How The Aircraft Cabin Environment Affects You
The effects of Dry Cabin Air on Flight Crews
A first-hand perspective by Dr. Walter Campbell, AP, DAOM, PhD (c)
During flight, the moisture content of aircraft cabin air ranges between 1% and 15%. The significance of this is hard to appreciate until you consider that the average moisture content of the air in the Sahara Desert is about 20%.
This means that while we are flying the moisture is being wicked off from our lungs and skin at a rate of 2 to 4 ounces per hour. Most cockpit moisture content hovers around 1%, and pilots seem to be affected at a quicker rate than Flight Attendants.
Replacing this lost water at regular intervals during flight is important for all aircraft passengers, and crucial to the good health of Flight Crews. Equally important, I believe, is the need to supplement the body with essential fatty acids (EFAs), as these are used to keep the lungs moist and stretchy. My experience is that the EFAs we need may also be corrupted by excessive dryness in the lungs and skin.
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The effects of prolonged very slow dehydration by flight crew members can be quite varied and may sometimes even seem unrelated to their current state of health. Nevertheless, my personal experience with treating Flight Crews has shown that the implications of insufficient water and inadequate essential fatty acids are significant. The impact of not drinking enough water and not supplementing the body with EFAs for several years can be quite debilitating.
One of the most important and far-reaching health discoveries I have found in resolving the pandemic dryness in flight crews over time is Dr. Johanna Budwig's protocol, using a combination of flax seed oil and cottage cheese. This mixture renders the oil water soluble and can relieve dry symptoms much faster than taking Flax Seed Oil by itself.
The flax seed oil and cottage cheese should be mixed very thoroughly in a blender - 1 cup of water, 14 tablespoons of flax seed oil to 1 lb. of cottage cheese. Take 3 tablespoons of this mixture with breakfast every day, as described in my recommendations for Flight Crews.
China's land mass is huge. For thousands of years the Chinese physician studied what may be considered indigenous health risks associated with different climates. Ailments caused by excessive dampness were associated with people living near the rice fields. People living near deserts suffered from ailments known as dryness.
Chinese philosophy divides the human body into separate houses of water and fire, Yin being water and Yang being fire. When the body is deprived of yin fluids, patterns of disharmony develop in the body that can evolve way past what we may consider a thirst. In fact, it appears that the body robs from Peter to pay Paul, resulting in an ongoing pattern of disharmony in the affected person. These patterns of disharmony work their way deeper and deeper into the body over the years as it tries to compensate for the ever-decreasing yin fluids and the increasing disruption of vital functions that sustain good health.
In my experience, the physical problems associated with dryness tend to disappear when FlightCrews take supplemental EFAs and drink at least 1 liter of water for every 10 hours of flying.
The Building Syndrome
Imagine a very tall building like the Empire State Building, and at the bottom of the building is a man with a very large wheel. The wheel controls the amount of electricity available to the building. Every night at the stroke of midnight the man turns the wheel to the right, just a very little bit, and by doing so the amount of electricity the building has available becomes less and less as the days and years go by.
The building's electrical needs vary depending on the day and the time of day, so that Monday from 9 to 5 o'clock will demand more electricity than say, Christmas Day. As each day goes by, the building has to adjust itself to a little less electricity. The adjustments the building makes are made from moment to moment depending on the need for electricity. The building's state of electrical health is predicated on the amount of electricity available, its current demand for electricity, and the damage caused by the stress induced to its operating systems.
One summer day, all of the air conditioners happen to go on at the same time. The people in the building notice that some lights begin to get brighter and dimmer at different times of the day, some lights stay the same, and some lights go off. Some computers begin to malfunction. The water in the coffee maker isn't as hot as it used to be. Some air conditioners work, some don't work as well, some don't work at all.
All these patterns of disharmony gradually worsen due to lack of electricity and the changes made from moment to moment, day to day, year to year, until the stress to the systems and the lack of electricity kills the building.
If we transfer the concept of the Building Syndrome to the human body, and substitute moisture in the body, or what the Chinese refer to as the yin fluids of the body for electricity, we can begin to appreciate the stress to the body's systems as it tries to compensate for the lack of moisture as flight crew fly from year to year.
A parallel effect on the body is its ability to generate energy. The Chinese refer to this concept as qi, (pronounced chi). As the body tries to adjust itself, more and more energy is expended to try to compensate for the lack of moisture. At the same time, the body's ability to generate energy becomes compromised as the digestive system battles to do its job in a dry environment. The combination over time of an internal dry environment and the body's decreasing ability to generate energy form in a Flight Crew member what the Chinese refer to as that individual's Patterns of Disharmony.
Patterns of Disharmony
Let us say that you travel to London and you bring home a bad case of the flu. Not long thereafter the rest of your family come down with the same flu. Since you do not want your family to suffer from this illness, you run off to the drug store and purchase one cold remedy for yourself and your husband, and another for your son. In general one pill relieves all the symptoms.
The Chinese physician has a hard time with a one-pill philosophy. To the Chinese physician each of your family members may have a different Pattern of Disharmony to the same flu virus. For example, your son who is very young and strong may have only a light fever and a runny nose. Your son is back in school in none days or less, and feels normal after ten days.
Your husband, who has been having a lot of stress at work, has a really bad diet when he is not at home, and is thirty pounds overweight may have a higher fever with chills, and an upset stomach. Your husband is out of work for ten to twelve days, and it takes him about three weeks to feel normal.
You just flew three international trips back to back so you could get extra time off. You normally suffer from chronic constipation, joint discomfort, and migraine headache. The flu gives you high fever for three days and then you suffer from severe chills and major fatigue.
It takes you two weeks to feel better, but you're still weak and easily chilled, and find that wherever you go you have to cover up to stay warm. You feel like death warmed over when you return from your first trip back. You now find that you are calling in sick every two to three months.
The same virus attacked all three of you, but the response of your body to the virus was very different. To the Chinese Physician or almost any other Alternative Physician, "one pill cures all" is not effective medicine. Moreover, to suppress the body's natural defense systems to the flu (mild fever, runny nose, mild cough with mucus), has a negative affect on the overall health of the body over time.
I also strongly recommend Healing with Whole Foods: Oriental Traditions and Modern Nutrition, an excellent reference work by Paul Pitchford (ISBN 1-55643-220-8).
How deep is the illness?
In the previous example, your son was only mildly affected by the flu. Your husband was a little sicker than your son but not as sick as you, while you were much sicker than your husband or son. To the Chinese Physician, your son had what could be considered superficial flu, your husband had an intermediate case, and your case went much deeper than that of your husband or son.
Flight Crew Dry Symptoms
I have interviewed thousands of Flight Crews over the last eight years, and compiled the following list of Flight Crew Dry Symptoms as a result. The list starts with the most superficial and works its way down to the deeper, more severe symptoms.
If you are a Flight Crew member who has been flying for a number of years, you may have some of the symptoms listed. Just as each family member above had his or her own pattern of disharmony to the same flu, so is your own pattern of disharmony resulting from a dry environment unique to you.
KNEES AND BACK MAY START TO FEEL TIGHT ON EXERTION
MILD NIGHT SWEATS
MILD BACK OR KNEE PAIN
WAKING WITH DRY MOUTH
DRY SKIN -- DRY EYES
NAIL FUNGUS -- NASAL INFECTIONS -- YEAST INFECTIONS
MILD ACID REFLUX
LIGHTER MENSTRUAL FLOW, LESS REGULAR, AND TURNS BRIGHT RED
DIFFICULTY CONCEIVING AND IN CARRYING PREGNANCY TO TERM
SLEEP BECOMES VERY DIFFICULT
BODY FEELS WARM ALL THE TIME -- HEAT IS EXACERBATED BY MENOPAUSE
PALMS OF HANDS AND SOLES OF FEET FEEL WARMER THAN THE REST OF THE BODY
MODERATE TO SEVERE KNEE, BACK AND HIP PAIN
NIGHT SWEATS INTENSIFY
ONSET OF MILD DEPRESSION
NAIL FUNGUS, NASAL INFECTIONS AND YEAST INFECTIONS INTENSIFY -- CHRONIC SINUSITIS
DIFFICULTY STAYING WARM -- THE COLD FEELS DEEPER
HEADACHE STARTS AT THE NAPE OF NECK, TRAVELS UP THE BACK OF THE NECK THEN MOVES AROUND THE TOP OF THE EAR INTO THE EYE
AVERSION TO COLD -- CHILLED EASILY
MENSTRUAL FLOW STOPS FOR MONTHS AT A TIME, MAY BE CLOTTY AND PAINFUL
HEADACHES INTENSIFY TO MAKE THE EYE OR EYES THROB (may feel like "a bolt of lightning across the eyes")
FIBROIDS -- ENDOMETRIOSIS -- CYSTS
IRRITABLE BOWEL -- ACID REFLUX -- CHRONIC FATIGUE -- FIBROMYALGIA
CHRONIC KNEE AND BACK PAIN
The House of Water and Fire
The Chinese believe the body to be the house of water (yin) and fire (yang).
Let's say you show up at a briefing for an international trip carrying a diet cola soda (a diuretic). After briefing and before you check your emergency equipment, you go to the aft galley (where you are working), you put six diet colas on ice, and tell the galley girl that these are your sodas, and please leave them alone. You do this on every flight, because you don't like the taste of water but still want to replace the fluids in your body.
You're in the back of a Boeing 777. You set the temperature in the back cabin to 74 degrees, and tell the rest of your crewmembers that if anyone raises the temperature you will kill them! You sit in your jump seat for takeoff. You start fanning yourself as you taxi down the runway, because the cabin is too hot. Your doctor tells you the reason you feel this way is because you have early menopause.
One other possible explanation, in terms of Traditional Chinese Medicine, is that your body is the house of water and fire. Without enough water and essential fatty acids in your body, the fire is not held in check and your body begins to heat up. This concept is known as False Heat, and is part of one of the eight pillars of Chinese Medicine known as hot and cold syndromes.
Hot and Cold Syndromes
Let us say you are driving your car down the highway. The internal combustion engine is creating a lot of heat, while the cooling system keeps the engine cool enough so that it can operate at an ideal temperature. Without any noticeable difference, your radiator develops a small leak. Every day your car loses a little more coolant, and the engine starts to run a little bit warmer every day, until the cooling system is completely out of coolant and the engine starts to run very hot. If you keep driving with an overheated engine, the engine parts are heated to such a point that the moving parts themselves expand and actually grind the engine to a halt; at which point the engine goes completely cold.
A common problem with senior female Flight Attendants, who rarely drink enough water when they fly, is that they start to really heat up. They feel warm all the time [not enough yin (fluid), leaving the yang (fire) unabated without the yin (fluid) to control it]. The heating up really becomes a major problem when they go into menopause, and they suffer from hot flashes and severe night sweats.
I have spoken to a number of Flight Crew members who have all the signs and symptoms of chronic yin deficiency; the viscosity of their blood is so thick that they cannot donate blood. The blood comes out either too slow or will not come out at all.
More common are the Flight Crew who have become yin deficient by not drinking enough water. They start to heat up for years, and then start to feel cold, and slowly migrate into chronic fatigue. These Flight Crews have burned out both their water and fire, and as a result have barely enough energy to get through the day. They love to sleep, but do not wake refreshed. I have noticed that a number of Flight Crew members who are easily chilled have a difficult time getting pregnant. One of my teachers once termed this "a cold uterus".
If you drink diuretics like diet cola, coffee and tea during the whole flight, and no water, these fluids cause you to lose more water through urine excretion. Combine that with the loss of 2 to 4 ounces of water through breath and skin because of a very dry cabin. You begin to dry out internally.
There is a theory in Naturopathic Medicine that I adhere to, mainly because of this observation: when Flight Crew members who have not been taking supplemental EFAs and drinking water as a regular part of their diet resume drinking water regularly, they find that they lose it by urination almost as fast as they drink it.
The theory goes something like this: when there is not enough fluid to process the waste products of the body, the waste is stored in the spaces normally used to store water. The question now becomes: how much waste has your body stored, and how is it creating a pattern of disharmony in your body in relation to your dryness, and what must you do to clean out the waste, balance the fluids, and restore patterns of harmony to your body?
The role of the Kidneys
In Chinese Medicine we look at the kidney as housing both water and fire. Kidney yin water controls fluid not only in the blood but in the organs as well. If you have a persistent dry cough the Chinese Doctor may say there is not enough Lung Yin, and would look to the Kidney Yin to solve the problem. The Kidney Yang however controls the furnace of the body, thus if you have an aversion to cold, where you chill easily and have to cover up all the time, the Chinese Doctor would look to your Kidney Yang to solve the problem.
In natural medicine you often hear the term mucus. In Chinese medicine we use the term phlegm, or damp heat, or damp cold. In general, it is the body's defense against a toxic environment - a cover up, so to speak. Phlegm and damp heat can block energy pathways and block organ function [stagnation in Chinese Medicine] in the body, and interfere with the processing mechanisms of the body, from food digestion to the circulation of your blood. Mucus can coat the intestines to protect them against a toxic diet but at the same time slow down or prevent the absorption of critical nutrients.
It has been my experience that, sooner or later, Flight Crew members who eat tremendous amounts of junk food and do not drink enough water will suffer from serious health problems.
YIN DEFICIENCY ( Fluid Disharmony )
The signs and symptoms of Yin (fluid) Deficiency
Back and Knee Tightness on Exertion [or back or knee pain]
A Dry Red Tongue
A Thready Pulse
Burning Soles and Palms
2000 - 2005
CDC Studies of the Aircraft Cabin Air Environment
At the request of and with funding from the FAA, The Center for Disease Control) has initiated research studies on exposures and health outcomes in commercial flight crew. Exposure studies have addressed cabin air quality, cabin ventilation, endotoxin levels, cosmic radiation exposures, noise, extremely low frequency electromagnetic fields, factors related to job stress among female flight attendants, and circadian rhythm disruption in female flight attendants. Health outcome studies have focused on cancer mortality and incidence, adverse reproductive health effects, and respiratory symptoms. Several of these studies were initiated due to a 1994 Congressional mandate (Public Law 103-305, Section 304) that required the FAA to establish a program to address air quality issues in aircraft including the issue of disease transmission.
An extract from the testimony of John Howard, M.D.
Director, CDC's National Institute for Occupational Safety and Health
Before the Subcommittee on Aviation Committee on Transportation and Infrastructure, United States House of Representatives - June 5, 2003
Commercial Aircraft Cabin Air Environment
The aircraft cabin environment represents a unique occupational setting. Indoor air quality problems in aircraft cabins may differ from those in commercial office buildings because of higher occupant density and lower ventilation rates per occupant in aircraft.
The aircraft environmental control system incorporates ventilation, heating, cooling, humidity control, and pressurization functions. Outside air is brought in through the engines, conditioned by the environmental control system, mixed with filtered re-circulated cabin air, and then delivered to the cabin.
The aircraft cabin environment is characterized by reduced air pressure, lower partial pressure of oxygen, low humidity, air supply that is passed through aircraft engines, proportions of re-circulated air, and the inability of occupants to leave at will, including flight crew members whose shift lengths can exceed 14 hours.
Cabin air contaminants may include carbon monoxide; nitrogen oxides; particulates and aldehydes; contaminants from de-icing, cleaning, disinfection, and anti-corrosion agents; chemical and microbial off-gassing from materials; pesticides; and allergens. Airplane system failures may lead to cabin air contamination with engine oil or hydraulic fluids. In addition, human beings produce carbon dioxide, bacterial and viral aerosols, ethanol, toluene, acetone, and other gases and vapors. Sufficient aircraft ventilation is needed to ensure these contaminants are at acceptably low levels for flight crew and passengers.
Establishing a causal connection between cabin air quality and the health complaints of flight crew and passengers is extremely difficult since there is no systematic collection of symptom data. Elevated ozone concentrations have been associated with airway irritation, decreased lung function, exacerbation of asthma, and impairments of the immune system. During abnormal operating conditions (e.g., poor maintenance, unexpected equipment failure), exposure to engine oils and hydraulic fluids and their potential degradation products may occur, but no data have definitively linked these exposures to reported health effects.