As if we needed another reason to wash our hands.
Two enterprising teachers have given their students living proof of the importance of hand washing in one stomach-churning classroom experiment involving moldy bread.
In the end, they found that good old-fashioned hand washing was even more powerful than using hand sanitizer.
The Idaho Falls, Idaho, teachers wrote about their gross experiment earlier this month in a now-viral Facebook post with over 64,000 shares.
“It was a doozy,” says Jaralee Annice Metcalf, a behavioral specialist at Discovery Elementary School, who led the experiment with teacher Dayna Robertson.
“We’ve noticed a lot longer lines in the bathroom for hand washing,” Robertson tells The Post.
The investigation, which began in mid-November in their special education class for kindergarten through sixth-grade students, involved five slices of white bread, one of which was left untouched and immediately zipped into a plastic bag: the control slice. The other four were handled by all 17 students plus both instructors, but in various states of cleanliness.
“We took another piece of bread and passed it around … Everybody had [just] eaten lunch and come inside from recess,” says Robertson, 38, who had learned about the experiment on Mystery Science, a website for teachers to share science lessons.
“We went and washed our hands with soap and water and [passed around] another piece of bread.”
After waiting a few hours, allowing time for germs to re-collect on the kids’ hands, they each took a squirt of hand sanitizer. Another piece of bread then made its rounds, with each child gently palming the slice and passing it to their classmate.
The last slice was wiped across the keyboards of their classroom Chromebooks — which are normally cleaned daily, but were left unsanitized for this exercise.
Each slice was dropped in a plastic bag, labeled, and hung on the classroom wall. It was about two weeks later, according to Roberston, that they started to see mold growth. At that point, the class took their Thanksgiving break.
After that, says Robertson, “It just exploded.”
“I don’t even think we expected it to look so drastic,” added Metcalf.
The revolting results were “a big surprise” for the class, according to Robertson. While they assumed that the unwashed hands sample might be the most vulnerable to mold, it turned out that the bread rubbed on the Chromebooks turned the blackest and fuzziest of all.
They also didn’t expect to learn that hand washing would be the most effective means of battling bacterial growth, as opposed to hand sanitizer. Shockingly, the bread handled post-gel appeared to harbor at least two different strains of both black and yellow-colored mold.
Metcalf thinks the problem with antibacterial gels, which allegedly kill 99.9% of germs, may be from improper use.
“Kids don’t use hand sanitizer … the way it’s supposed to be used,” she explains, which requires rubbing their hands together for a full 20 seconds, as recommended by the Centers for Disease Control and Prevention.
Word of their alarming assessment spread like a virus. Soon teachers throughout the school came to the classroom with their own students to give “mini-lessons” on proper hygiene using the moldy bread as an example.
Their demonstration yielded even better results than they’d anticipated.
“We have students that will just pop up randomly and be like, ‘I’m gonna go wash my hands,’ and just walk out of the classroom,” says Metcalf, who’s not complaining about the interruption. “We’re like, ‘OK, that’s a good idea!’ ”