You should avoid drinking water left open for a very long time. The water left overnight or for a long period of time in an open glass or container is home to numerous bacterias and is not safe for drinking. You never know how much dust, debris, and other small microscopic particles might have passed into that glass.

Non-potable water is unsafe and not fit for human consumption. When you drink non-potable water, you swallow organisms harmful to your body and expose yourself to a number of water-borne diseases. Waterborne contaminants could be bacterial, viral, parasitic or chemical.

Dirty City Water:

• If the public water supply becomes dirty with germs, boil it.
• Bring the water to a boil. Then keep it boiling for 3 minutes. Reason: Should kill all the germs.
• Could also drink bottled water until the problem is fixed.

But let’s get real: Since it’s your own bacteria, it’s unlikely that you’ll actually get sick. Though no one brags about it, many people sip from used drinking glasses, mugs, and bottles without any ill effects. But it’s certainly not advisable to share your bottle with someone else.

As temperature increases, solubility increases. All of this means that different types of gases are dissolving in your water overnight. The amount of carbon dioxide that dissolves increases the acidity (or lowers the pH) of your water which explains the weird different taste of your water now.

“if you’re leaving a bottle of water in a car for a day, there’s really no risk of any chemicals leaching into the water,” Williams said. “If you left it in a car for weeks at a time, then there’s a small chance that some chemicals like BEP could leach into the water but it’s a very small probability,” Williams said.

two years

Manufacturers design plastic bottles for one-time use only. They can be reused conservatively, provided they’ve not experienced any wear and tear. Swapping out plastic bottles for more permanent solutions, such as bottles made from stainless steel, is better for your health and for the environment.

Some researchers who study plastics recommend against drinking water from plastic bottles that have been sitting in hot places for a long time — such as a car sizzling in the sun — concerned that the heat could help chemicals from the plastic leach into the water.