A visit to the frozen yogurt shop could be hazardous to people who are allergic to peanut.

Research presented at the American Academy of Allergy, Asthma & Immunology (AAAAI) annual meeting shows that levels of peanut allergen on yogurt shop counters were the highest compared to other public settings – by far.

Researchers tested levels of the protein associated with peanut allergy on table surfaces in restaurants, both those that offered unshelled peanuts and those that did not; airline tray tables during flights that served peanuts and those that did not; library tables; and topping counters at frozen yogurt shops.

None of the surfaces were completely free of peanut allergens. Here is the amount of peanut protein found in each setting:

  • Frozen yogurt shop counter: 11,126.7 ng/mL
  • Airplane tray tables after mid-flight service with peanuts: 175.3 ng/mL
  • Tables in restaurants that serve unshelled peanuts: 41.1 ng/mL
  • Airplane tray tables on flights that do not serve peanuts: 13.5 ng/mL
  • Tables in restaurants that do not serve peanuts: .77 ng/mL
  • Library tables: .75 ng/mL

Trace amounts of peanut protein can cause allergic reactions in people with peanut allergy. In case of anaphylaxis, a life-threatening allergic reaction, they should carry two epinephrine auto-injectors at all times.

“Our research shows that peanut exposure in public settings is most likely to occur by contact with surfaces containing allergens rather than by inhalation, even in peanut-rich environments,” says study author Jay Jin, MD, PhD, of the Mayo Clinic in Rochester, Minnesota. “It also reinforces the need for regularly cleaning surfaces, especially for people with a peanut allergy.”