0370 270 6000

already registered?

Please sign in with your existing account details.

need to register?

Register to access exclusive content, sign up to receive our updates and personalise your experience on brownejacobson.com.

Privacy statement - Terms and conditions

aerotoxic syndrome - claims of the future?

22 September 2015
It is often said that air travel is the safest form of travel in terms of numbers of deaths per mile travelled. However there is a growing concern by campaigners and trade unions over the health effects of flying from what has become known as ‘aerotoxic syndrome’.

At present ‘aerotoxic syndrome’ is not formally recognised by medical practitioners and crucially, a causal link between flying and any such syndrome has not been established but with the development of science and technology will that remain the case? This article considers whether this could potentially be a new wave of claims for the future and at what point could there be the potential for liability exposure.

It is alleged that passengers and flight crew are becoming poisoned by cabin air that is contaminated to toxic levels with atomized engine oils or other chemicals, however the syndrome is not formally recognised as a medical condition.

Given the altitudes passenger aircraft fly at, warm compressed air is pumped into the aircraft cabin to provide a comfortable environment and to allow sufficient air pressure for passengers to breathe. This compressed air is taken direct from the jet engines and is known as ‘bleed air’.

Bleed air comes from the compressor section of the jet engine which has lubricated seals to keep the air and engine oil separate. These seals can wear due to heavy usage or fail and this can then allow oil to enter into the compressed ‘bleed’ air which can result in fumes entering the aircraft cabin.

Jet engines differ from other internal combustion engines such as cars in that they operate at much higher temperatures and therefore they use special synthetic chemicals as oil. They also contain organophosphate additives as anti-wear agents and other aromatic hydrocarbons as antioxidants. Some of the oil gets partially decomposed i.e. chemically altered (pryolysed) due to high temperatures in the engine.

The combination of oil, additives and decomposition products - in particular the toxicity from the last two elements - entering the ‘bleed air’ is alleged to result in contamination known as a ‘fume event’.

The Unite Union which represents 20,000 flight staff have been campaigning to raise awareness of these alleged fume events and the health implications of the same. However the definition of a ‘fume event’ is not agreed upon and so there are no accurate figures as to how often these events are said to occur. The UK Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) accepted that fume events occur on 1 flight in every 100 in a 2007 report. Uncensored safety reports submitted to the Civil Aviation Authority (CAA) however apparently suggest that between April 2014 and May 2015 there were 251 incidents of fumes or smoke inside passenger jets operated by a British airline and illness was reported in 104 of those cases. The Aerotoxic Association, which is a group campaigning on the issue, estimates that “a quarter of flights suffer slight but significant contamination”, however given that contamination may be continuous throughout a flight “the total exposure might end up as much as after a brief fume event”. 

Symptoms of aerotoxic syndrome are said to include fatigue, headaches, tinnitus, dizziness, nausea, vomiting etc and therefore may be put down to jet lag or other recognised disorders. The effects of short exposures usually resolve themselves but it is the campaigners’ case that serious or repeated low dose exposures can lead to severe symptoms including permanent neurological damage. Alternatively Professor David Coggon of COT stated that “the acute illness which has occurred in relation to perceived episodes of contamination might reflect a toxic effect of one or more chemicals but it could also have occurred through ‘nocebo effects’” i.e. where people report ill health if they think they have been exposed to something harmful regardless of whether it has actually happened.

Although the toxicity of heated jet oil has been known since the 1950’s, aerotoxic syndrome has not gained official acceptance amongst aviation medicine specialists. Whilst the Aerotoxic Association state that numerous independent scientific studies have produced clear evidence of contaminated cabin air being the cause of chronic health problems, various government and regulatory authorities have commissioned research which, whilst recognising an association between contaminated cabin air and chronic health problems, have stopped short of accepting causation. An assessment by the UK’s House of Lords Science and Technology Committee found that claims of health effects were unsubstantiated. An updated report in 2008 found no significant new evidence. 

Stanhope Payne, the senior Coroner for Dorset however investigated the death of a British Airways pilot, Richard Westgate, in December 2012 and said that he was “concerned about the presence in his body of organophosphate toxins that are present in aircraft cabin air.” Such was his concern that British Airways and the Civil Aviation Authority (CAA) were sent a Coroners Rule 28 ‘prevention of future deaths report.’ In its submission to the coroner the CAA said "there is no positive evidence of a link between exposure to contaminants in cabin air and possible acute and long-term health effects" although it concedes "such a link cannot be excluded". British Airways said “The evidence does not support the conclusion that there is a risk that future deaths will occur unless action is taken.”

As recently as May 2015 the Aviation Policy Division of the Department for Transport (DfT) has stated that “Given the current understanding of the level of risk (from fume events) DfT does not plan to undertake any additional research on this issue.”

It is clear that science is constantly developing and aiding our understanding of the health risks posed by the world around us. At present there is no evidence of a causal connection between ‘fume events’ and risks to health and so any claim for alleged injury is unlikely to be successful. However, as with all new potential occupational diseases, scientific advancement could recognise such a connection in the future and there is clearly mounting pressure from campaigners for that recognition. In the meantime, manufacturers and employers should keep abreast of the evidence available and not close their eyes to potential risks. 

The following fundamental guidance laid down by Mr Justice Swanwick in Stokes v Guest Keen and Nettlefold (Bolts and Nuts Ltd) [1968] 1 WLR 1776, is worth bearing in mind as a statement of general principle:

“The overall test is still the conduct of the reasonable and prudent employer, taking positive thought for the safety of his workers in the light of what he knows or ought to know; where there is a recognised and general practice which has been followed for a substantial period in similar circumstances without mishap, he is entitled to follow it, unless in the light of common sense or newer knowledge it is clearly bad...”

What an employer ‘knew or ought to have known’ will inevitably include an objective measure against industry standards and will have regard to medical or general industry literature in terms of a date of knowledge by which a reasonable employer should be aware of the risks. So employers can be advised to watch this space and respond accordingly.

focus on...

Legal updates

Non-payment of insurance premiums during the Coronavirus pandemic

The forced closure of many businesses as a result of the Coronavirus pandemic has had a huge impact on the nation’s Gross Domestic Product (GDP). Recent reports from the Office for National Statistics state that the economy was 25% smaller in April than it was in February this year.


Legal updates

Noise-induced hearing loss claims – documentation and the expert engineer

Guest writer, Finch Consulting Senior Consultant Teli Chinelis applies his expertise in preparing engineering reports in relation to noise-induced hearing loss (NIHL) claims to explain information that is required from the claimant and information that is required and is advisable to be retained by employers, in order to ensure that claims can be fairly represented.


Legal updates

Contingent loss in negligence claims

Contingent loss is relevant to limitation; specifically, the date at which a claimant’s cause of action accrues for the purposes of a claim in the tort of negligence (as many claims against professional advisers are framed).


Legal updates

Legal and regulatory monthly update - September 2019

The latest update covering delegated authority, insurance product development, the senior insurance managers regime, data protection, operational control frameworks, Lloyds market, and horizon scanning.


The content on this page is provided for the purposes of general interest and information. It contains only brief summaries of aspects of the subject matter and does not provide comprehensive statements of the law. It does not constitute legal advice and does not provide a substitute for it.

mailing list sign up

Select which mailings you would like to receive from us.

Sign up