A new study has found that there is no evidence suggesting that people with nut allergies are at risk from nut particles in aircraft ventilation systems.
The research, funded by the UK Civil Aviation Authority and the UK Medical Research Council and carried out by a team from Imperial College London and the Aviation Medical Consultancy, found that allergic reactions to foods happen between 10 and 100 times less frequently on planes than they do “on the ground”.
While they recognised that this could be thanks to the extra precautions passengers with food allergies might take when travelling, the scientists said the fear of airborne particles that causes airlines to make announcements banning the consumption of nuts on board, appears unfounded.
Airplane air cleaner than hospitals and classrooms
Pointing out that air circulates across the cabin, not through it, and that filtering systems remove most dust, vapours and food particles, the review notes that the air inside an aircraft is completely exchanged every three to four minutes during a flight, more often than in hospitals and classrooms.
“We didn’t find any evidence that nut particles could travel through the cabin ventilation system on aeroplanes and cause reactions,” said Professor Paul Turner, a specialist in anaphylaxis and allergy at the University of Sydney and Imperial College. “Announcements requesting nut bans are not therefore supported, and may install a false sense of security,” he concluded.
Food residue is the real risk
According to the study’s findings, a greater risk comes from the residue of food that might be left in people’s seats from previous flyers’ snacks and meals. “Allergenic food is really sticky,” Turner said, “and can be found on seat surfaces, table tops, and seat-back entertainment screens. People touch these surfaces, and then the allergens can be transferred to their mouths.”
Unless airlines ban nuts and other allergens on all flights, the best way to avoid the risk residues pose is to allow people with allergies extra boarding time to ensure that their seats and surroundings are free of potentially fatal crumbs and dust.
“The one thing people must do to protect themselves is to clean their seat area,” Turner said, adding, ““If food-allergic people can board first, and have time to clean their seat area with something like a baby wipe or antibacterial wipe, they are much less likely to have accidental reactions.”
Simon Williams, chief executive of Anaphylaxis UK, echoed the researchers’ recommendation about cleanliness: “A key take-home message is the importance of passengers cleaning their seat area, including the tray table and the seat-back entertainment system,” he said.
No more nut announcements?
It may be therefore that airline announcements banning nuts become a thing of the past, as the research team has been in touch with airlines to explore better frameworks and share best practices when it comes to managing customers with dietary restrictions.
“We’re having discussions with a number of major airlines as well as patient groups and anaphylaxis charities to see if we can get some consistent changes in airline policy across airlines operating out of the UK and internationally, to reflect what the evidence is and really make a difference to food-allergic passengers,” Turner said.
