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    This PhD Student Is Going Viral After Revealing How Much Bacteria Can Be Found In Grocery Stores, And I'll Never Be The Same

    Try not to be shocked!

    Now more than ever, many people are curious about what germs may be lurking in public spaces. Due to COVID-19, some think twice before grabbing, for example, a shopping cart’s handle before wiping it down. But is that necessary? Experimental medicine and parasite vaccinology PhD candidate Dilhan Perera has taken to TikTok to illustrate just how much bacteria is actually lying around grocery stores.

    In a massively viral video that has now been viewed over 3.1 million times, the 25-year-old student swabs and tests commonly touched items for bacteria, including: apples, milk cartons, meat packages, freezer door handles, shopping cart handles, and a card reader at self-checkout.


    GROCERY STORE BACTERIA!!! #learnontiktok #microbiology #bacteria

    ♬ Mission Impossible (Main Theme) - Favorite Movie Songs

    Afterward, Dilhan stored the samples in an incubator at 37 degrees celsius for 48 hours to see what would grow.

    With the help of lab equipment, the bacteria found can be viewed in individual colonies. For those who, like me, are not microbiologists, a bacterial colony is basically a group of bacteria that comes from a single mother cell. The mother cell is able to reproduce genetically identical cells, and yay, it's a whole dirty party filled with thousands of bacteria cells that present themselves as these little droplets.

    An arrow pointing to a single bacterial colony

    "By looking at the growth of bacteria on plates, we can visualize microorganisms around us that we normally can't see," Dilhan told BuzzFeed. "Everything around us is covered in microorganisms. By counting colonies of bacteria that grow on plates, we can get an idea of how much bacteria are on certain items, as each colony arose from one individual bacterial cell. This shows us that some surfaces or products may be more contaminated or more likely to harbor bacteria than others."

    Ready or not, here are the final results:

    Apples: 32 Bacterial Colonies

    TikTok: @ta.dil / Via

    "Both the CDC and FDA recommend washing fruits and vegetables with water to prevent food-borne illnesses," Dilhan shared. "This is because produce can be contaminated with microbes like bacteria and parasites."

    Milk Carton: 2 Bacterial Colonies

    TikTok: @ta.dil / Via

    Meat Package: Over 300 Bacterial Colonies

    TikTok: @ta.dil / Via

    "There is a wide variety of colors, from white to yellow and orange, so we can see a lot of species diversity [on the meat packaging]," Dilhan said. "Raw meat is known to have bacteria that can make you sick, which is why it is important to cook it thoroughly. These bacteria can cross-contaminate with other items we buy from the grocery store and can potentially make us ill if they get into our system."

    Freezer Door: 5 Colonies

    TikTok: @ta.dil / Via

    Shopping Cart Handle: 1 Colony

    TikTok: @ta.dil / Via

    "They seem to be sanitizing effectively," Dilhan said.

    Card Reader: 6 Colonies

    TikTok: @ta.dil / Via

    Before you download Instacart or pack an extra pair of gloves, Dilhan wants to make it clear that his video is not meant to cause alarm. "According to the NIH, less than 1% of bacteria actually make us sick. The takeaway from this video is that bacteria are all around us and people should practice proper hygiene, especially with food."

    Freemixer / Getty Images

    "A lot of my videos can be fear-instilling to some, but truly my goal is just to help people be aware of the microbes that exist around us and be mindful that these germs can sometimes make us ill," Dilhan told BuzzFeed. "In addition to this, I want to demonstrate the research process to help foster trust in science. Some of my videos teach microbiology techniques used in common practice, and others illustrate those techniques in use to show how researchers design experiments to answer scientific questions."

    Freemixer / Getty Images

    For the most part, many in the comments were actually able to stop looking through their fingers in horror and find comfort in the store's cleanliness.

    One person saying, "Well, this wasn't as bad as I was expecting! I was really concerned about the cart, and pin pad. I was surprised it wasn't worse"
    TikTok: @ta.dil / Via

    And others are already waiting for Dilhan's next in-depth look into the world of bacteria on everyday products.

    One user asked, "Can you do a before and after of fruits/veggies before washing and after washing?"
    TikTok: @ta.dil / Via

    You can watch Dilhan's full grocery store results video below:


    YOU WONT BELIEVE HOW MUCH I FOUND 😱 #microbiology #learnontiktok #letsseewhatgrew

    ♬ Mission Impossible (Main Theme) - Favorite Movie Songs

    For more experiments rooted in microbiology, follow Dilhan on TikTok.

    Were you surprised by any of the results? Why or why not? Let us know in the comments.

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