According to me, water bottle manufacturers are permitted to provide an expiry date on the bottle. Try stainless steel bottles and containers, it will also help in maintaining inside water temperature.
According to research, the most toxic plastics are #7, #3 and #6, So you must avoid those, except #1, #2, #4 and #5. If you want to use, then choose #1,#2,#4 and #5, but only for limited use and completely avoid 1, 3, 6, and 7 (polycarbonate).
Whenever you want to purchase water bottle, then make sure that it is PET, BPA free and also avoid this #7 no plastic bottle. As per my personal opinion always prefer glass bottle for healthy life .
I always use glass bottle to drink water, beer. Because glass is safer than plastic bottles and it gives better taste, and also good for our healthy life.
Seriously Dear, I am also not aware of GT bottles, Is these GT water bottles leach harmful chemicals? Currently, I am using Stainless Steel water bottle which is made up of natural elements.
As per my opinion when we keep bottle in the freezer, then there are more molecules present outside the bottle than on the inside, so pressure is more on outside of the bottle as compare to inside.