Airborne Food Allergens—What’s the Risk?

When we hear stories of serious allergic reactions to food, they often involve someone unknowingly ingesting a food that contains their allergen. Gut-wrenching stories like the grilled cheese that killed a NYC preschooler, the Indian takeout food fatality in England, the woman left paralyzed after ingesting peanuts while traveling in Budapest, and the sesame-related death of a teenage girl after eating a Prèt A Manger baguette at an airport. 

For many of us, these stories hit a bit too close to home.

In these cases, the food was ingested—but what happens when the allergen goes airborne?  

In January, a story about an 11-year-old New Jersey boy rocked headlines after he died from what authorities believe was an allergic reaction from breathing in the steam from fish cooking in the kitchen. 

While rare, allergic reactions to aerosolized allergens do occur. 

According to Dr. John Lee, Clinical Director of the Boston Children’s Food Allergy Program, most airborne reactions probably occur due to particles of protein that rise into the air when food is actively cooked, and then they’re inhaled. “I’ve had patients describe their throat itching while around peanuts, or reported mild reactions on airplanes, but most airborne reactions typically result from particles of protein rising off heated foods.” For example, he offers someone with a shellfish allergy walking into a seafood restaurant, or a wheat-allergic patient standing near boiling pasta.

According to the American Academy of Allergy, Asthma and Immunology, exposure to airborne food allergens does not typically result in anaphylaxis; however, these airborne particulates can cause symptoms such as itchy eyes, a runny nose, a cough, congestion, and difficulty breathing.

Airborne food particulates can also trigger two forms of occupational asthma: 1) baker’s asthma, following exposure to powdered allergen substances such as dried egg powder, soy flour, or wheat flour during baking; and 2) crab asthma, which is caused by dust and fume exposure from steaming, cooking, or scrubbing crab in processing plants. Both forms of asthma are considered allergic diseases because of the role allergenic proteins play in the respiratory response.

Notably, airborne allergic reactions aren’t limited to food. In at least one case, a chemical fragrance was the culprit. After a teenager named Brandon started developing headaches and hives at school, he connected his symptoms to Axe Body Spray. His allergy to the spray worsened, eventually leading to anaphylactic shock. Laws protecting manufacturers like Axe barred disclosure of the spray’s full ingredients list, preventing his family from discovering the allergenic trigger. Brandon had to leave school because of the exposure risks. 

Suffice it to say, airborne allergenic reactions extend beyond food. 

Most reported airborne reactions, however, continue to stem from common allergenic foods. Since peanut is the number one trigger of food-related anaphylaxis, the extent to which peanut particulates pose a risk is a common question in the food allergy community. 

In a 2003 study of 30 children with severe peanut allergies, researchers examined the extent to which inhalation and skin exposure elicited a reaction. For the skin test, one third of children experienced reddening or skin flares after peanut butter was pressed to their skin for one minute. Conversely, no child experienced respiratory symptoms after sitting in close proximity to three ounces of peanut butter for ten minutes.

The topic of aerosolized allergenic reactions has stirred enough controversy among food-allergic travelers that Southwest Airlines stopped serving peanuts on all flights starting in August 2018, and JetBlue does not serve peanuts on its aircrafts.

Food for thought? We think so. Have you experienced an airborne allergen causing an allergic reaction? Please share your experience if so! 

- Meg and the Allergy Amulet Team 

This piece was written by the Allergy Amulet team and reviewed by Allergy Amulet advisors Dr. John Lee and Dr. Jordan Scott. 

Dr. John Lee is the Clinical Director of the Food Allergy Program at Boston Children’s Hospital. Dr. Lee is widely recognized for his work in food allergy, and his commitment to patient health. 

Dr. Scott is an allergist/immunologist and operates several private allergy clinics throughout the Boston area. He is on the board of overseers at Boston Children’s Hospital, and the past President of the Massachusetts Allergy and Asthma Society.