Very low levels of toxic TCP found in 737 cockpits, says KLM

Dutch scientific research institute TNO has only found very low levels of dangerous fumes in aircraft cockpits during flights, airline KLM said on Friday.

The institute was asked to investigate concentrations of TCP – a neuro toxin – in relation to a court case brought by a KLM pilot. He says he became ill by breathing in TCP which is found in cockpit air.

But TNO’s research found average TCP levels well below the permitted level and no traces of the most toxic type of the compound ToCP, KLM said on Friday.

20 flights

TNO conducted its research on 20 flights operated by nine different KLM Boeing 737s. The levels found were also much lower than those found in previous international studies, KLM said in a statement.

The airline described the results as ‘reassuring’.

Television current affairs show Zembla said earlier this year that up to 35 cases of possible cockpit air poisoning were being investigated in the Netherlands.


 A spokesman for the pilots’ association VNV told the NRC the concentrations of TCP may be very low but ‘pilots do have certain symptoms and we want to know if there is a link between those symptoms and the presence of TCP.

The research showed TCP is present in cockpits, the spokesman told the newspaper. ‘We want to know if these low concentrations can cause health problems.’

The NRC said the Dutch public health institute RIVM is starting wider research into TCP in January.

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