Join the enews community - Terms
Filter by Categories

The health risks of airplane ‘fume events’

Reading time: 7 minutes

The airline industry may soon be forced to accept that toxic fumes from the engines can get into airplane cabins—and they’re causing chronic health problems for aircrew and passengers. Bryan Hubbard reports

It’s not supposed to happen, at least according to the airline industry, but there’s a growing acceptance by the World Health Organization and even the US Congress that toxic fumes can seep into airplane cabins, causing anything from nausea to long-term neurological problems in the crew and passengers.

Admittedly, the phenomenon—known as a fume event—is relatively rare, but some pessimistic estimates reckon it happens on at least 1 percent of flights. If that’s true, of the 100,000 flights taking off every day around the globe, a fume event is happening on a thousand of them.

Although fume events have been a feature of air travel since jet engines were refigured in the mid-1950s to draw cabin air from the engine, the airline industry has consistently denied they happen—and, if they do, they don’t cause any health problems—and they have recruited scientists to agree with them.

The tide is finally turning, and it’s because of the mounting number of cabin crew—and some frequent-flying passengers—who are experiencing chronic health problems. Flight attendants are in the third most hazardous profession, ahead of drill operators in the oil and gas industry, according to statistics from the US Department of Labor, which based its findings on the level of exposure to contaminants and hazardous materials.

A group of 17 aviation experts, doctors and scientists has put together a testing and treatment protocol for doctors, who are being encouraged to recognize aerotoxic syndrome (AS), the collective name for the range of problems that can happen after fume events—as an occupational illness.1

The US Congress is also being asked to recognize fume events and to vote in a range of reporting and testing procedures that American ground staff and cabin crew would have to instigate after a suspected incident. John Garamendi (D-California), who is sponsoring the bill, said, “Often, there’s a strong odor that you’re breathing something you shouldn’t. Anyone who’s been on an airplane when they start the engine knows exactly what I’m talking about.”

The air you breathe

All commercial jets other than the Boeing 787 Dreamliner push air into the cabin from a unit in the engine, but jet oils and hydraulic fluids can leak in if seals are worn or faulty. Consequently, cabin crew and passengers start breathing in organophosphates and ultrafine particles. Any ill effects usually pass quickly after the flight, but frequent exposure can cause chronic health problems, such as respiratory, heart and neurological illnesses.

A fume event—likened to the smell of gym shoes or a wet dog—is most likely to happen during takeoff and when the airplane starts to climb.

The International Fume Events Task Force, made up of 17 aviation experts, doctors, occupational health specialists, toxicologists and epidemiologists, has put together a protocol for doctors to follow when aircrew or frequent flyers report a chronic problem. It starts with recognizing the possibility that AS is the issue, then carrying out a series of tests for signs of organophosphates or volatile carbon hydrocarbons (VOCs) in the blood, and neurological challenges to assess cognitive and memory skills.

Anything from chronic fatigue or depression to loss of balance, blurred vision, headache, nervous disorders and cognitive problems, such as memory loss, can happen after a fume event.

“This has been happening for the last 70 years, and reports of air crew becoming unwell continue to rise,” said Dr Susan Michaelis, a former pilot and leader of the task force.

“When aircrew or passengers become unwell—whether they are still on the plane, suffer symptoms in the days or weeks to come, or report illness in the years that follow—there’s nothing in the medical books, there’s no guidance material for the aviation industry or medical professionals, and very often they are turned away or given minimal testing.”

Prove it

But establishing that fume events cause AS has always been the problem for those trying to get the syndrome recognized as an occupational illness, especially if health problems start happening only weeks or years afterward, as Michaelis said.

Their efforts have been downplayed by the airline industry, which has consistently tried to keep a lid on fume events. Admitting they happen and could cause chronic health problems would be bad for business, and it could leave airlines open to liability claims if it could be established that they were aware that their passengers were at risk.

“If people believed that airlines were harming people deliberately, and not taking every precaution, people wouldn’t fly with them,” said Dr Michael Bagshaw, former chief medical officer of American Airlines and one of the most vocal deniers of a direct causal link between fume events and AS.

The German Aircraft Accident Investigation Branch concluded in a 2009 report that it wasn’t being sent details of all incidents because the data was “considered proprietary by the airlines,” and several physicians said they had been approached by “industry physicians” to reconsider their AS diagnosis of a patient.

The industry has also mounted coordinated opposition to research and the testimony of pilots and flight crews. One strategy has been to deny toxic chemicals could cause illness, while another has questioned the accuracy of swab samples taken from cabin surfaces after a fume event.

The Committee on Toxicity—a branch of the UK’s Food Standards Agency—went further and claimed AS symptoms were the result of the nocebo effect. In other words, cabin crew might smell odors during the flight and then wrongly believe any health problems they experienced afterward were caused by the fumes.

The only outlier has been the World Health Organization, which concluded in a 2017 study that there was a clear link between a fume event and AS. The researchers interviewed around 200 crew members and recognized a pattern of “acute and chronic symptoms,” which included headaches, dizziness, breathing and visual problems.

The cases mount

Despite the campaign of denial, the stories from pilots and cabin crew continue to accumulate. In 2014, flight attendant Matthew Bass died suddenly after complaining of exhaustion and gut problems for six years. An autopsy discovered evidence of “chronic exposure to organophosphates.”

Cathay Pacific pilot Ben Holmes suffered convulsions and epileptic-like fits every 15 minutes after fumes entered the cockpit during a flight, and he has since suffered very poor health. Another pilot, Captain Niels Gomer, reported a similar incident, but one that affected him and the entire cabin. After a fume event, he started to feel dizzy and groggy, and many passengers had passed out, but he was able to land the plane safely.

In October 2017, three EasyJet flights were forced to make emergency landings after fume events, and a BA flight from San Francisco also had to make an emergency landing after the cabin crew, pilots and five passengers started suffering AS symptoms.

Several compensatory awards have created legal precedents that could sound the alarm bells for the airline industry. In 2020, the Oregon Workers Compensation Board ruled in favor of Captain Andrew Myers, a JetBlue pilot who suffered from neurological and visual disorders after regular exposure to low fume levels for years and to one acute event in 2017. A doctor stated that chronic and toxic fume inhalation was the cause of his disabilities.

In 2010, the New South Wales Court of Appeal awarded damages of AUD$139,000 to flight attendant Joanne Turner when she suffered respiratory problems after a fume event.

We’re convinced

The US Congress is also being asked to recognize fume events. Congress members are considering a bill that would require all ground crew and cabin crew in the US to report any suspected fume event and to be trained in the correct procedures to follow when there is an incident of smoke or fumes on board a flight.

“Our legislation takes action where the FAA (Federal Aviation Administration) and airline industry haven’t—requiring air detector and monitoring equipment, incident reporting and investigations of these events to ensure a safer travel experience for all Americans,” said Senator Richard Blumenthal (D-Connecticut), one of the bill’s sponsors in the Senate.

The senators point out that homes and offices in the US are required to have carbon monoxide detectors, and yet airlines don’t have to fit them on their planes. Flight attendants have been barred from bringing air samplers on board, frustrating attempts by Congress to assess cabin air quality as early as 2003.

A smoking plane

There are parallels between the airline industry’s view of fume events and the tobacco industry’s denial of harm caused by cigarettes—and the lesson seems to be that you can block the truth for only so long.

Medical researcher Stephen Mawdsley, who has examined the history of fume events, says science has been hijacked by industrial interests. “Debates over the recognition of AS have been shaped by the politics of science,” he writes.2

But the days of denial could be coming to an end, and airlines may soon have to warn passengers that while air travel is incredibly safe, there is still the small chance that toxic fumes could enter the cabin. If there is a fume event, protocols need to be put into place to recognize any health problems that happen as a result and then teach doctors how to treat them.

Fume event? Here’s what to do

If you fear you’ve been exposed to a fume event on a recent flight, the key is to detox—and quickly.

WDDTY editorial panelist Dr Sarah Myhill says it’s vital to raise your temperature through exercising, taking a sauna or bathing in Epsom salts to shed toxins, and then get them off the skin’s surface. A far infrared (FIR) sauna is especially effective. Portable FIR saunas are available from FIR-Real (

You should also be armed with an activated charcoal mask, which can filter out organophosphate compounds, when you fly. Contact the Aerotoxic Association for more information (

What do you think? Start a conversation over on the... WDDTY Community

  1. Env Health, 2023: 22(1): 43
  2. J Contemp Hist, 2022; 57(4): 959–74
SEP23: Smoke gets in the skies
  • Recent Posts

  • Copyright © 1989 - 2024 WDDTY
    Publishing Registered Office Address: Hill Place House, 55a High Street Wimbledon, London SW19 5BA
    Skip to content