I do not understand all this heating-consumables-in-plastic-containers stuff that gets bandied about here. Don't people realize that most plastics - especially ones not specifically designed for the purpose - leach into their contents all kinds of agents you don't want to ingest? Hell, even plastics that *are* designed to contain hot food and drink can leach nasty stuff into your chow. This is not nutty, tinfoil-hat-wearing paranoia; this is borne out by scholarly, peer-reviewed data. Within the past couple of years, Bisphenol A has become a buzzword of sorts, but there are many more unhealthy agents out there besides this one alone.
Look; if you are risking dehydration and need to pasteurize water to survive, but all you have is an old soda bottle, then go for it. But doing this by choice, under normal circumstances when other cooking vessels are available is, I'm sorry, sheer idiocy.
Normally I would just let this go, but since you're BPL staff, there are people out there who aren't going think critically, and instead just assume you are an authoritative source... In previous post you wrote,
"Great theory based on the mass media scares, but doesn't happen with PET."
With all due respect sir, before you dispense authoritative-sounding advice, you really should check a scholarly resource. While skepticism of the mainstream media is a healthy trait to have - the media machine has fed the public many a heaping spoonful of BS over the years - just because information is reported by the mass media doesn't automatically qualify it for dismissal. A quick breeze-through of Google Scholar will turn up a lot of material that indicates PET leaches agents that can be/are deleterious to human health. And your implication that, because PET has been in use for some time, it is safe is extraordinarily irresponsible; the list of things originally classified as GRAS, but later shown to be anything but is miles long.
I mean no disrespect sir, but you are wrong. And this advice should not be passed on to others as if it was accurate.