Because the air at high altitudes is too thin to meet our breathing needs, a breathing air supply is needed for passengers and crews. On all currently flying commercial jet aircraft (except the Boeing 787), this breathing air supply is taken, unfiltered, from the compression section of the engines in a process known as ‘bleed air’.
Due to limitations of aircraft engine design, for over 60 years, the aerospace industry has known that this ‘bleed air’ becomes contaminated with toxic chemicals which are produced when the lubricating oils are heated; thus contaminating the ‘bleed air’ (the air we are supplied to breathe) in an unpredictable quantity.
However, instead of implementing solutions to protect passengers and crews from inhaling these toxic chemicals, the aviation industry continues to withhold this information from the travelling public and collectively deny that the chemicals have any impact on health.
No published inhalation toxicity data exists in the public domain, yet some oil cans state ‘Do not breathe mist or vapour from heated product’, 'suspected of causing cancer' and are listed as being a 'risk to infertility'.
Contaminated air is often odourless and colourless meaning it is almost completely undetectable to someone who does not know the signs (similar to carbon monoxide). As contamination levels increase many passengers and crews have described the contamination to smell like a dirty sock, wet dog or gymnasium. When the contamination levels are severe you may even see visible smoke.
Many crew unions have come together to form the Global Cabin Air Quality Executive (GCAQE), a not-for-profit organisation specifically set up to help resolve this issue. The largest conference (The Aircraft Cabin Air Conference) ever held on the issues raised in the film took place in London on 17th - 18th September 2019.