“Asbestos of the Sky” – The Aviation Industry’s Darkest Coverup

The aviation industry proudly claims that air travel is “the safest way to travel.

” However, this narrative conceals a longstanding and disturbing truth: since its inception, the industry has exposed both passengers and crew to toxic air due to fundamentally flawed aircraft design—placing profit above human safety.

In flight, every passenger and crew member depends on a consistent air supply. The common assumption is that this air is either fresh or at least adequately filtered. You may have sensed—then quickly dismissed—that there could be issues with cabin air quality. But the problem goes far deeper than occasional lapses in quality control. Alarmingly, it is not accidental, but systemicbuilt into the very design of modern aircraft.

Even more concerning is the fact that the aviation industry has been aware of this entirely preventable health hazard for half a century. Despite this knowledge, it has taken no meaningful steps to filter out the cocktail of hundreds of airborne chemicals—including organophosphates, which are in the same class as toxic nerve agents like Sarin—before they are inhaled by unsuspecting travelers. Nor has the root cause of the issueunsafe aircraft engineering and the systemic deprioritization of passenger safety—been adequately addressed.

A Hidden Hazard: The History of Cabin Air Supply

The core issue stems from how modern jet airliners supply air at cruising altitudes. To maintain pressurized and warm cabin conditions, virtually all commercial aircraft since 1963 have used a method called “bleed air”—air taken directly from the compressor section of jet engines.

In the 1950s, engineers designed aircraft that drew fresh, filtered air from outside the plane. However, this safer method was abandoned in favor of cost-cutting measures. The decision-makers deemed the engineering changes too expensive to implement. As a result, the aviation industry adopted and standardized a design that would expose every crew member and passenger to potentially contaminated air—by design, not accident.1

What You’re Breathing: A Toxic Mix of Airborne Chemicals

Today, the air you breathe on board consists of a 50/50 blend of recirculated cabin air and bleed air. While the recirculated portion may be filtered, the bleed air is not—and it can contain a wide spectrum of synthetic and neurotoxic chemicals, including:

  • Tricresyl phosphate (TCP or TOCP) — an organophosphate linked to severe neurological damage.

The World Health Organization sounded the alarm as early as 1990, stating:

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

Flying the Toxic Skies: A Daily Global Risk

The only commercial aircraft that does not use bleed air is the Boeing 787 Dreamliner, which employs electrically powered compressors to bring in outside, non-engine-derived air. Unfortunately, Boeing 787s make up less than 5% of global commercial flights.

With approximately 100,000 flights occurring daily worldwide, and estimates suggesting that at least 1 in every 100 flights experiences a significant “fume event”, this means millions of passengers and crew are being exposed dailyto toxic air—often without their knowledge.

The Bleed Air Problem: Expert Insight from the Aerotoxic Association

Organizations like the Aerotoxic Association have been tirelessly working to expose the dangers of cabin air contamination. They explain:

“Bleed air comes from the compressor section of the jet engine, which has to be lubricated. Jet engines mostly have ‘wet seals’ to keep the oil and air apart, which cannot be 100% effective… These seals wear out over time or may fail suddenly, allowing significant amounts of oil to enter the hot compressed bleed air, resulting in fumes or smoke entering the cabin—a situation known as a ‘fume event.’”

Importantly, they add:

“There are no filters in the bleed air supply to stop this from happening.”

Jet engine oil is no ordinary lubricant. It’s made from synthetic chemicals, specifically designed to withstand extreme temperatures. These oils:

  • Are not petroleum-based
  • Contain organophosphates and aromatic hydrocarbons
  • Can become chemically altered (pyrolyzed) at high temperatures, forming even more toxic byproducts

Watch & Learn: The Truth About Aerotoxic Syndrome

▶️ Watch the teaser for the documentary
Unfiltered Breathed In – The Truth About Aerotoxic Syndrome

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A Complex Toxicological Assault at 35,000 Feet

Since at least 1977, when a C-130 Hercules navigator became incapacitated after inhaling contaminated cabin air, the aviation industry has quietly concealed a devastating truth: commercial flight exposes passengers and crew to a toxicological cocktail that extends far beyond what the public has been led to believe.

One major factor working in the industry’s favor is the widespread assumption that the fatigue, malaise, brain fog, and general discomfort experienced after flying is simply “jet lag”—a benign consequence of circadian rhythm disruption (medically known as desynchronosis). This explanation conveniently ignores the metaphorical 800-pound gorilla in the cabin: chronic and acute exposure to neurotoxic organophosphates and other chemicals circulating in the air.

More Than Jet Lag: The Overlooked Contributors to In-Flight Toxicity

To be clear, natural stressors such as:

  • Cosmic radiation
  • Dehydration
  • Cabin pressure levels equivalent to 6,000–8,000 feet (resulting in low oxygen availability)

do contribute to passenger discomfort and physiological stress. But what’s conspicuously absent from mainstream discourse is the role of chemical exposure—and more importantly, the toxic synergy between these various stressors.

Consider the routine use of pesticides sprayed within cabins, the bleed air infused with pyrolyzed jet engine oil, and the mix of hydrocarbons, organophosphates, and synthetic additives. Together, they form what scientists might call a “toxic soup”—a multidimensional assault on the body that can no longer be dismissed as coincidental or harmless.

And yet, when passengers feel disoriented, fatigued, or cognitively impaired after a flight, the prevailing explanation remains remarkably simplistic: “jet lag.” This term has become a convenient catch-all diagnosis, suggesting that our internal clocks are merely out of sync due to time zone shifts. While circadian rhythm disruption (desynchronosis) is a real phenomenon, it fails to explain the depth and range of symptoms commonly experienced after flying.

In reality, many symptoms traditionally attributed to jet lag—brain fog, nausea, dizziness, irritability, lightheadedness, chest tightness, and immune suppressionstrongly mirror the effects of low-level chemical exposure, particularly to organophosphates like TCP and decomposed synthetic oils. These exposures are neither rare nor incidental; they are built into the architecture of modern aviation.

The aviation industry has silently benefited from this public misconception. By blaming the body’s internal rhythms, the industry successfully deflects scrutiny away from its own engineering failures, avoiding accountability for a mounting public health issue.

It’s time to redefine “jet lag” not as a benign travel inconvenience, but as a potential signal of exposure to airborne toxins. What travelers dismiss as minor post-flight fatigue may actually be a neurological warning sign—a reaction to a chemically compromised environment that is not being addressed or disclosed.

Crew Health: The Canary in the Cabin

Airline crew, who fly regularly and remain exposed for prolonged periods, often suffer from poor and unexplained health outcomes. This makes them the proverbial canaries in the cabin. The implications of acknowledging these links are staggering. Should the industry admit fault, the resulting legal and financial liabilities—particularly in relation to crew health—would be catastrophic. The cover-up, therefore, appears to be not only strategic, but essential for the preservation of an entire economic model.


What Is Aerotoxic Syndrome?

In October 2000, a groundbreaking paper titled Aerotoxic Syndrome: Adverse Health Effects Following Exposure to Jet Oil Mist During Commercial Flights” by Dr. Harry HoffmanProfessor Chris Winder, and Jean Christophe Balouet, Ph.D., officially introduced Aerotoxic Syndrome as a novel occupational health condition.

The study presented 10 case reports of airline crew members who experienced “fume events”—episodes of visible or invisible contamination in the cabin air—and subsequently suffered significant health issues.

Acute (Short-Term) Symptoms:

Following a single fume event or short-term exposure, affected individuals reported:

  • Blurred or tunnel vision
  • Disorientation and memory impairment
  • Shaking, tremors, and seizures
  • Nausea, vomiting, and paresthesias
  • Loss of balance, vertigo, and unconsciousness
  • Headache, lightheadedness, confusion, and intoxication-like symptoms
  • Breathing difficulties, chest tightness, and respiratory failure
  • Rapid heartbeat (tachycardia), palpitations, and nystagmus
  • Irritation of the eyes, nose, and upper airways

Chronic (Long-Term or Repeated) Symptoms:

From prolonged low-level exposure—or as lingering effects from short-term exposure—symptoms may include:

  • Memory loss, poor coordination, and chronic nausea
  • Diarrhea, respiratory distress, and chest pain
  • Severe headaches, dizziness, and cognitive dysfunction
  • Weakness, chronic fatigue, and exhaustion
  • Numbness in limbs, lips, or fingers
  • Joint and muscle pain, hot flashes, and skin rashes or blisters
  • Eye, nose, and airway irritation
  • Signs of immune suppression and hair loss
  • Chemical sensitivity or Multiple Chemical Sensitivity (MCS)

A Silent Assault on the Nervous and Immune Systems

If these symptoms are indeed linked to exposure to contaminated bleed air, the implications are profound. We are looking at chemical agents capable of damaging not just the nervous system but also the immune, respiratory, and endocrine systems.

The continued dismissal or obscuring of this public health crisis speaks volumes. And yet, the evidence—biological, chemical, and testimonial—continues to mount.

A 40-Year Cover-Up—Now Exposed

Despite decades of evidence, the aviation industry continues to downplay and dismiss a serious public health crisis. Consider this: pilots, who are chronically exposed to jet engine fumes, have had jet engine chemicals detected in their blood. Yet the industry still lacks any credible justification for ignoring the problem.

Compromising the neurological fitness of pilots should be treated with the same gravity as a mechanical defect—both threaten lives. After all, pilots are the ultimate safety system keeping aircraft in the sky.

Fume Events Are Not Rare—They’re Systemic

2007 report by the UK Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) acknowledged that fume events occur on at least 1 in every 100 flights.

But the Aerotoxic Association suggests the true number may be much higher:

“On some aircraft types, crews report fumes on every flight. And since there’s no standardized definition of a ‘fume event,’ it’s impossible to give a definitive figure.”

The industry’s ability to hide these numbers is made easier by severe underreporting. Modern aircraft are not equipped with chemical sensors, and only visible smoke triggers an entry in the flight log. In many cases, crew members’ noses are the only detection mechanism—hardly reliable given that the most toxic chemical present, tricresyl phosphate (TOCP), is entirely odorless.

As U.S. aviation attorney Alisa Brodkowitz once poignantly observed:

“The only thing filtering this toxic soup out of the cabin are the lungs of the passengers and crew.”

Internal Boeing Documents Confirm the Crisis

In 2007, 60 Minutes obtained an internal Boeing memo that confirmed the company was aware of the issue. A senior Boeing inspector wrote:

“Some of the events have been significant, in that the crew reported blue smoke with defined waves.”

“Who knows what the by-products are in hot synthetic turbine oil? The data sheet has warnings about breathing the fumes.”

60 Minutes highlighted the most chilling line in the memo:

“It may take a tombstone before a solution is adopted.”

That tombstone came in the form of Richard Westgate, a British Airways pilot who died at age 43 after repeated exposure to fume events. And he is likely not the only casualty. [NOTE: This 60 Minutes episode has now been scrubbed from the internet.]

There Is a Solution—And It Already Exists

The only major exception is the Boeing 787 Dreamliner, a long-haul aircraft designed with electrically powered compressors that bypass the bleed air system entirely, pulling clean air from outside the fuselage.

And yet, Boeing does not promote this clean-air design, likely to avoid drawing attention to the toxic legacy of its other models. Still, in 2014, the Global Cabin Air Quality Executive (GCAQE), representing over 800,000 airline staff and consumers, praised Boeing:

“Only the Boeing 787 provides passengers and crews with clean breathing air.”

The 787’s very existence confirms the industry knows the problem is real. Its clean-air system is a quiet admission of the toxic status quo—a first step toward systemic change.

See more here Substack

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Comments (2)

  • Avatar

    D. Boss

    |

    Bah, a chicken little screaming the sky is falling. Many points this article is either ignorant of factors, or outright exaggerating by many orders of magnitude. First off the “Plastic Princess” or the B787 (because she’s almost all plastic, or composite instead of aluminum) not only does not use bleed air, but then needs to have 10x more electrical generating capacity to perform the functions of bleed air, which normally includes starting the engines with bleed air from the APU or a ground compressor. And she uses electrical brakes instead of hydraulic ones which is unrelated to bleed air, but demonstrates the MAIN reason she is designed so stupidly – to be seen as going GREEN. Eliminating bleed air saves fuel, So almost all of these “innovations” are woke attempts to go green and cowtow to the alarmist agenda. (but really how much fuel is saved when you need electrical generators 10x larger than if you used the bleed air???)

    Boeing going away from bleed air had nothing to do with so called clean air in the cabin.

    Next is the reality of how much lubricant leakage occurs into the bleed air. The linked PDF has a guesstimate and it shows that normal leakage into the bleed air is 2% of 0.3 liters per hour of oil consumption. That equates to 6 milliliters of oil per HOUR.

    https://www.fzt.haw-hamburg.de/pers/Scholz/Aero/AERO_M_JetEngineBearingsAndOilConsumption_18-04-02.pdf

    Now at cruise power, the CFM-56 engine which powers 60+% of aircraft (B737, and A320 families) generates 18,300 cubic meters per hour of bleed air. Thus the oil concentration in the bleed air is 0.328 parts per billion by volume.

    (why is there so much bleed air needed? Because airplanes are not sealed vessels, they leak all over the place, and have at least 2 massive “outflow valves” on the exterior of the fuselage, being about 6 x 8 inches with a variable door opening to manage the cabin pressurization. That is to say these outflow valves are continuously letting air out of the plane to maintain the desired cabin pressure whilst the bleed air system is pumping air into the cabin)

    And oil consumption (which via the dry sump system the 98% majority is dumped overboard from the engine) is closely monitored at every ground stop, and oil added to the reservoirs of the engines. If the consumption rises, the engine/plane is taken out of service and the leak is rectified.

    Bleed air is used not just for cabin pressurization and air conditioning, but for pressurizing the oil sumps, anti icing of the wings and engine cowlings, among other things. All of which have to have additional electrically powered systems in the Plastic Princess which is grossly inefficient, and adds considerably complexity and points of potential failure.

    And the cabin air is roughly 50% recirculated through filters – so if there was a real contamination problem as this article asserts, those filters would need changing very often which they do not.

    I’m not saying the article’s core information is wrong, there likely is some blow by of the oil into the bleed air stream, at 250-450 deg C which likely cannot cause pyrolizing as the oil is designed for even higher temps in the bearings. But the concentration in the cabin air is normally a fraction of a part per billion. (this high temp of raw bleed air is why it is piped into the leading edge of the wings for anti ice, and around the engine cowlings to prevent ice formation at the inlets, and it passes through the air conditioning packs to be cooled and then into the cabin to maintain breathable pressures, and it provides various important functions in the operation of the engine as well, such as pressurizing the dry oil sump system for the bearings, among other things)

    The utility of using bleed air for critical functions in airliners outweighs any extremely minor irritation of teensy amounts of oil getting into the cabin air.

    In closing the examples the article cites of a pilot death and crew’s having heath issues due to bleed air contamination, are the result of poor/bad maintenance not an inherent design flaw of utilizing bleed air. If the correct protocols were followed, those incidents of excessive bleed air contamination would have been rectified before health problems arose.

    Reply

  • Avatar

    Wilson Sy

    |

    You speculate on how much bleed air leakage based on an engineer designer’s “guesstimate”. This is not science. We need proper scientific study of cabin air quality, given the adverse evidence. You concluded that it is “not a inherent design flaw of utilizing bleed air” by assuming correct protocols were not followed, without providing evidence. Safety should not rely on perfect practice.

    Reply

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