Risk of peanut allergies from air on planes has been overblown

There is no strong evidence that people with peanut allergies are at risk for severe reactions from other people eating peanuts and from allergens circulating in the air on airplanes. While peanuts are technically a legume, it’s thought these findings may also apply to nuts and other foods that people are commonly allergic to.

People with food allergies may develop symptoms such as rash, nausea, and difficulty breathing after being exposed to the allergen through diet, skin contact, or inhalation. In severe cases, this can lead to a life-threatening reaction called anaphylaxis, which can lead to swelling of the throat, dizziness, and more severe breathing difficulties.

Some airlines have banned the sale of nuts on flights and their staff have posted announcements asking passengers not to eat nuts if they know someone on board has an allergy.

To explore the evidence behind inhalation risks, Paul Turner Focusing on peanuts, the Imperial College London professor and his colleagues reviewed the results of five studies.

One study looked for peanut particles in air samples on commercial flights where snacks were served. The researchers found no problems in nearly all the samples they collected. That’s because the planes are equipped with filters that remove peanut particles from the air before they spread into the cabin, Turner said.

The exceptions were air samples collected immediately around small tables where peanuts were consumed, but the levels of these allergens were low and probably not high enough to cause an allergic reaction, Turner said.

Four other studies looked at allergen levels in the air when people ate or peeled peanuts at home or in a laboratory. They also found very low levels of allergens within half a meter of people shelling or eating peanuts. At most, this can cause a mild allergic reaction, such as tearing, Turner said.

But higher levels of allergens were found on the seats, trays and floors of the planes studied in the first study. Turner said wiping down these surfaces would likely eliminate much of the risk. His team is working with British Airways to make flying safer for people with allergies.

The same results may apply to other allergens, such as nuts, seafood and eggs, Turner said.

“This report summarizes what has been established for many years, which is that peanuts are highly unlikely to aerosolize and pose an airborne risk to passengers,” said Matthew Greenholt at the University of Colorado.