In Flight Organophosphates

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Concerns have been raised by organisations representing pilots and cabin crew about the possible effects on aircrew health of oil/hydraulic fluid smoke/fume contamination incidents in pressurised aircraft. Specific concerns have been raised with respect to organophosphate compounds (OPs) in the cabin air environment and the perceived effects on health of long-term low- level exposure states Professor Michael Bagshaw, MB BCh MRCS FFOM DAvMed DFFP FRAeS, in his 2013 “Health Effects of Contaminants in Aircraft Cabin Air” summary report vs. 2.5. ( Always remember: What affects cabin crew affects you, the passenger!

The UK CAA Mandatory Occurrence Reporting (MOR) System in 2007 noted 116 fume event reports out of 1.3 million passenger and cargo flights, with fume events estimated to occur on 0.05% of flights overall (1 in 2000). Of the 20,000 UK professional pilot population, the UK CAA Medical Department in 2008 was aware of 21 pilots reporting medical symptoms associated with exposure to cabin air fumes, of whom 10 are long term unfit. There has been no reported increase in the number of such pilots known to the UK CAA Medical Department.

The Australian Parliament conducted a Senate Investigation in 1999 into air safety and cabin air quality. This followed concerns raised by crew members working for Ansett Airlines who reported feeling unwell due to unpleasant odours of engine oil inside BAe 146 aircraft. The Senate report concluded that the BAe 146 had a record of unpleasant odours in the cabin as well as occasional incidents of fumes from lubricating oil. Over a longer period, airline employees had reported a variety of adverse health effects.

In the USA similar problems were reported with early RB211-535C powered Boeing 757 aircraft in which overfilling with engine oil could lead to contamination of the environmental conditioning system (ECS). In the UK, incidents of smells in the cabin were reported on early B757s operated by British Airways. UK operators of the BAe 146 also experienced oil fume incidents.

Although the evidence suggests that oil fume events of initial concern stem from a design fault on two early series aircraft, which has now been rectified, occasional oil smells still occur (~1 in 2000 flights). Campaigners maintain that these are leading to health problems for aircraft occupants. They are also concerned that crew health is being affected by long term exposure to very small amounts of contaminants, which may be present in bleed air as a result of leaking engine oil seals in the absence of specific fume events.

In 2007 the Aerotoxic Association was founded by BAe 146 Training Captain John Hoyte at the British Houses of Parliament to raise public awareness about the ill health allegedly caused after exposure to airliner cabin air that he claimed had been contaminated to toxic levels by engine oil leaking into the bleed air system, which pressurizes all jet aircraft with the exception of the Boeing 787 ( Since then, the Association has provided guidance and advice to thousands of airline pilots, cabin crew and passengers suffering from Aerotoxic Syndrome.

The term describes acquired chronic ill health caused by exposure to toxic oil fumes present in the breathing air of most commercial jets. Unaware, thousands of people suffer every day without knowing about this health and safety hazard first identified by 3 scientists from France, Australia and the USA in 1999. It is known to affect the central nervous system and brain causing a range of acute symptoms and long-term ill health. And remember, now: What affects cabin crew affects passengers!