Airports to Rental Cars: Unexpected Places Where Allergens Lurk

By:
in Managing Allergies, Travel & Dining
Published: October 6, 2025
Caroline with her son Alex in an airport waiting area.

Over the years, my family has learned a lot about travel safety. Our son Alex has multiple food allergies, which includes a life-threatening allergy to peanuts. In some ways, we feel like seasoned experts with all the strategies we use to avoid his allergens while traveling. 

However, even with all our experience and preparation, we’ve still come across potential allergens in a few surprising places.

Book Lovers Beware

When Alex was in elementary school he loved to go to the public library to check out books. This was especially fun before a trip – so he could take new and interesting books to read along the way. 

On one occasion, I was busy packing our last-minute items, while Alex flipped through a book he’d selected for the trip. After a few minutes, he brought the book to show me a brownish substance along the top corners of several pages. I was focused on organizing, so I simply said the last child who had the book must have been eating snacks while reading. I went back to packing, then suddenly stopped in my tracks. 

What do most kids snack on in their free time? 

I grabbed the book out of his hands and smelled the top of the pages. Peanut butter! It was smeared onto a handful of pages, right where a person would turn the page. That book did not go with us on our trip, and I returned it to the library in person. 

We never found food inside library books again, so it was likely not a common problem. But we learned an important lesson that day: peanut butter or any food residue can show up anywhere that people share items. So we learned to be on the lookout for allergens, even in the most unexpected places.

Pre-Flight Snack Attacks

Spilled coffee in an airport waiting area.

The second time we came across unexpected allergens, we were traveling again. As we waited at the airport, my focus was on pre-boarding to wipe down the airplane seats. We have learned from past experience that the person who sat in our seats on the plane ahead of us could have been eating peanuts or other allergens. That’s why it’s crucial to wipe them down thoroughly. 

Seated in the gate area, I noticed several travelers working on laptops. They quietly ate their snacks; some dropping crumbs around them. It wasn’t malicious or intentional, but it was still happening. 

The thought occurred to me: What are people doing while they wait for their plane to arrive?  

They snack. They’ll sip coffee. They eat whatever food is for sale in the airport.

Looking around the waiting area, I noticed crumbs on many seats and coffee rings on the small tables where people placed, and spilled, their coffee. Coffee can contain nuts, such as hazelnut and almonds, as well as dairy or soy milk. 

There was no way to know for certain what the various crumbs were. However, with the sheer number of peanut products for sale at the airport, there was a good chance of peanutty crumbs. 

The realization hit: We were so focused on the potential allergens on the plane that we hadn’t considered the airport waiting area! The majority of people do throw away their trash after eating. But I’d venture that most don’t think about the crumbs they leave or the allergy problems that spilled coffee could cause. 

At one airport, we witnessed a lady eating peanuts, placing the ones she didn’t want on the seat next to her. To her credit, she threw them away when finished, but peanutty crumbs remained.

Now before sitting at the airport, we find a spot that looks clean, and then wipe it down anyway, including the table. Often, the cleaning wipes reveal residue. 

Not-So Clean Car Rentals

Peanuts placed on a seat in an airport waiting area.

During a family trip to California, I was blindsided by my son’s allergens in what I had considered to be a very safe place. We flew into LAX, then rented an SUV to drive around the beautiful state. The vehicle had been cleaned and detailed, so we tossed our luggage in the back and climbed in, ready to start our adventure. 

While driving on the expressway, Alex, who at the time was in elementary school, dropped one of his pens. It had fallen out of sight. I told him to stay in his seatbelt and we’d get it later. At our next stop, he hopped out and I bent down to reach under the front passenger seat. I located the pen … as well as a small pile of peanuts that had been missed by the car rental agency’s vacuum! 

It hit me: What are common snacks people eat when they rent cars for family road trips? 

Trail mix! Handfuls of peanuts! Peanutty candy bars! Whatever snacks they like!

There is no way to know what people have eaten and spilled all over the rental car before we picked it up. Now, we immediately wipe down rental cars as soon as we are given the keys. We treat them the same as an airplane or an airport waiting area. 

I also check under the seats for leftover foods. I’ve never found another pile of peanuts, but many rental vehicles were not as clean as they appeared at first glance. The cleaning wipes show that it is worth taking a moment to wipe down rental cars, as it’s another example of shared space where food allergens can lurk. 

Bottom Line: Expect the Unexpected 

The joy of travel and pursuing new experiences is for everyone, including those of us managing food allergies. Knowing allergens could be “anywhere” doesn’t have to be scary or a cause to fear the unknown. It simply takes a moment to pause and look around, even in places that don’t seem like there would be an issue.

My family simply follows these easy steps, so we can enjoy our travel adventures while staying safe: 

  1. Have a discerning eye in new environments. We take a moment to glance around our area, looking for signs of food residue or crumbs. 
  2. Have cleaning wipes ready by carrying them in an easy-to-access part of our bags, such as an outside pocket. The goal is to be able to grab them quickly, when needed. I make it a point to buy wipes that can be safely used on seats and tables without causing damage. But they have to be capable of removing food residue and crumbs. 
  3. Once we have done what we can to stay safe, we smile and relax. The only thing left to do is enjoy the trip.  

My family has learned to acknowledge that we can’t predict or control every environment – no one can. It’s made us more flexible and open to new experiences, and even new challenges. If we see an allergy-related issue, we will deal with it. 

One thing I know is true: We won’t hide at home. Our family will continue to go out into the world to enjoy new adventures and create lifelong memories together. 

Caroline Fleur is the author of Destiny and Other Dilemmas, a novel with twists, turns, romance and a dash of food allergy perspective. Her son manages multiple food allergies and EoE, and she is dedicated to raising food allergy awareness.

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