embraer 170 also
surefirepigeon@reddit
Any aircraft that supplies packs with bleed air. So yes, and every other airliner except 787.
Professional_Read413@reddit
Wow I had never even heard of this
DwayneHerbertCamacho@reddit
Doesn’t even have to be a “fume event”. The bearings on the compressor side of the turbine in both APU & engines leak oil. Very small amounts but it’s always doing it. That oil vapor is being pumped directly into the cabin/cockpit, it may be very small amounts but it’s enough to cause neurological or other health problems over many years, even if you don’t experience a full blown fume event. Turbine oil fumes are super toxic and you are breathing it in with every breath whether you know it or not.
It’s probably right in line with the risk of skin cancer from the time pilots spend at altitude where they are exposed to elevated levels of radiation. You’re not going to notice effects over 5-10 years but 20-30+ years and it’s no surprise when you are growing tumors on your arms/face.
ndem763@reddit
Gift link if anyone wants it: https://www.wsj.com/business/airlines/air-travel-toxic-fumes-64839d6e?st=ukhLdT&reflink=desktopwebshare_permalink
rFlyingTower@reddit
This is a copy of the original post body for posterity:
Dear Flight Crew members and Pilots - I am curious about your opinions regarding the risks of fume events aboard aircraft, as researched and documented in the Wall Street Journal article “Toxic Fumes are Leaking into Airplanes, Sickening Crews and Passengers” published September 13, 2025. I find it troubling that some aviation professionals have had disabling neurological injuries as a result. The article mentions lawsuit settlements with aircraft manufacturers, which are of course often accompanied by nondisclosure clauses. Is this an issue that is widely known about in the aviation profession and what is your personal concern level? Cumulative risk from chronic low-level exposure and the irreversible nature of the injuries are really concerning to me as a medical professional. I recommend reading the article, passengers as well as airline crew. Thanks in advance for any insight that you can share!
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