Chris, <br>I agree about the puzzle of buying bottled water. Without any refereces to guide me, I would think that the guardian filter system with the viral protection module or boiling would eliminate any bacterial or viral threat. Keep in mind that water really needs to be at a rolling boil, not just hot to kill microorganisms.<br>Chemical agents are just chemical contaminants that may be removed by charcoal filtration (SWAG).<br>I will look into this and see if I can answere the question more fully.<br><br>Jeffery S. Anderson, M.D.<br><br>