A team of scientists from the U.K. has released a new study debunking a widespread belief about how nut allergies work on airplanes.
The common perception is that air travelers with nut allergies are at significant risk of having a bad reaction from breathing in tiny nut particles transmitted through aircraft ventilation systems as a result of fellow passengers' snacking choices.
But the researchers, who specialize in allergies and aviation medicine, found "no evidence to support airborne transmission of nut allergens as a likely phenomenon" on airplanes.
The study, titled "Flying with nut and other food allergies: unravelling fact from fiction," concluded that the air filtration systems on modern commercial aircraft are remarkably effective with regard to removing dust, vapors, and food particles from recirculated air.
That finding should sound familiar if you pored over airlines' ventilation-related safety specs during the Covid era (or was that just us?).
In fact, "food-induced allergic reactions are around 10–100 times less common during flights than on the ground," according to the scientists, who speculate that could have much to do with the "multiple precautions food-allergic passengers take when flying."
And, to be clear, passengers with food allergies should continue taking measures to protect their health, the study's authors advise.
But the research suggests that asking other passengers to abide by an in-flight nut ban is not gonna help.
The part of the plane people with nut allergies should worry about
"The most effective measure" for avoiding an allergic reaction, per the study, "is for passengers to wipe down their seat area" thoroughly when boarding. That includes the tray table and seat-back screens. "Food proteins are often sticky and adhere to these surfaces, from where they are easily transferred to a person’s hands and onto food that might be consumed," the researchers write.
The previous occupant of your seat might have eaten something you're allergic to, in other words, and that person could leave behind toxic-to-you residue that wasn't adequately removed between flights.
So other passengers can still be a danger—but from coming into physical contact with their peanut dust rather than breathing it in.
That's why it's important for passengers with nut allergies to board planes early, study coauthor Paul Turner told the BBC, so that those travelers "have time to clean their seat area with something like a baby wipe or antibacterial wipe."
Most airlines will accommodate an early-boarding request from passengers with food allergies for that reason. You simply have to notify the carrier in advance.
The policy of Delta Air Lines, for instance, is to allow pre-boarding for those with allergies (if requested) to wipe down their seats with sanitizing wipes. If notified in advance, the carrier is also supposed to refrain from serving certain food products during your flight or assist with seat changes to prevent an allergic reaction.
Those provisions are pretty standard across the aviation industry, though news stories do periodically arise involving passengers encountering less-than-accommodating flight crews or having severe reactions to meals they shouldn't have been served.
In case things go wrong, passengers at risk should travel with a doctor-prescribed epinephrine autoinjector (EpiPen) in their carry-on belongings, the authors of the allergy study say—and, they add, airlines should be more consistent about stocking EpiPens in onboard medical emergency kits.
That would be a lot more helpful than simply ordering other passengers not to eat nuts during the flight, which could, per the study, instill a "false sense of security."
