Science

I don't think that's correct. It seems there's a low risk of some chemicals leaching into the contents of a plastic bottle over time - if this concerns you, it's a concern when you keep water in a plastic bottle for a long time, not that the bottle becomes more likely to leach chemicals once it reaches a certain age.

There is the other question of microplastics - these are more likely to be found in water from a water bottling factory that uses plastic than from your tap.