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Toxic Airline Air?

Posted by Jane Akre
Friday, April 30, 2010 3:33 PM EST
Category: On The Road
Tags: Toxic Air, Bleed Air, Airliine Industry, Southwest Airlines, US Air, Boeing, Neurotoxins, Environmental Health

Toxic airline air may be responsible for a host of problems from the fumes bleeding in from engine leaks.

Toxic Airlines


IMAGE SOURCE: WCNC Television, Charlotte, NC Web site

Upon the return of a US Airways Boeing 767 flight last January from St. Thomas, Virgin Islands to Charlotte, N.C. an ambulance met passengers and crew.

Even the pilot was taken away on stretcher along with eight people treated at the scene and seven crew hospitalized, treated and released.

All complained of headache and nausea coming from a suspicious smell.

The crew log notes a “very strong odor smelling like wet sox [sic] and or dirty feet circulating through the pass cabin and flt deck” reports WCNC.

The plane had just been put back in service after two hydraulic leaks the previous month.

Bleed Air

Cabin air is a 50-50 mixture of air brought in from the outside filtered through HEPA filter to pull out microbes and viruses, and something called "bleed air," named because is passes over, or bleeds off the engines.

Engine oil contains an anti-wear chemical, tricresylphosphates (TCPs), an organophosphate found in nerve agents, pesticides and insecticides. The neurotoxin is known to cause respiratory disease, bronchial spasms, dizziness, fatigue, impaired cognitive function, headaches, speech impairments and nerve impairments including tremors.

Bleed air is pressurized and cooled but not filtered. If an engine oil seal leaks, the bleed air can bring toxic fumes into the cabin, creating a smell or fine mist.

In 2002 the National Academies of Sciences' National Research Council reported "contaminant exposures result from the intake of chemical contaminants (e.g., engine lubricating oils, hydraulic fluids, deicing fluids and their degradation products) into the Environmental Control System and then into the cabin."

An isolated incident?

Judith Murawski, a scientist with the Association of Flight Attendants studies air cabin contamination and tells WCNC this is not an isolated incident. Her research shows that fleet wide there is an average of 0.86 incidents of contamination in the cabin and flight deck every day.

And more cases are coming to light:

* The Aerotoxic Association includes a blog by a German captain who allegedly lost his job and his health due to contaminated cabin air.

* The German documentary “Toxic Airlines and the Aerotoxic Syndromeincludes the story of a pilot says he lost an ability to think clearly, was confused and lost muscle strength before blacking out at the controls. He is no longer flying.

* John Hoyte had been a pilot for 30 years and thought he was suffering from Alzheimer’s disease. He tells CNN Business, “I had all kinds of issues, brain fog, word finding, memory; I thought “What is going on?’ If I fly today I am going to kill myself, I’m going to kill my passengers.” He walked off a plane never to fly again in 2004. He was asked to join 25 other pilots who had positive blood tests for TCP.

* Susan Michaelis, a former pilot from Australia, published an 80 page manual on toxic air on board a number of European airlines.

* CNN reports on former flight attendant, Terry Williams, who says airplane air made her sick. “I feel like I can’t play with my children the pain is so bad I’m often left in tears.” On a MD-82 aircraft operated by American Airlines from Memphis to Dallas, Williams says in her complaint against the airline, that a smoky mist of bleed air entered the cabin. Her eyes began to water, her throat tightened and she developed a painful headaches, her complaint says.

* Victoria Vaughan Holsted and Valerie Vaughan sued Southwest Airlines over a flight they took January 27, 2009. Flight 1705 departed Los Angeles International with stops for Nashville International then Birmingham and finally Baltimore/Washington International.

An hour into the flight they began to experience hypoxia (oxygen deprivation) along with other problems. They report they alerted the flight crew, the pilot engaged the engines at full thrust and entered a steep ascent sending heated air into the cabin along with a mist. The pilot made an emergency landing in Albuquerque New Mexico. The sisters say they experienced physical and mental ailments such as memory loss and motor skill deficiencies, among other things. The sisters, age 45, say they have been forced to take extended leave from work.

When CNN took air and surface swabs inside the cabin of a flight, an analysis from the University of British Columbia, found TCP in significant not large amounts. The lab confirmed it has found TCP in almost all 40 samples it’s analyzed from various flights.

Airline manufacturers, Boeing and Airbus, which use the same ventilation system, tell CNN that fume events can occur but "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.

TCP Science

Inside a freezer at the University of Washington are the blood samples from 200 pilots and crew members who have experienced a range of mysterious illnesses including tremors, memory loss, and severe migraines.

The samples have been collected for more than five years by Clement Furlong, a professor of medicine and genome sciences who plans on analyzing the samples to confirm whether study participants were poisoned by the effects of TCP.

He believes he knows what he will find. The neurotoxin has a history. In the 1930s, TCP, when added to ginger extract, paralyzed an estimated 20,000 to 50,000 people, a syndrome known as Jake Paralysis.

TCP is not toxic immediately; it has to be converted by the body’s enzymes in the liver.

Furlong tells IB News, “What we will see is peptide with a cresyl phosphate on it. It can come from pesticide exposure, it comes from the metabolites of the TCP. TCP isn’t toxic itself but your enzymes turn it into nasty toxins.”

Furlong says the human reaction varies among individuals due to environment, diet, drug intake, and heredity.

“You may be sitting next to someone on a plane and their levels of enzymes are 100 fold higher than yours. They may convert that compound to the highly toxic inhibitor and go into tremors and you may be unaffected. Some people are defective in genes, so environmental and genetic variations exist.”

What kind of jets?

What kind of jets have this problem? All of them potentially, says Furlong.

No civilian commercial aircraft uses a bleed air ventilation system or filter, sensor or warning system to alert the crew of contamination or the cabin or flight deck. Without admitting fault, Boeing is working on fixing the problem in the new 787 which will use air straight from the atmosphere and not bleed air. And a company in France, NYCO, is working on a safer oil additive.

Furlong says the airlines have forbidden employees from discussing the problem. So how is someone to know? They don’t.

“The airlines never tell passengers they were exposed to anything. So if you have a pilot and crew that are quarantined off of work for months or years, all the passengers go to the far corners of the earth and never know they experienced an exposure.” #

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