We revealed yesterday how a Norfolk man is at the heart of a campaign to prove contaminated air inside planes poisoned him, dozens of fellow cabin crew and even passengers. Investigations editor David Powles takes a closer look at the issue.
What is this all about?
Former pilot and Norwich man John Hoyte is the founder of a group called the Aerotoxic Association. They, and a growing number of pilots, scientists and MPs, believe that potentially thousands of air crew and passengers may have been poisoned by contaminated air when flying.
It is believed the current system on most commercials planes of drawing air for the cabin through the engine is flawed, because if a fault occurs in the seals of the engine, known as a 'fume event', the air will be exposed to potentially harmful oil particles, which then pass into the cabin.
Complaints by pilots, air crew and passengers following exposure to such chemicals range from migraines, tiredness and breathing problems, to memory loss and depression.
In 2013, Prof Alan Boobis, director of Public Health England's Toxicology Unit, predicted fume events occur in 'one in every 2,000 British flights', but the levels of air contamination 'are low' when these happen.
Campaigners say there is growing evidence he was wrong.
Why have I not heard of this before?
One former Norfolk pilot compared this issue to the Al Gore film 'The Inconvenient Truth'. Campaigners claim the issue has been brushed under the carpet because influential, major airlines realise an admission would potentially cost them millions of pounds in litigation cases.
Why have the claims come to the fore now?
The subject has received growing exposure in recent months and a possible turning point was the opening of the inquest into the death of pilot Richard Westgate.
Despite the full inquest still not being heard, the coroner Sheriff Stanhope Payne took the step of writing to both British Airways and the Civil Aviation Authority (CAA) outlining his concerns that people regularly exposed to fumes circulating in planes faced 'consequential damage to their health' and calling for action to prevent further deaths.
Just last month Berkshire coroner Peter Bedford said there was a chance Matthew Bass, a long-serving British Airways steward, may have also died from aerotoxic syndrome.
Meanwhile, the union Unite is pursuing legal cases for 17 of its members who claim to have been made ill.
The campaign is also building up momentum in parliament and earlier this year Henry Smith MP called for a debate on the issue in the House of Commons. Campaigners want an independent public inquiry.
Mr Hoyte was also heavily involved in a recent feature length thriller film called 'A Dark Reflection', which was financed by many of those backing the campaign.
The campaign is growing momentum not just in the UK, but all over the world. In Australia, an influential 2000 senate report raised concerns about aerotoxic syndrome as well as a series of recommendations around future safety, of which few have been adhered to.
How concerned should the public be?
It is important to state that not everyone is believed to be susceptible to organophosphates (OP), the chemical which causes the problems.
While the figure of one fume event in every 2,000 British flights sounds small, there are 6,000 flights coming in and out of our airspace every day.
Campaigners claim recording of fume events is poor and that some may take place without people even knowing.
Mr Hoyte claims to have dozens of submissions from members of the public who have been affected.
What do the government and airlines say?
This is where it gets complicated as they have maintained a firm stance on this subject.
They refer to a 2013 Committee on Toxicity report which looked at several of the findings of past studies to draw up 13 conclusions, which included;
Contamination of cabin air from engine oil does occur and episodes of acute illness have occurred in relation to perceived episodes of such contamination.
A number of air crew do have long-term disabling illness, which might be caused by the toxic effect of chemicals, but could be something else.
But the patterns of illness reported do not conform with what would be expected from OP poisoning.
Contaminated air as a cause for the illnesses is unlikely, but uncertainties remain and it cannot confidently be ruled out.
What happens next?
The two inquests still have to be held in full and will be closely monitored by the government, aviation industry, air crew and the public.
As far as Mr Hoyte is concerned he says he will continue to fight for a public inquiry and for safety improvements to be implemented by the airlines.
His campaign group issues charcoal-face masks which passengers can use in a fume event.
The group believes no future airlines should be designed using the air systems in question, pointing to the new Boeing 787 Dreamliner, which doesn't draw air through the engine, as the future of air design.
They say older jets should be fitted with filters.
CASE STUDY 1 - 'The airlines are running scared'
Peter Lawton, 66, a retired former commercial pilot from Great Massingham, said: 'I think the airlines and the CAA are running scared. They know they have to do something but, in the words of Al Gore, this is an inconvenient truth.
'There's no doubt in my mind there is an issue here, but I think there are those who oppose it at every turn because they know how far it will go.
'It needs a public outcry and petitions to be signed so that parliament has to debate it.'
CASE STUDY 2 - 'I fully believed this happened'
Malcolm Purvis, 65, a commercial pilot for 22 years before he retired five years ago and from Sloley, in north Norfolk, said: 'When I worked for KLM at the end of my career I started to see evidence about this. They started to record the levels of toxins in cockpits and doing studies.
'I always had sinus issues, but nothing to the level others have reported. However, I fully believed this happened and people have suffered.
'Generally the attitude of pilots might have been that it was part of the job, but if I had started to feel ill I think I would have liked them to do something about it.'
CASE STUDY 3 - Julian Soddy
Capt Julian Soddy, a former pilot from Mattishall, has regularly spoken about the sickness he encountered, taking part in a 2008 BBC Panorama report on the subject and a documentary called Welcome Aboard Toxic Airlines.
He was grounded in 2000 after going to see a GP who identified his symptoms as being as a result of organophosphate poisoning.
He believes it was regular exposure, rather than a one-off incident, which caused it, saying in the book Aerotoxic Syndrome: 'I had severe flu-like symptoms every time I flew and they just became worse. As we climbed through about 10,000 feet, my head would be bunged up, I had headaches and shortness of breath.'
THE UNION'S VIEW
The Unite union has also set up a hotline for members who fear they may have been exposed and a register of fume events.
Alex Flynn, its spokesman, said: 'We know that there will be an issue of cost for the airline industry - but what cost can you put on people's health?
'We dealt with asbestos in the past and our experience then was that the industry said there was not a problem, even when there was proof. We are in the same position here.
'The cabin is the office for our members and we will do all we can to ensure they can operate with piece of mind.'
INFLUENTIAL BACKING
The campaign has backing from former Norwich North MP Dr Ian Gibson, as well as Clive Lewis, MP for Norwich South.
Dr Gibson said: 'Although it's had an impact for years, there hasn't really been any huge tragedies associated with it which is perhaps why it hasn't picked up momentum. There are also big companies behind this of course.
'There is going to have to be action. They are going to have to fit technologies to protect people from this chemical - or take it out of certain things.
'This has great parallels with asbestos and it took many years to change the world around and realise that asbestos could cause cancers.'
ANOTHER NORFOLK LINK
The chemical which it is believed is causing aerotoxic syndrome is the same one that can be found in sheep dip and in some pesticides, the focus of an investigation by this paper last week.
In fact, one of the first scientists to raise concern about the potentially harmful impact of organophosphate (OP) exposure was Professor Solly Zuckerman, who taught at the University of East Anglia between 1969 and 1974 and was also Chief Scientific Advisor to the government.
In 1951, Professor Zuckerman, who eventually took the title, Baron Zuckerman, of Burnham Thorpe, chaired a working party which produced a report for the agriculture minister called 'Toxic Chemicals in Agriculture.'
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