Extract from the Telegraph:
"According to the Department for Transport there were 116 reports on contaminated air submitted to the Civil Aviation Authority in 2007.
Hundreds of reports of fume incidents have also been filed by pilots across the world in recent years.
They deal with what happens when toxic air seeps into the cockpit or the cabin from the engine.
Critics have accused the aviation industry of trying to cover up a long-established problem, although this is strongly denied by airlines.
The impact of toxic fumes – known as “aerotoxic syndrome” by specialists – can be dramatic.
Neils Gomer, the captain of a Swedish aircraft, was rendered almost helpless. He said many of the 73 passengers on board his aircraft fell into a very deep sleep.
It was such incidents and a battery of complaints by pilots which led to the establishment of the Committee on Toxicity."