FLYING a plane should come with a health warning, according to research led by the University of Stirling.

The new study is the first of its kind to look in-depth at the health of aircrew who are suspected to have been exposed to contaminated air during their careers.

It reveals a link between exposure to air supplies contaminated by engine oil and other aircraft fluids, and a variety of health problems.

The scientists confirmed a group of more than 200 aircrew had been exposed to a number of substances through aircrafts' contaminated air and reveal a clear pattern of acute and chronic symptoms, ranging from headaches and dizziness to breathing and vision problems.

Dr Susan Michaelis, of the University of Stirling’s Occupational and Environmental Health Research group, said: “This research provides very significant findings relevant to all aircraft workers and passengers globally.

“There is a clear cause-and-effect relationship linking health effects to a design feature that allows the aircraft air supply to become contaminated by engine oils and other fluids in normal flight. This is a clear occupational and public health issue with direct flight-safety consequences."

The experts conducted two independent surveys to review the circumstances and symptoms of aircrew working in the pressurised air environment of aircraft. The symptoms were confirmed using medical diagnoses.

One test looked at pilots’ health and showed 88 per cent were aware of exposure to aircraft contaminated air. Almost 65 per cent reported specific health effects, while 13 per cent had died or experienced chronic ill health.

The other test looked at specific oil leak incidents. 80 per cent involved fumes only and all of the events took place when the aircraft was preparing for, or in, flight.

Two-thirds of the incidents involved further reports of fumes both before and after the incident. Also, 93 per cent of the incidents included symptoms ranging from in-flight impairment to incapacitation and almost 75 per cent consisted of adverse effects in more than one crew member, with anywhere between 10 and 23 different symptoms reported in relation to 47 per cent of events.

Approximately 87 per cent of the incidents confirmed oil leakage from the engines during subsequent maintenance investigations.