Passengers and crews are being exposed to an air supply from the engines which is NOT filtered which is sometimes becoming contaminated with pyrolised synthetic engine oils and hydraulic fluids. Passengers are not being advised they have been exposed and most crews are reluctant to talk out, hence why AOPIS was set up in 2001. These specialist engine oils are NOT like car engine oils and contain organophosphates (OPs). There are many types of OPs but the ones currently of interest to the aviation community are contained in Mobil Jet Oil II (which is used by over 50% of jet engine manufacturers), along with other hydrocarbons and solvents in the oil, such as PAN (CAS NO: 90-30-2) which is a known skin sensitiser at 1% and above. Mobil label the oil as containing the OP tricresyl phosphate (TCP) 1-5% Wt, however, during the recent Australian Senate Inquiry looking into the 146 problem, they confirmed that the TCP actually contains two Di-ortho (DOCP) isomers & three monoortho (MOCP) isomers. These have been identified by scientists as being more toxic than TOCP, the only ortho isomer previously acknowledged in the oil. It is suggested that a statement of low TOCP content underestimates the toxicity of the -OCP ingredients by a factor of over 30,000 times. Airlines say their is no risk from inhaling contaminated air despite the fact evidence throughout this website clearly shows this is not the case. Mobil who are one of the main manufacturers of these synthetic jet engine oils advised the Australian Senate Inquiry on 1 Feruary, 2002: "Mobil do not consider accidental exposure to oil vapours in an aircraft cabin to be 'normal use', but the levels that can be reached are comprehended by our internal and published risk assessments and are considered safe". Interesting conclusion when they have never tested the chronic neurotoxic effects of inhaling their pyrolised oils. Passengers and crews globally ARE becoming sick with 'Aerotoxic Syndrome' medical effects but the airline industry fails to take action to protect crews and the travelling public.