Mostly it happens due to the pressure difference between outside and inside. The pressure inside the bottle is less than the atmospheric pressure; hence there is no force to push the water from inside.
As per my opinion it wouldn't increase the pressure on the bottle . A force on the outside of bottle would cause a deformation inside the bottle, hence air volume and pressure also increases.
Magnetic field does not work on the particle trapped in the magnetic bottle, it just changes their direction. It is the velocity of the particle itself and the force in the axial direction which causes the oscillation.
I have a personalized stainless steel thermos, it is perfect for keeping my hot drink hot for long time. Plastic chemicals increase the risk of cancer and interfere with brain development and fat metabolism.
I agree with your points and that’s why I have also refused to drink bottles water not only for health concern but also for good environment. Recently, plastic pollution has been found within freshwater lakes, inland seas and rivers.
Well, this is seems scary, BPA-free does not mean chemical free, but yes BPA is more dangerous than other chemicals. And although the evidence is building against BPA substitutes, more research is needed to assess the effects on human health.