Of course crossing time zones can cause “jet lag” and take a few days to adjust. But the same feelings can be produced on short-haul flights which experience what is known as a “fume event”; the insidious problem of toxic oil fumes leaking into aircraft cabins which can cause severe long-term damage to thehealth of both passengers and flight crews, according to Captain John Hoyte who wrote an article for Nexus Magazine.
In June, 2010 the U.S. Senate approved an amendment by Senator Dianne Feinstein (D-Calif.) that required the FAA to conduct a study of the air quality in the cabins of all U.S. airliners to determine the level of toxicity to crews and passengers.
Aerotoxic Syndrome, is a term coined in 1999 by Dr. Harry Hoffman, Professor Chris Winder and Jean Christophe Balouet, Ph.D. and is the name given to the illness caused by the long term effects of breathing contaminated cabin air in an aircraft.
“Fume Events” in which cabin air is contaminated, occur in 1 in 2000 flights according to a United Kingdom government website, while other reports claim 1 in 100 flights is a more accurate figure.
Flight crews on certain aircraft report experiencing some fumes to a degree on nearly every flight.
“Bleed Air” is warm compressed air supplied directly from the engine which is used to obtain a comfortable environment and sufficient air pressure at high altitudes for proper breathing. Bleed air is mixed inside the aircraft in a 50/50 ratio with re-circulated cabin air.
The following contains Nexus Magazine excerpts from their Feb-March 2010 article titled:
BEST KEPT SECRET IN AVIATION: AEROTOXIC SYNDROME with full credit and attribution to be given to both Captain Hoyte and Nexus Magazine.com. where noted.
Captain John Hoyt, a former commercial airline pilot, is the Chairman of the Aerotoxic Association, a support group for sufferers of Aerotoxic Syndrome.
Captain Hoyt writes of his experience as a BAe 146 pilot in the Nexus article:
I enjoyed extremely good health until 1989…I suddenly developed Alzheimer’s type symptoms of failing memory, speech difficulties and trouble with thought processing which left me feeling permanently intoxicated. As I was on permanent night flying duties, I logically put these symptoms down to the anti-social hours and I kept quiet for fear of losing my job…By 2005 by which time I had become a Training Captain on the BAe 146 but was now day flying, my memory was appalling and I knew that I was a hazard not only to myself, but to my passengers. In August 2004, I had “failed safe” by walking off a BAe 146 just prior to take-off for a difficult approach into Salzburg airport, Austria, as I was convinced that I was about to kill not only myself but all of my passengers. I finally stopped flying in early 2006 at 49 years of age, confused as to how my excellent health had progressively failed over a 16 year period, leaving me a “zombie-like vegetable”. I would be diagnosed by aviation specialist doctors in early 2006 as suffering from “chronic stress”, but 12 months later I knew without any doubt whatsoever that I had actually been “chronically poisoned” by repeatedly breathing oil fumes in the BAe 146. Like so many others around the world, I would unfortunately discover “the best kept secret in aviation” and a major cause of mysterious, undiagnosed ill health, mainly in aircrew but also in airline passengers who can become equally adversely affected from just one bad flight. (Captain John Hoyte/Nexus Magazine.com article)
Senator Feinsteins’ amendment was included in the FAA’s $17 billion dollar Transportation Modernization and Safety Improvement Act and required the FAA to complete a study of cabin air quality within one year. According to Feinstein’s statement entered onto the Congressional Record: The amendment was designed to ensure the FAA has the necessary information to protect the American public from exposure to harmful contaminants while flying. The amendment also provided the FAA with the authority to mandate that airlines allow air quality monitoring on their aircraft for the purposes of the study.
EXPOSURE IS A ‘SERIOUS MATTER”
Senator Feinstein calls exposure to the “toxic soup” of contaminated air that contains carbon monoxide gas as well as chemicals that can damage your nervous system called tricresylphosphates (TCP’s) “a very serious matter”.
Exposure to TCP’s can initially cause stomach ache and muscle weakness followed by delayed memory loss, tremors, confusion and other symptoms, according to Feinstein’s testimony for the Congressional Record. Nickel, Cadmium and Beryllium are also in the jet engine oil and have been found in the blood
of pilots and crew members tested after exposure to fume events, according to the Aerotoxic Association website.
Mobil Jet Oil II (made by Mobil Oil Corp), according to the Material Safety Data Bulletin (MSDS)- contained on the Aviation Organophosphate Information Site, has Tricresylphosphate (TCP) listed as one of its ingredients. In the hazards identification section it states:
Overexposure to TCP by swallowing, prolonged or repeated breathing of oil mist, or prolonged or repeated skin contact may produce nervous sytem disorders including gastrointestinal disturbances, numbness, muscular cramps, weakness and paralysis. Paralysis may be delayed.
As far back as 2004 “The FAA concluded that the problem was so “unsafe” that it called for repetitive detailed inspections of the inside of each air conditioning duct to prevent impairment of the operational skills and abilities of the flight crew caused by the inhalation of agents released from oil or breakdown products, which could result in reduced controllability of the airplane.”, according to Senator Feinstein.
Yet to date no action action to change has occurred.
A DANGEROUS DESIGN FLAW IS THE CAUSE
According to Captain Hoyte as stated in the Nexus Magazine article, the problem began in the early 1960’s.Prior to then, engineers provided compressed air in high altitudes to support breathing, by designing mechanical compressors that did the job well. All of the early jet airliners such as the DC-8 and Boeing 707 used this separately compressed air. In the early 1960’s the “bean counters” looked for cheaper and simpler ways to provide that air. All jet engines have vast amounts of compressed air available from the forward section of the engine, before the fuel is added and burned. Soon the engineers would take this hot engine air and pipe it into the cabin. They would call it “bleed air” as it was “bled off” the jet engine compressor section. Despite the fact that many engineers warned if the “bleed air” should become contaminated with oil from within the engine or hydraulic fluid, then everyone in the plane would be breathing a contaminated mixture of air and oil, this new method was accepted and incorporated into new aircraft. The risks were calculated as negligible versus the financial savings and every aircraft from that period forward, including turboprop planes use the bleed air system to get compressed air into the cabin…even AIRFORCE ONE. (Hoyte/Nexus)
In March 2009, the President of The American Society of Heating,
Refrigeration and Air-Conditioning Engineers (ASHRAE) requested the FAA “investigate and determine the requirements for bleed air contaminant monitoring and solutions to prevent bleed air contamination”, according to Senator Feinstein who also noted that in 2007 ASHRAE developed voluntary model standards to protect air craft cabin air quality.
Only the new Boeing 787-8 Dreamliner has gone back to the independent heating system so the air is no longer circulated from the engine through the cabin. This is probably thanks to Senator Diane Feinsteins efforts and her legislation that demanded the FAA take a closer look at this serious problem in 2010.
Captain Hoyte tells of the history of the problem in the Nexus article:
The first bleed air jets were the Boeing 727 and the McDonnell Douglas DC-9, but it would be 36 years before Boeing would suddenly decide in 1999, not to use bleed air in future designs.It would build a new type of jet: the Boeing 787 Dreamliner.The jet would be made of a completely composite materials and have a relatively high cabin pressure. But Boeing would never be able to admit that it had ditched bleed air, as it continued to build bleed-air aircraft. Obviously it would take many years for a complete change of technology… Since 1963, there has been an ongoing debate as to how clean the bleed air is. Boeing itself admits that in abnormal situations, mainly when oil seals “rarely “ fail, the engine oil can contaminate the air. This leads to the claim that the air is “generally safe in normal operations”. But what about abnormal operations: the every-other-day-occasions? What Boeing does not acknowledge readily is that oil seals do not always fail suddenly but often fail slowly over many hours, leaking oil into the air. The fact is that the bleed air and oil are allowed to mix due to: a basic design feature which deliberately allows small amounts of oil to pass through oil seals to provide lubrication...the fact that jet engine oil seals prefer a constant temperature environment to perform “normally” and tend to leak when warming up or cooling down...the fact that when power changes are made, such as on take off or descent when an incredible number of revolutions are suddenly increased or decreased, there are differing tolerances within the jet and the potential for oil to leak. There are a number of basic facts which now must be presented. There will always be a few minor differences, but the following facts are known: Aircrew and passengers generally breathe the same air; if the pilot is sick, so will the passengers be sick. All jet aircraft use bleed air: turbo props, Air Force One, corporate jets. The chemicals in the jet engine are extremely toxic, especially since an organophosphate (OP) is added to make engines last longer and provide fire-retardant properties. So what are organophosphate chemicals? They were developed during World War II by the Germans, specifically to do harm to human nervous systems. They have since been used in pesticides e.g. sheep dip-hence the dreadful nuerological illnesses affecting many sheep farmers in the UK during the 1980’s and 1990’s. Gulf War military personnel were also exposed to OPs and became mysteriously ill. It is known that chronic exposure to Ops can go on to change personalities and character and affect relationships and moods and devastate lives. Does any of this sound familiar? (Hoyte/Nexus)
How prevalent is this problem how long has it been known and what can be done about it?
“Breathing organophosphate fumes in a confined space is more hazardous than breathing in tobacco smoke and scientists agree that a cocktail of chemicals working together synergistically is collectively many times more dangerous than any chemical in isolation,” according to Captain Hoyte. The UK Mandatory Occurrence Reporting Scheme for June and July 2009 shows a fume event being recorded on average every second day or approximately 18,000 passengers per year being exposed to toxic chemicals It has also been suggested that only around 4% of fume events are reported. University College London calculated in 2006 that 196,000 UK passengers are exposed to toxic gas each year. The UK Committee on Toxicity citing pilot reports contradicts the government findings that “fume events” occur in one in 2,000 flights, they say it is closer to one in 100 flights. (Hoyte/Nexus)
Neurotoxic properties of organophosphates have been known since before WW II, but according to the Aerotoxic Association website the first well-documented case is a C-130 Hercules navigator becoming incapacitated after breathing contaminated cabin air in 1977.
There are several viable solutions to this problem which probably won’t be realized until the problem is addressed as the true menace to the health of those who fly that it is. Frequent fliers should be the most alarmed, but also pregnant women, very young babies and any persons with breathing issues are also at greatest risk.
In November, 2009 a French Company, NYCO S.A., which manufactures aviation lubricants and more (specifically aviation jet engine oils in its plant in Tournai, Belgium) sent a letter regarding the Potential Toxicity of Jet Engine Oils to the European Aviation Safety Agency Rule Making and Product Safety Secretariat. NYCO has a long distinguished history in the field of military aviation oils having developed the engine oil for the Dassault “Mirage” fighter.
In 2006, according to the letter:
NYCO became aware of the possibility of contamination of bleed air by engine oil vapours, in case of mechanical deterioration of the seals of the APU or propulsion engines, this bleed air being used for the conditioning of cabin air on commercial aircraft. Such an inhalation exposure scenario was never considered by the company, as under “normal” conditions of use of the engine oil, only mechanics working on the engine were to be exposed, and only to cold and liquid engine oil.
The letter goes on to declare that:
Whilst NYCO can not make a statement on the potential impact of those oil vapours on the health of passengers and aircraft crew, because it is impossible to assess the exact quantity of oil being released into the cabin, the public reports of both passengers and crew members exhibiting various health disorders was a concern to NYCO and deserved attention.As the reports of doctors and university researchers indicated that most of the symptoms were consistent with organo-phosphate intoxication (neurotoxicity), similar to the symptoms of farmers exposed to pesticides, the focus was put on the organo-phosphate anti-wear additive that is present at 2-3% in jet engine oils. Tri-cresyl-phosphate (TCP), is used in all commercial engine oils with the exception of NYCO oils, as NYCO favoured the use of isopropylated triphenylphosphate (TIPP) as an alternative to TCP from the late 70’s (when TCP became listed by the French Ministry of Health as a chemical causing professional disease in that period). “Turbonycoil 600” contains this additive in lieu of TCP.
NYCO then conducted research at the University of Washington to evaluate comparatively the various organophosphates for neurotoxicity.
A total of 15 organo-phosphates were tested some being commercially available others synthesized for the purpose of the study, in order to understand the relation between chemical structure and neurotoxicity is ( which is measured by the levels of irreversible inhibition of BChE).
NYCO concluded that general rules between the chemical structure and BChE have been found and that specific organo-phosphates inducing a much lower inhibition have been identified.The best candidiates were tested to assess their efficiency as anti-wear additives in engine oil formulations. NYCO found that some could be successfully used in engine oils with an adequate adaption of the formulation, without degrading the overall oil performance.
To that end they filed a patent application concerning these new oil formulations which have the potential to reduce overall neurotoxicity “by several orders of magnitude” comparatively to oils containing the same concentration of TCP.
Switching to safer oils such as those being developed by NYCO is one possible solution, NYCO’s new formulation has already been approved for use in most airliners. Of course the best and obvious answer is to build planes like the Dreamliner where instead of bleed air, cabin air is supplied by electrically driven compressors.
There are some simple steps to be taken in the meantime according to the Aerotoxic Association:
* Installation of Bleed Air Filters * A less toxic oil formulation (like NYCO’s) * Contaminated air detectors in the bleed air supplies.
Senator Feinstein’s amendment was a good start to examining the problem, but the Aerotoxic Association believes this is not enough.
Various government and regulating authorities have commissioned research, but so far have not been able to conclusively prove a link between contaminated cabin air and chronic health problems, although numerous independent studies show clear evidence of this link. Corporate profit, conflicts of interests and ineffective control by government and regulating authorities means that the industry as a whole is in denial.
There are three ongoing court cases in the USA where both aircrew and passengers are suing Boeing for long-term ill health for aerotoxic syndrome. Recently in Australia a crew member won the first court case for exposure to a fume event linked to her health problems.
The BBC mentioned “Aerotoxic Syndrome” for the first time in September 2009 after conclusive proof from a doctor had established a link between serious ill health in pilots and breathing oil fumes, although this was downplayed by “the establishment” as not peer reviewed, according to Captain Hoyte's article.
In November, 2007 the House of Lords Science and Technology Committee asked that the chemicals in fume events be urgently identified. Cranfield University, which enjoys very close relations with BAE Systems and other highly ethical aerospace companies was scheduled to publish these findings by March 15, 2010.The publishing of the report is still pending.
WHAT ARE THE SYMPTOMS AND WHO IS AFFECTED?
Symptoms may be acute i.e. for a short period of time after a flight, or chronic i.e. long lasting, according to the Aerotoxic Association website.
Fatigue- feeling exhausted even after sleep
Blurred or tunnel vision
Shaking and tremors
Loss of balance and vertigo
Seizures
Loss of consciousness
Memory impairment
Headache
Tinnitus
Light-headed
Dizziness Confusion/cognitive problems
Feeling intoxicated
Nausea
Diarrhea
Vomiting
Coughs
Breathing difficulties (shortness of breath)
Tightness in chest
Respiratory failure, requiring oxygen
Increased heart rate and palpitations
Irritation of eyes, nose, throat and upper airways
Primarily the toxins affect the central nervous system and vary in their effects depending on the genetic and physical variables of those exposed. One persons' body may have less success than another at detoxifying contaminants and so be affected after just one exposure, while others may be exposed over long periods or after a serious fume event with little or no affect. Symptoms may be short-lived or remain long term, but with repeated exposure may become more severe and last longer.
Airlines provide no protection against fume events. The aircraft "drop down masks" partially recirculate air, so would not be effective at removing contaminants. They are designed for use only during the loss of cabin pressure. (Information obtained from the Aerotoxic Association website)
If you would like to know more visit:
www.aerotoxic.org/www.nexusmagazine.com/ http://feinstein.senate.gov
Once again attribution for all of the information from Captain John Hoyte should be credited directly to Nexus Magazine in their Feb-March 2010 Edition.
Visit their website to view the article in its entirety.
Link: http://feinstein.senate.gov
