Fume events in aircraft cabins cause no danger to crew or passengers, the UK's Cranfield University has concluded, after it carried out a study involving 100 flights.
Cranfield was contracted in 2008 by the UK Civil Aviation Authority and the UK Committee on Toxicity to conduct the study, and it co-operated with several airlines to test on flights by five aircraft types.
These included the British Aerospace BAe 146 and Boeing 757 as well as the Airbus A319, A320 and A321. A series of air samples were taken at specific points on all the flights, and additional samples if a fume event occurred, to analyse its content for volatile or semi-volatile organic compounds, carbon monoxide and particles.
During 38 of the flights at least one pilot, cabin crew member or researcher reported fumes or smells. But the report also stated: "No fume event occurred during this study which triggered the airline's formal reporting procedures."
It said that neurotoxins were present, but the levels measured were acceptable according to standards applied to the workplace or the home.
UK minster for transport Theresa Villiers said: "The Department [for Transport] will always take the health of persons on board aircraft very seriously and I hope the publication of this thorough and independent analysis by Cranfield University will provide reassurance on this issue."
She said that the Department will "now take forward" another outstanding cabin air study, swab test research being conducted by the Institute of Occupational Medicine in Edinburgh.
But Tristan Loraine, a member of the Global Cabin Air Quality Executive and a former British Airways pilot who lost his pilot licence as a result of health damage by cabin air contamination, said he disagreed with the report's conclusions.
He said that several isomers of the highly neurotoxic chemical tricresyl phosphate were detected in the cabins during the Cranfield tests, and that the presence of these is unacceptable even at the detected levels.
Loraine said there are no stated levels of toxic chemicals published for the travelling public's protection, so for the report to state, as it does, that the levels found were acceptable is meaningless. The trial was invalid, he added, because it was not able to measure the chemicals present during a reportable event.
UK pilots union BALPA said the Cranfield study is a "major contribution", along with the swab research, to the scientific study required on the toxicity issue. Secretary general Jim McAuslan says: "Irrespective of the Committee on Toxicity's conclusions there are examples of pilots who get ill and BALPA will continue to explore this as a matter of concern."