A scientist has revealed the sickening reason why you should never use a hand dryer in a public toilet and always opt for a paper towel.
An experiment by a scientist who goes by Devon Science on TikTok exposes how many bacteria lurk in machines, which are sprayed onto freshly washed hands.
The video, which has racked up 4.7 million views, shows the scientist placing a Petri dish under a dryer and collecting the bacteria that sprout.
To make the test fair, he also collected bacteria from the atmosphere in his lab and left both samples overnight.
The next day, the petri dish with the germs from the hand dryer showed a variety of different bacteria and fungi spread throughout the dish, appearing in white, yellow, and black spots.
However, the plate that was waved in the air (to imitate someone drying their hands with their hand) remained completely clear.
He admitted that’s why he avoids using hand dryers and instead opts to use paper towels or shake his hands to dry.
An experiment conducted by a scientist who goes by the name Devon Science on TikTok exposes how many bacteria are hiding in the machines, which are sprayed on freshly washed hands. In a video that has accumulated 4.7 million views on the social network, the scientist is shown turning on the dryer over a Petri dish to discover which bacteria would grow.
For the next part of the experiment, Devon Science applied toilet paper (which it previously used to dry hands) on a Petri dish.
While this also produced a variety of bacteria, it was much less than the hand dryer.
Finally, he cleaned the interior vent of the dryer, which was so dirty that the cotton swab came out black.
The results again showed a Petri dish filled with different types of bacteria, similar to the insects that come out of the blower.
Following the stomach-churning results, Devon Science said: “Now I know where the bacteria came from, they actually live inside the machine.”
While the lab scientist did not reveal which specific bacteria were captured, previous research shows that E. coli, hepatitis and bacteria found in feces lurk in public bathrooms.
Previous studies have also suggested that hand dryers can shoot bacteria onto people’s hands when they suck in the air around them, where the microorganisms can linger.
The scientist compared bacteria directly from the hand dryer, toilet air, and dryer inlet vent. He found that the dryer plates contained the most bacteria.
one 2018 studyconducted by researchers at the University of Connecticut and Quinnipiac University, tested whether hot-air hand dryers in public bathrooms absorbed bacteria from the air and dumped them on freshly washed hands.
The researchers exposed a Petri dish to hot air from a bathroom hand dryer for 30 seconds.
They identified up to 254 colonies of bacteria sprouting inside the pot.
They then placed high-efficiency particulate air (HEPA) filters in the hand dryers to prevent airborne bacteria from passing through the dryer.
When they repeated the test they found that the amount of bacteria on the dishes had decreased by 75 percent.
This suggests that most of the bacteria sprayed by hand dryers comes from the air in public bathrooms.