Ah, the creepy part. That bottle cap you twisted off with your grimy hands? You just invited bacteria to the party. Once you open a bottle, your mouth’s microbes—and any airborne dust—start having a field day.
Tap water has chlorine to keep bugs at bay for a while. Bottled water? Not so much. It’s filtered, but it’s not sterile.
Can Water Go Bad In A Thermos at Doreen Woods blog
If you backwash (yes, you know what you did), you’re feeding a tiny ecosystem. Let that bottle sit for a few days at room temp, and you’ve got a petri dish you didn’t ask for.
Expiration Dates Are a Thing
Ever notice a “best by” date on a water bottle? That’s not because the H2O expires. It’s because plastic degrades over time, and the company wants you to drink it before the taste gets weird.
Most brands give you about two years from bottling. After that, the plastic may start to flake (microplastics, anyone?) or the carbonation (if it’s sparkling) goes flat. Flat, warm, plasticky—sounds like a party, doesn’t it?
Plus, the FDA requires expiration dates on bottled water, even if it’s a bit overkill. They’re covering their butts. Fair enough.
