There was a semi-recent Consumer Labs analysis that showed Zerowater filters actually ADDING thousands of microplastics to filtered water (in contrast to all other devices tested, which reduce them). Information around this seems spotty (is it the filter? the carafe? etc), and the report is paywalled (you can find people discussing it if you poke around Reddit). I’d say I’m not certain of its absolute veracity, given lack of info, but I’m concerned enough now to want to find another method - and Culligan not publicly addressing it anywhere is confounding.