CHARLOTTE — Reusable water bottles can help you stay hydrated, but how often are you washing yours?
WSOC TV’s Erika Jackson met with Brittany Johnson, an assistant professor in UNC Charlotte’s biological sciences department, to find out just how much bacteria we may be carrying around every day.
“The inside may not be that bad,” she said. “Oftentimes it’s the lid and those tiny crevices.”
She used the tools in her lab to swab for bacteria on bottles, lids, and straws.
After disinfecting the testing space, Johnson rubbed a saline solution on the test subject and then wiped the swab on two plates that grow different types of microorganisms. She put the plates in an incubator set to 37º Celsius — the average human body temperature, or maybe the temperature inside a hot car.
Two days later, the results were in.
Johnson said the amount of bacteria in reusable water bottles is usually less than what is found in plastic ones, but the results were shocking nonetheless.
Kelsey Schauf told WSOC that she washes her water bottle daily. Her results came back showing just a few spots of bacteria.
Her husband’s, on the other hand, came back covered in bacteria.
“My husband doesn’t really keep up with it all that great,” she said. “So his cup is his problem, I’ve got mine.”
A tumbler that was rinsed with soap and water, then used once by the owner came back covered in bubbling bacteria.
One WSOC employee said he has never washed his water bottle. Bacteria was nearly covering the test plate.
Johnson said everyone has their own, unique bacteria, so some of these clusters could come from bacteria in the drinker’s mouth. However, some bacteria may come from outside sources.
“When you’re taking your water bottle with you other places, like you’re taking it to the bathroom, then there are germs in the bathroom and bacteria in the bathroom that get on your water bottle,” she said. “Then you ingest those and that can be harmful.”
Johnson said foreign bacteria is the most concerning because it can make you sick.
“You have germs on your hands then you touch the water bottle that would be an example of where you could get more of those harmful bacteria,” she told WSOC.
The makers of Stanley tumblers advise taking apart all removable pieces and hand-washing every part with warm water, soap and a bottle brush.
It is also important to let the parts dry before reassembling.
The most important thing is to wash your bottle frequently and thoroughly.
“Be sure you’re washing those tiny crevices,” Johnson said. “I think it’s important to have the right care for your water bottle.”
There are videos you can watch on proper cleaning methods, which point out all of the little pieces in the bottle you need to remove and clean. All you need to do is search for your particular brand.
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