LOS ANGELES — Peanut exposure in restaurants and commercial airplanes was most likely to happen through contact with surfaces harboring allergens rather than by inhalation, according to study findings presented at the American Academy of Allergy, Asthma & Immunology Annual Meeting.
“Clinicians often make avoidance recommendations without direct evidence of the amount of peanut or peanut exposure in these environments,” researcher Jay Jin, MD, PhD, of Mayo Clinic said in a press release. “We quantified aerosolized and surface levels of Ara h2 – one of the peanut proteins associated with food allergy – in common, public locations hoping to provide evidence-driven recommendations.”
Jin and colleagues collected air samples using personal breathing zone samplers for one hour or large samplers for 15 minutes onto Teflon membranes. The researchers also wiped surfaces with Teflon membranes, at which point, peanut proteins were extracted in phosphate buffered saline and Ara h2 amounts were recorded.
According to study results, during active shelling of peanuts, 1.4ng/mL of Ara h2 was identified in a large sampler collection; however, no Ara h2 was identified in personal breathing zone samples from restaurants in which unshelled peanuts were present in the eating area.
While the air samples did not register a significant amount of Ara h2, table surface samples from the restaurants had an average of 41.1ng/mL of Ara h2.
In their samples, the researchers also reported:
- In restaurants without peanuts in the eating area, 0.77ng/mL of Ara h2 was detected on table surfaces.
- Tray tables of airplanes had an average of 13.5ng/mL of Ara h2 on peanut-free flights; following the mid-flight service with peanuts and 175.3ng/mL of Ara h2 after the mid-flight service with peanuts.
- Library tables averaged 0.75ng/mL.
- A frozen yogurt shop toppings counter had 11,126.7ng/mL whereas a table in the shop had 6.2ng/mL.
“The majority of Ara h2 was generally located on the surfaces in these locations – tray tables, seats, in the restaurants, on tabletops – but we had a really difficult time detecting these allergens in the air,” Jin said in a press conference. “Although people report having potential reactions to inhaled peanut allergens, it does seem more likely that exposure may actually be coming from touching surfaces or accidental ingestion in these settings.”– by Bob Stott
Jin J, et al. Abstract 626. Presented at: American Academy of Allergy, Asthma & Immunology Annual Meeting; March 4-7, 2016; Los Angeles.
Disclosure: Dr. Jin reported no relevant financial disclosures.