American Morning

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March 12th, 2010
07:00 AM ET

Testing for toxic air

By Allan Chernoff, CNN

(CNN) – Could the air on board your next flight be toxic?

Cabin ventilation air comes through the engine. So, if there's an oil leak, engine oil mist – containing neurotoxins – can seep into the aircraft. Though relatively rare, it has happened on commercial flights, triggering neurological symptoms like severe headaches, tremors, and dizziness in crew members and passengers.

CNN recently tested the air on board a transcontinental flight. (We're not going to mention the airline because this is an issue affecting all airlines.)

Toxicologist Chris van Netten of the University of British Columbia, who has studied air quality on board planes for years, provided CNN with two portable air monitors. They use small fans to blow air through a filter which can capture contaminants.

On board, I don't sense anything unusual about the air in the cabin, aside from the typical airplane dryness. Once the plane is at cruising altitude I turn on the monitors, which run for about 90-minutes on battery power.

If there are toxins in the air, they should leave residue on surfaces of the cabin. So, wearing a plastic glove, I wipe the cabin wall and tray table back with sterile alcohol swabs which I then store in plastic zip-lock bags.

Shortly after our flight, I’m in a laboratory at The University of British Columbia, presenting the samples to Professor Van Netten, who places our air filters and alcohol swabs into test tubes. His research associate, Tim Ma, adds solvent to extract whatever chemicals the filters and swabs captured. The scientists also analyze strands of producer Laura Dolan's hair to see if it collected toxins from her seat back cushion.

Ma runs the resulting chemical mix through a mass spectrometer, a device that measures molecular weight and chemical composition. It's able to compare our samples to the compound Tricresyl Phosphate, a neurotoxin known as "TCP," which is in engine oil.

The finding: our swabs of the air cabin surface do contain TCP!

"It's the pattern that really nails it down to actual engine oil. This is the pattern you find in engine oil and this is the sample in the swab sample you took from the aircraft," says van Netten, pointing to a computer monitor displaying virtually identical valleys and peaks, measurements of the weight and structure of Tricresyl Phosphate. "It's like a signature. You can't be mistaken about it."

Tim Ma has analyzed surface swabs from 40 different flights. He almost always finds TCP. "The wipes are at significant levels," says Ma.

Significant, but not large. The biggest amount we find is only 44-billionth of a gram.

So, if I were to drop some food on the tray table, then eat off of it, would I be putting myself in danger? Van Netten says no, there would be no health consequences.

"The amount is likely to be relatively low, so there's no point getting all excited about that," he says.

Our air samples do not show any trace of TCP. That means toxic residue has collected on the surface of the cabin from either a prior fume event or from gradual, continual accumulation of toxins.

"There is a fair amount of remnant material floating around literally in the ventilation system which comes out on a regular basis and that's what you're measuring," says the professor. "The Tricresyl Phosphate will stick around for a heck of a long time. They don't deteriorate it seems."

Van Netten explains his research shows when engines are shut down some oil can leak overnight. In the morning when pilots turn on the engine, a mist of oil can spread through the cabin.

Laura's hair shows traces of TCP as well, apparently picked up from the airplane seat. But, the amount is only one-trillionth of a gram.

The two leading aircraft manufacturers – Boeing and Airbus, which both use the same ventilation system – acknowledge "fume events" can occur. But they say their planes deliver good quality air.

"The cabin air system in today's jetliners is designed to provide a safe, comfortable cabin environment," said Boeing.

"Airbus aircraft are designed to guarantee a proper cabin air quality under normal operations," said Martin Fendt, spokesman for the aircraft-building division of the European Aeronautic Defence and Space Company.


Filed under: Airline safety
soundoff (19 Responses)
  1. yvonne cann

    I am quite concerned by all this, as i suffer with chemical sensitivity, only been diagnosed since i last flew 7yrs ago, this causes me great problems from day to day as i have problems with body sprays, deodorants, hair dyes etc, also cleaning products, diy products, new carpets, new mattresses because of the fire retardent spray, washing products, petrol and diesel and have learned that most flights are sprayead for different reasons and now the problem with fumes etc on the plane, maybe for the sake of everyones health everyone should be made to wear a mask, yvonne x

    March 15, 2010 at 4:19 pm |
  2. stan turecki

    Allison – increased exposure to radiation in flight crews has been studied long ago. the average increase in exposure is about 0.2 rem for flight crews. This is far bellow the suggested maximum exposure limit for the public (2 rem) and even further bellow the maximum occupational exposure limits (5 rem). Now as a general rule radiation exposure is something that should be limited to the lowest practical amount, but to put this into perspective, the additional radiation exposure from working as flight crew is on par with the increased exposure that comes from living at higher altitudes, such as denver or salt lake city. even if you were to get on a plane in new york, fly to london, then fly back the same day – then do the exact same thing each and every day for a full year – you would only be at about half of what is considered a safe dose for occupational exposure.

    March 15, 2010 at 4:12 pm |
  3. stan turecki

    sadly this study is without merit – there is no control. how do you know that the TCP from your producer's hair came from the seatback cushion and not the result from contamination by running one's fingers through their hair? (TCP is commonly found in nail polish). Your air monitors show that there is no detectable TCP in the cabin air. The TCP you found on the tray table could have come from someone pumping gasoline then touching the tray table as TCP is a common additive in gas.

    Science just doesnt work as simple as someone might like. you just dont say 'ahha!' there is TCP in these samples so obviously we have a problem. with modern diagnostic equipment the reality is that if you look hard enough for something you will likely find it. most people dont comprehend the sort of minute quantity of material that can be detected by these machines. imagine an olympic sized swimming pool for a moment. now imagine 1 single drop of water. if you put that single drop of water in the pool your drop now consists of many tens of parts per trillion in the pool. thats a pretty sizeable concentration to modern analysis techniques.

    March 15, 2010 at 2:54 am |
  4. Katherine Rain

    This report was another example of irresponsible journalists pretending to understand the science of risk assessment. Risk assessment involves: hazard identification, exposure assessment, dose-response, & risk characterization.
    Yes, I'm sure there are 'toxic residues' present on aircraft surfaces (Hazard Identification). However, the report failed to inform the public that they are exposed to the same petrochemicals while sitting in their cars at a much higher concentration- and more frequently (Exposure Assessment). Inhaling hydrocarbon fumes at low concentrations for short periods which occur infrequently on a plane is a much lower-risk for over-exposure than sitting in traffic on a daily basis.
    And as for 'accidental ingestion of residues' ... Your child's playground equipment has more hydrocarbon residues than anything inside a plane. I expect better from CNN. When did you stop checking the FACTS?
    Katherine Rain, MPH
    Senior Environmental Health Scientist

    March 14, 2010 at 3:28 am |
  5. vinu

    Unfortunately, more than a hundred years after the Wright brothers flight, we have little competition in the aircraft industry. Boeing and Airbus are heavily subsidized by governments. Without competition, cabin air quality is just one casualty.

    March 13, 2010 at 8:30 pm |
  6. Allison Fernandes

    Dear Allan:

    Thank you for your story that ran on A.M. entitled, "Testing for toxic air". I just happened to catch it before working a trans-con flight yesterday. I can only imagine how much toxic build-up I may have been exposed to over the past decade and a half as an airline crew member. Analogous to cosmic radiation exposure, this particular issue regarding toxins in cabin air has not been readily or publicly addressed by the airline industry collectively. Miles of red tape exist and ensnare efforts to rectify the issue(s) due to the ambiguous relationship that exists between the airlines, the FAA, and the conflict of interest the FAA has with the dual responsibility of promoting aviation while simultaneously ensuring the safety of airline crew. Perhaps you could further investigate the risk of cosmic radiation exposure incurred by flight crew members as well. (Crew and frequent fliers typically are at risk). Thanks.

    March 13, 2010 at 2:53 pm |
  7. Robert McConnell

    The airlines should be much more concerned about the oxygen content in their planes, especially at 30,00 feet. Many of us with heart, lung and circulatory problems shorten our life further by flying on planes that are not properly oxygenated. This is often the case around seats located in the back of the plane. This dirty little secret is not discussed much be cause it costs extra money to properly oxygenate cabin air to keep everyone's blood oxygen saturation level at 90+%, much less at the 96+% recommended level. Under such minimal conditions, those of us with such health problems can easily drop to saturation levels as low as 70 or 80% at 10 to 30,000 feet which promotes severe drowsiness and confirmed cell damage.

    Lets do some research on the above very real danger that can easily be measured rather than on something that is present at levels thousands of times less than the upper regulatory limits established by the EPA, OSHA, FDA, OECD or MITI.

    March 13, 2010 at 1:39 pm |
  8. Dennis

    You take Smoking off the Planes,But Serve Booze,When smoking was taken off ALl the AIR is now Recirculated in the Planes,Your Breating everyone's rotten Breath and Diseases.Im glad.......I hope you all go under

    March 13, 2010 at 3:40 am |
  9. Sam Cole

    I was disappointed, but not surprised when I saw this report this morning. News is news! This is not news-worthy. The way this story was led up to one would have assumed that there was some frightening new development regarding air quality on aircraft. Instead CNN wasted air time to tell the world that in fact there trace elements of TCPs in the air passengers and crew breath. So little in fact that it is barely measurable and not a risk to health. In fact there are tens of thousands of times more toxins in your car as you drive on any freeway or city street.
    If you want to report on stuff like this then be honest and not try to make something out of nothing. Don't lead off with, "I if you travel on airplanes you should be aware of........"

    March 12, 2010 at 9:26 pm |
  10. dr. ben landa

    I'm an inorganic chemist by profession.What concerns me,besides the presence ofTCP is other contaminants which were not mentioned. Were other toxic compounds present? or even detected? or were the amounts below the limits of the gc/mass spectrometer detection limit?
    thanks, ben

    March 12, 2010 at 7:15 pm |
  11. Alan

    And don't forget your car. There are openings in the firewall between the cabin and the engine compartment for things like steering shaft, throttle, brake, clutch, heating/ventilation controls, wiring and so on.

    Fumes from under the hood can leak into the car, you can easily smell them. For example, In a car burning oil you smell oil in the car. There can be other fumes too, antifreeze, transmission fluid, fuel. If the exhaust system is leaking you could be poisoned with engine exhaust including carbon monoxide.

    I've driven lots of old cars over the years and plenty leaked fumes. Grommets vibrate loose, rubber boots deteriorate or fall off and gaps open up. If you smell anything it's a sign of trouble.

    Check or have a mechanic check that all seals and rubber boots are in good condition. All holes for wiring etc are sealed somehow. For small gaps a good DIY solution might be silicone seal. Make sure there are no exhaust leaks too.

    Your engine has an air filter on it but your lungs don't.

    March 12, 2010 at 3:45 pm |
  12. Thomas Leigh-Kendall (WALLIN)

    Aircraft are overlooked when it comes to cancer . Take a look at aircraft
    spraying crops, or fire retardent.
    When these planes are on the runway or in the air they spreed cancer causing burn off fuel. This poison gets in the air, in the ground, and in our water.
    We breath it
    We eat it and
    Drink it.
    The cure or a way to preventing cancer is, ending all use of fossil fuel..

    March 12, 2010 at 12:18 pm |
  13. James Hughey

    You might want to look into the military side of this story. Long hours in the air for military aircrew members. "Jim"

    March 12, 2010 at 11:20 am |
  14. James Hughey

    I would suggest that CNN contact Dr Clement E. Furlong, a research professor at the University of Washington. Dr Furlong believes that a "Toxic Air Syndrome" exists and is in the process of developing a simple blood test to prove it. Good story. Keep up the good work! I watch you every morning. "Jim"

    March 12, 2010 at 11:17 am |
  15. Gladys Onstott

    Here is a thought for you. How about the government giving each adult American a $1,000,000.00? The government would keep $250,000.00 and it would go into the "general fund". Don't you think most working families would pay off their homes (giving banks and mortgage companies more financial stability to produce loans). Also, people would spend money on vehicles, and other commodities. After all, it isn't Washington, and Big Business who will make this country work. It is the average American Family who will bring us back. Just think how much we would save. So easy, yet our "great" legislature "CAN'T" think of it. That $250,000 could be used to pay down out debt to China. What a concept huh?

    March 12, 2010 at 8:10 am |
  16. Gladys Onstott

    Health Care Issue: It has been an issue for over a year. Everyone crying "foul". The solution is so easy. If everyone would just have their medicare taxes increased, say $25.00/wk. Everyone in this country would have health care. We wouldn't have to do anything else. My husband and I live week to week, and we would be willing to even add $100.00 a week to that fund. Currently we have health insurance through his employer, which stinks! We have $138.00 each week taken out. If we all put into this medicare fund. Look what we could accomplish. So simple I don't see why our "learned" congressmen/women haven't thought of it.

    March 12, 2010 at 8:04 am |
  17. TURLEY Hayes

    Until scientists give the FAA proof that these toxinsare cummulative and exist on all jet flights, then there is nothing to work with. It is the same as what is happening in the Auto Industry. Give the facts, acto upon them and come down hard on the companies and manufacturers.

    March 12, 2010 at 7:57 am |
  18. brenda

    just flipped on the tv and saw this report...and how glad I am...
    I have an allergy to petroleum and to petroleum fumes in addition to tobacco and tobacco fumes, pollens and many other things.. I take allergy shots regularly and do many other things to avoid an 'immune response event' since all colds become sinus infections and my immune system is so compromised that I am antibiotic resistant..in fact, antibiotics kill off the friendly digestive bacteria in my system so not getting ill is really important to my quality of life
    for the past 20 years, every time I have flown...which is not often, thank goodness.....I wind up with a sinus attack..and now your article explains why... I thought it was the germs in the cabin from other passengers who were ill...and it probably is, but now add in the petroleum fumes...
    so...as good as your article is...I submit that passengers who have allergies are at risk as well as airline personnel. And that cabins on all planes should be tested prior to boarding..
    Guess that before I fly the next time, I will wear a mask like the one I wore on the last flight when I was concerned with getting the swine flu..
    Can I purchase a meter of my own to measure the air? I am also checking with my allergist to see if they test for TCP's, perhaps there is an antigen.
    Thank you
    Brenda

    March 12, 2010 at 7:49 am |