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What Is Cross-Contact vs. Cross-Contamination? [W/ Examples]

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What Is Food Cross-Contact?

Food cross-contact happens when your allergen comes into contact with another food that is not your allergen. Due to this, each food then contains trace amounts of the other food, likely amounts that are undetectable. It’s important to understand how serious cross-contact can be, it’s the same as ingesting a life-threatening food allergen, because even tiny amounts of food protein can cause reactions in people with food allergies.

The Dangers Of Sneaky Cross-Contact

Being severely allergic to a food, people assume that most settings are safe, and that moving through life being mindful of what I eat is my main focus… wrong! At least in my experience, cross-contact is a much larger and difficult part of my food allergy to control.

What Is Cross-Contact vs. Cross-Contamination?

Based on my research, the term “cross-contact” is fairly new. Meaning, within the last decade it has become the most common term used when food allergen contamination occurs. Some people may call this “cross-contamination” by mistake, because they both sound interchangeable. Technically speaking, they aren’t.

I’m guilty of confusing the two and interchangeably using ‘cross-contact’ and ‘cross-contamination’, but this FARE article explains, “Cross-contamination is a common factor in the cause of foodborne illness. Microorganisms such as bacteria and viruses from different sources can contaminate foods during preparation and storage. Proper cooking of the contaminated food in most cases will reduce or eliminate the chances of a foodborne illness.” You still may catch me using the two interchangeably by accident, like many do, and that’s just because it’s confusing to me since cross-contact causes contamination of surfaces. Regardless of the terms being used, I think we all get the point, the surface has been contaminated with an allergen.

Allergen Particles Linger

Being allergic to the dust and trace particles of my allergen, too tiny to be seen with the naked eye, is the trickiest part for me. Deadly particles are quite literally almost everywhere and they spread extremely easily, and we have no way of knowing if they’re there. It would be convenient if allergen particles could be killed or destroyed with alcohol or bleach, instead, food particles tend to really linger and can contaminate surfaces indefinitely. For example, say I sat on a public park bench where someone unbeknownst to me was shelling peanuts an hour before I got there and sat down. I could walk back to work, sit in my office chair, contaminating that surface without realizing it, and then hours later put something in my back pocket, touching the pants covered in peanut dust, and then touch my face and that count ignite a severe allergic reaction. The trace amounts are hard to trace. Often I don’t know why I’m reacting, but have to trust that it is due to cross-contact.

Examples of Cross-Contact Out & About

Piggybacking off my earlier blog post on pet related cross-contact, I’ve learned that not only homes and vehicles of friends and family with pets are contaminated, but the entire world is covered in peanut dust, and that isn’t even an exaggeration! There’s just no way to control minuscule amounts of particles and completely remove them from an area. It’s reasons like this that I appreciate the gesture that my local Baseball Stadium tries to accommodate those with peanut allergies by having a peanut-free day each year, but with being so allergic and reactive, I don’t feel comfortable taking the risk of attending when I know they serve peanuts every other day of the year! Even the most skilled staff I don’t believe could fully clean the space – I think of all the doorknobs, restroom surfaces, water fountain handles, railings, floors, the surfaces in the food and beverage areas… are they really cleaning everywhere?! I’m skeptical & I have to be since my life depends on it.

Cross-Contact In Food Production

Thinking about cross-contact from a commercial kitchen or food manufacturing standpoint, if the allergens are present in the facility, they’re potentially ending up as trace amounts within the final product. Take a look at my photo of my Trader Joe’s salt below, I was shocked to see soy being a possibility in table salt! This is in no way a diss to Trader Joe’s, this transparent labeling is great, people need to be aware of allergens and the risk at the facility level. In fact, Trader Joe’s has a phone line I rely on heavily and am so grateful for (phone number attached below), and it is surprising to learn about the various food allergens packaged on shared equipment as other completely unrelated food items. One coming to mind is my favorite Trader Joe’s jam is made on shared equipment as anchovies!

trader joes salt

In the United States, calling 626-599-3817 will get you through to a Trader Joe’s representative who can tell you what allergens are in the facility and on shared lines with any Trader Joe’s brand product. You’ll just need the barcode! Find other helpful food allergy resources here.

I’ve even seen a bag of kiwis at Kroger labeled “may contain peanuts”. I assumed they were bagged on shared equipment, and was so happy they disclosed that so people can avoid if they’re highly allergic or be sure to wash them extra well, or not purchase them– whatever your comfort level is.

Cross-Contact In Restaurants

I understand the risk of my actions when I am dining out at an establishment that isn’t certified allergen-free, because I’m unable to know the same information about products and their facilities. I can’t know about cross-contact at the same level in a restaurant that I can when I’m doing my own shopping at the grocery store and cooking at home, because I’m not able to email and call on each individual ingredient before ingesting them. However, if I talk to a restaurant and feel comfortable taking the risk, I will occasionally eat at local restaurants, or transparent restaurants such as: Olive Garden, Chipotle, and Taco Bell, where they have the top allergens listed online, and I can verify that there aren’t at least peanut products on the menu and used in the kitchen right then. When restaurants list food allergy information online, it is very helpful to gauge risk level, so that I know the chances are somewhat less, potentially. Like I mentioned, I will also eat at non-chain/local restaurants in our area or when traveling after I’ve emailed with them about what is in their kitchen. I ask if they use peanut ingredients such as peanut oil, peanut butter, or peanuts in their kitchen, but I still personally limit my going out to restaurants overall. Unless they’re allergen-free certified, like Annie Mays Sweet Cafe!

3 Common Ways Cross-Contact Can Occur

Even places that don’t use peanuts, it is still a risk for me to eat there for many reasons, here are 3 common ways cross-contact could still occur and cause a life-threatening reaction:

  1. An employee working could be eating something with my allergen and handling the food, contaminating surfaces, silverware, my napkin, etc. I’ve seen employees out on smoke breaks smoking and snacking, so it isn’t unlikely.
  2. More likely, the individual ingredients the restaurant is using could be made or packaged on shared equipment as peanuts without them even knowing, so asking them if THEY use peanuts in the restaurant isn’t guaranteeing that peanuts aren’t in the facility where the individual ingredients are coming from such as salsa, tortillas, pasta, cheese, flour, etc.
  3. Someone sitting at my table in the restaurant before me could be covered in peanut dust/particles and contaminate my table/chair, if I touch the table then my face, it could be enough to ignite a reaction.

So, Yeah, Cross-Contact Is Scary & Unpredictable 

Cross-contact can come from a million various situations. In kitchens, both in-home or inside a restaurant, it can come from dishes with peanut residue on them contaminating all the other plates/utensils, the preparation of food in the same areas, or shared pans and ovens! The particles can get on hands, cabinet doors, in the pantry on items, literally anywhere you touch or go.

One time I was at Qdoba, this was back before they put up signs saying, “everything here may contain common allergens like peanuts, tree nuts, shellfish, milk, and so on” — eat at your own risk, basically. While I was there I saw a customer eating a snickers bar inside at a table. Not long after that, I saw someone eating Qdoba while their child was playing with their peanut M&Ms organizing them by color on the outside tables. This could very well have been the same table I later go to sit at, or person I’m next to, causing me to have an airborne or cross-contact related reaction. It wouldn’t be an overstatement to say that every day I see AT LEAST one situation that could put me in danger, just from me touching something or being around a cross-contact contaminated area.

Work-Related Cross-Contact Example

To give a work-related example, which I also cover in my post on peanuts at the workplace, I know a few people who eat their peanut products outside, because they aren’t allowed to have them on my floor at work since my building is peanut-free. I greatly appreciate that, because it does limit dust in the break room, bathroom, and common areas, and then there’s the whole airborne aspect as well. Although, twice now, I’ve seen someone eating a small bag of peanuts outside in a common area in front of my building, then wiping their hands on their pants and opening the front entrance door handle, pressing the ‘up’ elevator button, and using the door handle to get into my floor. The last time I witnessed this, I waited 5 minutes, debated what to do and if I should cover my hand in my clothing instead of touching it directly. Instead I found a piece of paper on the ground (which honestly could’ve also been contaminated, who knows!) to use it as a barrier between the peanut dust and my bare hand, and walked inside trying to hold my breath as much as possible, and immediately went threw away the paper and washed my hands afterwards. There’s no getting around allergen particles traveling from hand-to-object (aka cross-contact), and it’s just a part of life I have to be cautious of.

Cross-Contact In College

Lastly, I’ll share a story about a peanut reaction I had in college while giving my — super important — senior presentation. At my college they kept the rooms I was in peanut-less, but the entire campus was not peanut-free. I was sitting in a room with 4 other students, presenting to two professors, and the stakes were high. Suddenly I started to feel my face get really hot and my lip itchy and swollen. I had already presented, thankfully, and was sitting in one of the leather office chairs sitting around an oval table. I’m sure earlier before presenting I was going over my presentation in my head and touching my face nervously. I looked down in the back of my seat to check my surroundings and try to reassure myself it was probably nothing, and it looked as if someone had eaten peanuts in my chair! There were a few actual whole peanut pieces around the back seat crease.

In shock, I hesitantly interrupted the other student presenting, to let them know I needed to leave immediately because of my chair. They were equally as shocked and horrified. It was absolutely not intentional, I was a part of the discussion when we randomly chose the office, and I even chose my own seat. It was a complete fluke, and something I now am on the lookout for in shared spaces!

I’ve been inside a friend’s car before who warned me they’ve eaten peanut products in there recently, potentially wiping their hands on the seat or shared spaces as the passenger’s side. I love knowing this information, it’s helpful for me to know, so I don’t touch my face, and know to shower once home and put my clothes directly into the laundry. My friend Laura once lost a peanut in her car for over a week, and she would not let me in it until she found it! All this to say, I appreciate being in-the-know about anything peanut-related you’ve eaten if it may impact me, because cross-contact is not to be handled lightly and can be just as serious, and deadly, as ingesting the allergen.

Final Note: An Eye-Opening Cross-Contact Statistic

In general, life is peanut-y. You’d never notice unless you needed to, or until it’s brought to your attention. For now, that’s all for my hopefully informative rant on daily encounters with cross-contact! Like I’ve said before, this is a subject I will touch on likely in each blog post, since it’s such a huge part of having a severe and airborne allergy. 

I’ll leave you with one eye-opening statistic I learned recently– each peanut kernel contains about 300mg of peanut protein, and research has found it has taken only 1mg to put someone into deadly anaphylaxis. Meaning, each peanut contains 300x the amount of the allergen known to have sent someone into a life-threatening reaction. I go into more detail about this in my free PDF on food allergies and cross-contact 101 & the website FARE has an article with many resources and FAQs related to cross-contact and cross-contamination.

                   XO Zoë

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