Pick a BPA-free water bottle.
The bottles that your bottled water comes from typically contain bisphenol A (BPA), an environmental estrogen that’s been linked to cancers.
The BPA can leach out of the plastic bottle and into your water.
This is particularly true if it is ever stored in any warm temperatures, which causes the BPA to seep into the water in greater concentrations.
However, there are stainless steel, glass, and even new BPA-free plastics that let you keep your water pure and ready when you are.