'No evidence' nut allergens can be spread through aircraft air conditioning, major review finds

There is no evidence nut allergens can be spread through aircraft air conditioning, a major review has found.

The UK’s Civil Aviation Authority (CAA) commissioned a systematic evidence review dating back to 1980 which shows nut residues on surfaces - such as tray tables, and seat-back video screens - pose the main risk. It concluded that while nut allergens can be detected at very low levels in the air when shelling, the dust settles quickly and can only be detected in very close proximity to the nuts, suggesting very little dust circulates in the air.

Some airlines have tried not serving nuts on board but fears have still been there about severe anaphylactic shock reactions during flights as they cannot guarantee it is a 100% nut free environment.

Author Professor Paul Turner, of Imperial College London, and his team are now in talks with major airlines about their findings. He said: "People shouldn't be worried about what food is being transmitted in the air when they fly.

"We didn't find any evidence that nut particles could travel through the cabin ventilation system on planes and cause reactions. On top of that, the vast majority of people with food allergies don't react to the smell of food, even if they are allergic to very small amounts.

"The one thing people must do to protect themselves is to clean their seat area. Allergenic food is really sticky, 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.”

The experts said aircraft nut ban announcements are "unlikely to be effective" and may even give people with nut allergies a false sense of security. They are now calling on fast-turnaround budget airlines to focus on properly cleaning tray tables and seat surfaces between flights.

The review, published in the journal Archives of Disease in Childhood, calls for passengers with nut allergies, or their carers, to be given extra time to ensure that their seat area is clean to avoid "accidental reactions". Airlines should instead give people with allergies "pre-boarding" so they can wipe down their seat area, they added.

Prof Turner added: "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. 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.”

The authors said that people at risk of a severe allergic reaction should carry two pre-filled epi-pen devices at all times - including when flying and airlines should consider including a separate supply of "general use" adrenaline autoinjectors.