From the Guidelines
Nut allergies are typically not airborne, and the risk of a serious airborne reaction is extremely low. While severe allergic reactions to nuts usually occur from direct ingestion or contact, the proteins that trigger allergic reactions don't generally become airborne in sufficient quantities to cause systemic reactions. However, in some rare circumstances, highly sensitive individuals might experience mild symptoms like nasal congestion or eye irritation if they're in an enclosed space where nuts are being processed or shells are being cracked, releasing dust particles 1.
Key Considerations
- The allergenic proteins are heavy and don't stay suspended in air for long, reducing the risk of airborne reactions.
- Most allergists advise that people with nut allergies can safely be in the same room as nuts, as long as they don't consume them.
- If you have a severe nut allergy, focus primarily on avoiding ingestion and cross-contamination rather than worrying about airborne exposure.
- Always carry prescribed emergency medication like epinephrine auto-injectors if you have a diagnosed severe nut allergy, as recommended by studies such as 1.
Important Details
- In vitro testing with foods should be remembered that highly sensitive patients might experience anaphylaxis after inhalation (eg, cooking fish) exposure, but this is not typically the case with nuts 1.
- Double- or single-blind placebo-controlled food challenges can be done in patients with suspected food allergy in a medical facility by personnel experienced in performing the procedure and prepared to treat anaphylaxis, but this does not typically involve airborne exposure 1.
From the Research
Airborne Nut Allergy
- The risk of airborne nut allergy is a common concern for people with nut allergy, but there are no scientific reports on severe reactions with airborne peanut allergen 2.
- A study found that allergic reactions to airborne peanut proteins are rare and cannot be predicted by high levels of IgE-antibodies to peanut or Ara h 2 2.
- The same study detected biological active peanut proteins in the air, but in very low amounts, and found that the amount of collected peanut protein decreased dramatically when the collection occurred at a greater distance from the peanut source 2.
- Another study mentioned that air travel poses a concern for individuals with nut allergies, but noted that recent evidence suggests limited airborne exposure to nuts 3.
- There is no evidence to suggest that nut allergy is primarily airborne, and most reactions occur after ingestion of nuts 4, 5.
Factors Influencing Airborne Nut Allergy
- The distance from the peanut source is a significant factor in determining the amount of airborne peanut protein, with greater distances resulting in lower amounts of protein 2.
- The time of exposure to airborne peanut protein also affects the amount of collected protein, with longer exposure times resulting in higher amounts of protein 2.
- The type of nut may also influence the risk of airborne allergy, with some studies suggesting that walnut and hazelnut OIT may be associated with a higher risk of reactions 6.