Health

While the focus of air safety is largely on crash prevention, passengers and crew may face a potentially greater risk from aerotoxic syndrome, a condition experts have dubbed ‘the asbestos of the skies’. By Linda Moon.

Aerotoxic syndrome

Former pilot turned aviation health and safety consultant Dr Susan Michaelis.
Credit: SUPPLIED

Nearly three years ago flight attendant Jessica Manning was exposed to 21 hours of engine fumes aboard a flight. In the years that followed, the previously healthy Queenslander suffered persistent skin lesions, 75 per cent hair loss, vision deterioration, multiple chemical sensitivity, impaired short-term memory and cognitive function, liver and brain tumours, crippling fatigue and more. “I was told to not risk having babies as they could have Agent Orange-like issues,” she says. “I felt like I had chronic fatigue and Alzheimer’s.” Manning lost confidence, friends and suffered relationship problems due to her symptoms.

Manning, whose real name has been withheld for legal reasons, believes her ongoing health problems stem from exposure to known neurotoxins while flying. And with the number of crew and passengers traversing the skies growing each year, so does the risk of contracting similar maladies.

In 1999, Chris Winder, a professor in toxicology and occupational health and safety at the University of New South Wales, Jean-Christophe Balouet and Dr Harry Hoffman were the first to link toxins in cabin air to acute and long-term health injury. They dubbed it aerotoxic syndrome.

The root of the problem lies in a long-known design flaw. In all commercial aircraft (except the Boeing 787 Dreamliner), outside air is drawn through the engine to supply the cabin and cockpit. In the industry it’s known as “bleed air”. Winder’s 2002 jet oil paper describes a chilling cocktail of toxic chemicals that might find their way from engine oils into bleed air. The most significant are carbon monoxide and organophosphates, which were originally developed to kill as chemical warfare agents and pesticides.

The 2016 court documents of Escobedo v Boeing reveal Boeing – the world’s biggest manufacturer of commercial jetliners – have known of the health risks since 1953 but failed to act on warnings from aviation experts, the Federal Aviation Administration regulating body and their own air quality department.

The fight for recognition of aerotoxic syndrome has been driven largely by aircrew, and spawned more than 40 scientific papers, aviation investigations, parliamentary inquiries, documentaries, and a growing number of lawsuits. Several recent aircrew deaths: Matt Bass, 34, Richard Westgate, 43, Karen Lysakowska, 43, and James Anderberg, 53, have been linked to aerotoxic syndrome. Based on the accounts of pilots incapacitated by fumes, it has also been suggested that some aviation accidents might be due to it.

Publicly, the airline industry denies the problem. What it does acknowledge is that engine fumes sometimes leak into the cabin.

According to Dr Susan Michaelis, an aviation health and safety consultant and the world authority on aerotoxic syndrome, such fume events – often associated with a “dirty socks” odour – are under-reported and can expose those on board to hazardous levels of toxins. Additionally, a 2018 paper based on her master of science research, for which she received an award, reported extreme temperatures in the engine produce aerosolised nanoparticles that routinely pass through gaps in engine seals. “Engine seals are designed to leak in normal operation,” she says. “Whereas the aviation industry has done all they can to continue the myth that oil leakage into the air supply is a rare failure condition only.”

A former QantasLink pilot, Michaelis began experiencing aerotoxic syndrome symptoms while flying BAe 146s between 1994 and ’97, and was medically discharged from her position in 1999. Doctors have diagnosed her with chemical sensitivity, vocal cord polyps, chronic fatigue, respiratory, neurological and other abnormalities, and, in 2013, with breast cancer. “My doctors and I think there’s a strong likelihood my chemical exposures were the cause,” she says. In 2007 she was offered a payout of $250,000 in return for silence. Instead, she continues to devote herself to advancing research on the topic.

In 2010, Australian flight attendant Joanne Turner was the first person in the world to win a civil case against an airline – East-West Airlines – for health impacts related to bleed air. Ground crew and passengers have also begun to fill the files of lawyers representing aerotoxic syndrome victims. Twenty passengers won compensation in 2010 for illnesses incurred from toxic fumes on a Boeing 767 flight from London to Florida in 2007. Captain Tristan Loraine interviewed some of the affected families in his 2007 documentary Welcome Aboard Toxic Airlines. “By coincidence the return plane was delayed by three or four hours,” he says. “The kids played with each other and the mums started talking and they soon realised that pretty much everyone who was on the plane that flew out had spent the last week sick.” Without those conversations they wouldn’t have made the link to the flight.

Dr Jonathan Burdon, a consultant respiratory physician in Melbourne, and co-author of scientific papers on aerotoxic syndrome, says the classic symptoms of organophosphate poisoning can mimic jet lag. They include foggy thinking, dizziness, memory problems, fatigue, headache, tremor, sinusitis, nausea and balance and breathing difficulties. Organophosphates, typically absorbed by inhalation or through the skin, have their greatest impact on the neurological and respiratory system, but can also produce gastrointestinal symptoms, he says. “There’s a huge variation of symptomology. Not everyone gets everything.” Many of his patients continue to suffer from serious health problems years after exposures.

At present there is no recognised diagnostic test for aerotoxic syndrome. “It’s a clinical diagnosis based on symptoms,” Burdon says. However, it is possible to measure organophosphate exposure in a person’s bloodstream or urine. “There’s now a strong background of solid, respected practitioners who think this is real. It’s a huge occupational health and safety issue no different to the asbestos or lead problem.”

Tristan Loraine, the spokesman for the Global Cabin Air Quality Executive, says passengers are never told or followed up when they’re exposed. “Eleven million people fly every day. What about the pregnant mother? Let’s say her child is born with some kind of problem – she’s never in a million years going to make the link to the aeroplane.

“Pick up a tin of oil or a tin of hydraulic fluid. It actually says on the tin: ‘suspected of causing cancer’, ‘risk of infertility’ and ‘do not breath heated product’. This is the stuff passengers are breathing in on their flights. How is it possible that airlines have no legal or moral obligation to tell their passengers you’re going to be exposed to some degree to this chemical when you fly?”

Even with evidence, it’s hard getting the issue addressed. “You’re dealing with the two most powerful industries in the world – aerospace and oil,” he says.

Solutions already exist. The Boeing 787 Dreamliner, which debuted in 2009, pumps air into the cabin from an inlet separate from the engine. Currently, 640 Dreamliners fly around the world (Qantas currently have four in operation). However, Boeing continue to dodge air-quality issues on their other models.

In a move viewed as the industry’s first acknowledgement of aerotoxic syndrome, Britain’s EasyJet, and the United States’ Spirit Airlines will be the first to install filters developed by Pall Corporation. Todd Barrett, the president of Pall’s aerospace division, explained that a carbon stage filters out “particles, mists and organic vapours”. The company is also developing a sensor that monitors cabin air contamination.

Qantas, Jetstar, Virgin Australia and Tigerair Australia say they have no plans to install the filters or sensors. However, Loraine recommends that filtration systems be installed on all aircraft to reduce aerotoxicity, “Would you pay another dollar to have clean air? You have to pay to choose your seat, but the most important thing to human survival, the air you breathe, nobody thinks about it.”

Currently, there is no legal imperative upon the airlines to install air filters, according to Michaelis. “There’s a gap between aircraft regulations and standards, and means of compliance for provision of clean air in crew and passenger compartments. Many people are at specific risk – the young, elderly, infirm and the unborn foetus [as well as] crew and frequent flyers due to repeated low-level exposure.”

She’d like to reignite the issue in Australia. “It’s been a long battle,” she says.

This article was first published in the print edition of The Saturday Paper on May 4, 2018 as "The air up there". Subscribe here.

Linda Moon
is a freelance health and lifestyle writer.