Some information for those who might be overly-paranoid all of a sudden regarding this “green slime plague” that has been inserted into the collective brain.
Can You Clean Coronavirus Off Your Food?
Since the COVID-19 outbreak began, I’ve covered advice for how to effectively clean your hands and disinfect surfaces around your home, but what about food, like takeout and fresh produce? Could eating contaminated food cause you to contract the illness?
According to News Channel 8,1 Virginia police are “warning of a ‘disturbing trend’ after a group of teens were caught on camera coughing on produce at a grocery store, then posting it on social media.”
Shenanigans like this appears to be behind some of the fears and warnings about food contamination that are now in circulation. In a March 19, 2020, Facebook post, Purcellville police stated:2
“We are asking for parental assistance in monitoring your teenagers’ activities, as well as their social media posts to avoid the increase of any further such incidents.”
Conventional Food Safety Rules Apply
The good news is, evidence suggests there’s little cause for concern, provided you follow conventionally accepted food safety guidelines. As noted by the U.S. Food and Drug Administration:3
“Unlike foodborne gastrointestinal (GI) viruses like norovirus and hepatitis A that often make people ill through contaminated food, SARS-CoV-2, which causes COVID-19, is a virus that causes respiratory illness. Foodborne exposure to this virus is not known to be a route of transmission.”
Similarly, in a March 14, 2020, article in The Atlantic,4 epidemiologist Stephen Morse from Columbia University noted that “cooked foods are unlikely to be a concern unless they get contaminated after cooking,” and that holds true even if the person preparing the food is ill.
The reason for that is because high heat kills most pathogens, including coronavirus. Ideally, a sick person would not be doing the cooking for others, but even if that were the case, or in cases where you might not know you’re a carrier, the sensible thing to do is to make sure you don’t cough or sneeze on or near the food.
In “Food Safety and Coronavirus: A Comprehensive Guide,”5 J. Kenji Lopez-Alt, chief culinary adviser for Serious Eats, answers a range of food safety related questions based on what is currently known. Importantly, there is (as of yet) no evidence of transmission of COVID-19 via food or food packaging, according to the FDA.6,7
Food Packaging Is Not a Suspected Disease Vector
While preliminary findings suggest the virus can remain viable on cardboard for up to 24 hours, and stainless steel or plastic for as long as three days,8 if we are to believe the CDC,9 the risk of contracting COVID-19 by touching contaminated surfaces and then touching your eyes, mouth or nose is minimal — at least far lower than droplet infection (meaning you inhale the airborne virus).
“It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this is not thought to be the main way the virus spreads,” the CDC notes.10
As suggested by Lopez-Alt,11 a sensible way to minimize any risk associated with contaminated food packages, however potentially small, would be to transfer the food to a clean container and wash your hands with soap and water for 20 seconds after discarding the original container.
Cooked and Raw Food Are Unlikely Sources of Infection
As mentioned, heat will kill any pathogens present in the food being cooked, and reheating takeout is one avenue you can take if you’re concerned. Research12 on SARS-CoV-1 (the virus responsible for SARS) found the virus was inactivated by temperatures above 149 degrees F (65 degrees C) after three minutes, and preliminary evidence13 suggests SARS-CoV-1 (COVID-19) is highly sensitive to heat.
For reheating and heat-sterilizing recommendations, see Lopez-Alt’s article, “Food Safety and Coronavirus: A Comprehensive Guide.”14
Raw food is also unlikely to cause COVID-19, even if it’s contaminated by a cough or sneeze. The reason for this is because respiratory viruses such as SARS-CoV-2 reproduce in your respiratory tract,15 not your digestive tract, which is where your food goes. The two are separate.
And, while the SARS-CoV-2 virus has been found in feces, there’s no evidence suggesting it can cause illness by going through the digestive tract. Nor has there been any reports of fecal-oral transmission of COVID-19 (which could occur if a food handler fails to properly wash their hands after going to the bathroom), according to the CDC.16
Also keep in mind that viruses require a live host, and cannot replicate and multiply on food. Rather, the viral load will decrease over time. Even eating contaminated food with your bare hands is unlikely to cause a problem. Lopez-Alt writes:17
“What about this scenario: a worker coughs on a cutting board then assembles a hamburger directly on that board before placing it in a takeout container. You then come home and eat that burger with your bare hands, then pick your nose, or do something else that deposits the virus along your respiratory tract.
In this situation, the viral load has been diluted several times. First when it was transferred from the board to the burger bun. Next, more viral load was shed when the bun was placed in the takeout container. It is diluted again when you pick up the burger before interacting with your face in inadvisable ways.
While he didn’t rule out the possibility of picking up the disease this way, [North Carolina State University food safety specialist Ben] Chapman described it as ‘a moonshot, even before you touch your face.’ Using clean silverware when possible and washing your hands after eating and before touching your face further minimizes that risk.”
Avoid Washing Produce With Soap
All of that said, it’s still advisable to wash your produce before cooking or eating it raw. As noted by People magazine,18 soap — while effective for killing viruses — is not appropriate for most fresh produce, although you could use it for some things. Francisco Diez-Gonzalez, director of Center for Food Safety at the University of Georgia, told People:
“Using soap has never really been recommended for fresh produce before, and our recommendation has still been to use water and rinse … I don’t have any evidence that it will for sure reduce risk of the virus because we don’t have the research.
There is almost no evidence that implicates that food as a vehicle for causing this disease. The evidence we have is still largely person-to-person transmission.”
Similarly, infectious disease expert Dr. William Haseltine, president of ACCESS Health International, told the magazine, “I wouldn’t wash your lettuce with soapy water, but something like a potato or an apple or a plum you can wash, the outside of a mango you can wash.”
Also keep in mind that while it may seem innocuous to add a few squirts of hand or dish soap to your produce with the intention of removing pathogens, of the 232 hand-washing detergents listed on the Environmental Working Group’s (EWG) Healthy Cleaning database,19 58 scored a failing grade. Examples of toxic ingredients found in dish soap include:20,21
|Cocamide DEA — Suspicions include cancer, chronic aquatic toxicity, acute aquatic toxicity.|
|DMDM hydantoin — Suspicions include chemical release of formaldehyde and irritation of the skin, eyes or lungs.|
|Ethanolamine — Suspicions include respiratory effects, general systemic/organ effects, chronic aquatic toxicity, nervous system effects, skin irritation/allergies/damage.|
|Formaldehyde — Suspicions include cancer, general systemic and organ effects, skin irritation/allergies/damage, acute aquatic toxicity.|
|Sodium borate — Suspicions include developmental, endocrine and reproductive effects, skin irritation, allergies and damage, and respiratory effects.|
|Sulfuric acid — Suspicions include cancer, respiratory effects, skin irritation and allergies.|
|Triclosan — Suspicions include aquatic and general ecotoxicity, developmental, endocrine and reproductive effects, cancer and immune system effects.|
What About Bleach?
Washing your produce with bleach is another tactic that is likely unnecessary, and may react with the organic material in the food to create disinfection byproducts that are far more toxic than chlorine. As reported by MSN,22 “experts advise against putting bleach on anything you’re going to eat … and say washing with warm water works just as well with fewer potential risks.” The article continues:
“In a recent New York Times California Today newsletter, a food safety expert suggested that Californians facing ‘shelter in place’ orders should take extra precautions when making essential trips to the grocery store.
This advice includes tips on how to sanitize grocery items, including using a very diluted bleach solution (one teaspoon of bleach per gallon of water) to mist produce, and then let it air dry before eating.
Other experts say this isn’t necessary, and may not even be safe. It’s unlikely that you’ll be infected by the virus via your groceries, according to Dr. Tamika Sims, the Director of Food Technology Communications at the International Food Information Council …
Bleach could … present health risks of its own. Food safety guides23 advise against using bleach or detergent on anything you’re going to eat. ‘Bleach is not meant to be used to clean any foods or food products. The ingestion of any amount of bleach can be a major health hazard,’ Sims said …
If you are concerned about your fruits and vegetables … just cook them, or wash them thoroughly with warm water … ‘CDC has told us that this virus denatures (breaks down) relatively easily with warm water and with heat,’ she said.”
How to Wash Your Produce
Speaking to Delish.com, CarrieAnn Arias, VP of marketing at Naturipe Farms says:24
“Washing your fruits and vegetables under running water is always recommended, even if it has a peel you will be discarding like our avocados. Don’t use soap, detergents or bleach solutions. When it comes to berries, you will want to rinse in cool running water before serving.
Raw veggies and fruits are safe to eat, especially right now. They are packed with nutrition and essential vitamins that can aid in boosting our energy and immune system.”
Ken Rubin, chief culinary officer at Rouxbe culinary school, echoes Arias’ advice, saying:25
“The best practices for washing fruits and vegetables has not changed or been revised in light of the COVID-19 pandemic. The same principles that have always been true still apply. If you are uneasy or uncertain, just buy varieties of produce that you can either peel at home (like bananas, oranges, mangoes or avocados) or choose products that you will cook.”
Those “best practices” are simple indeed, and just like Arias points out. As explained by Barbara Ingham, a food science extension specialist with the University of Wisconsin-Madison:26
“Wash all whole fruits and vegetables before preparing them — even if the skin or rind will not be eaten. This prevents pathogens from being transferred from the rind or skin to the inside of the fruit or vegetable when it is cut …
Wash fruits and vegetables under clean, running water in a clean sink. Fresh fruits and vegetables should not be soaked in water. Do not use detergents, soaps or bleach to wash produce. These products may change the flavor and could be poisonous.
If the fruits and vegetables are firm (such as potatoes or melons), scrub them with a clean, sanitized fruit/vegetable brush. For soft fruits and vegetables (tomatoes), gently rub them with your hands to loosen the dirt. Also remove the outer leaves of lettuce and cabbage before washing them.
To wash berries, parsley and greens, put them in a clean colander and spray them with a kitchen sink sprayer. Or, gently turn the produce as you hold it under running water. Be sure to turn and gently shake the colander as you wash the produce.”
Can You Use Vinegar?
A safe alternative that can help reduce your exposure to foodborne pathogens — but not likely viruses — is to wash your produce with white vinegar and water in a 1 to 3 ratio. Let the produce rest for 30 minutes and then wash lightly under cold running water.27
The acid in the vinegar can cross bacterial cell membranes, killing the cells,28 but research suggests it doesn’t provide much protection against viruses. As noted on Talk CLEAN to Me, a blog by experts in chemical disinfection for infection prevention:29
“… organic acid disinfectants … typically lack a broad spectrum of kill … You may be thinking ‘Hey, wait! Vinegar and acetic acid have been used for hundreds of years as methods of disinfection and sanitization.’
However, it is important to note that these only show strength against relatively easy to kill organisms such as pseudomonas. There is no current data that concludes that organic acids bolster a broad spectrum of kill.”
One type of vinegar that does appear to be effective against viruses is malt vinegar (made from malted barley grain, which is also used to make beer; a second fermentation turns the ale into vinegar30).
According to the 2010 article, “Effectiveness of Common Household Cleaning Agents in Reducing the Viability of Human Influenza A/H1N1,” published in PLOS ONE,31 10% malt vinegar “rapidly and completely” inactivates influenza viruses.