I'm no scientist but ionizing water seems parallel to microwaving food that gives you URP's: Unidentified Radiolytic Products. And I would guess that the potential danger is contingent on the (unknown) content of the water being treated. In other words, nuking some elements may be more toxic than others. I flat don't get this ionizing thing, sorry. I don't like ionizing air purifiers because I wouldn't want to flood the air with ionized, carcinogenic particles. I'm absolutely a novice to water treatments but this seems like somebody forgot to GOOGLE "ionize" and "carcinogen."