Research by American water filtration company WaterFilterGuru has shown that if a reusable water bottle is not washed properly and regularly, mold and bacteria can accumulate on the surface and inside of the bottle. Swallowing them could theoretically make you sick.
Even the tap water in the kitchen is not sterile. Bacteria naturally grow in still water for a few days after filling the bottle. The longer water is stored at room temperature, the more bacteria will accumulate. Cooling filled water bottles can help limit the number of microbes in that water.
Staphylococcus and streptococcus are among the microbes scientists found in reusable bottles. These bacteria are part of the human microflora but can also cause skin and respiratory infections.
Additionally, the bottle will contain microbes from the environment. If the person does not wash their hands, Escherichia coli bacteria may be present in the bottle.
A study by WaterFilterGuru found that levels of coliform bacteria, such as E. coli, in a regular water bottle were similar to those found on toilet seats.
You may experience intestinal discomfort due to dirty water, and you may also experience allergies if there is mold.
If you don’t wash your reusable water bottle frequently, any bacteria and molds that may be present will multiply and spoil the water you pour.
To clean a reusable bottle, use hot water (temperature above 60 degrees Celsius), pour dish soap over the bottle, lather everything up, and let the bottle sit for 10 minutes. After that, rinse the bottle with hot water and let it dry (it is best to leave it overnight).
If you have been using the bottle for a long time but have not washed it, add a mixture of half vinegar and half water and let it sit for a few days. Then use the cleaning method described above.
Ideally, you should clean your water bottle with detergent after every use, or at least a few times a week.
Source: Ferra

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