Originally Posted By OregonMouse

Note that most metal water bottles have a plastic lining, something avoided in their advertising during the BPA scare. You therefore will be releasing BPA into your water if you try boiling in them!

The stainless bottles by klean kanteen and similar have no plastic liner. You can boil in them, no problem, as long as they are single walled. All the aluminum bottles are lined with plastic.
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