You can search the NSF.org certifications here, specifically NSF/ANSI 53 and NSF/ANSI 58: https://info.nsf.org/Certified/DWTU/Listings.asp?ProductFunction=053%

You can search the NSF.org certifications here, specifically NSF/ANSI 53 and NSF/ANSI 58: https://info.nsf.org/Certified/DWTU/Listings.asp?ProductFunction=053%7CPFOA+Reduction&ProductFunction=053%7CPFOS+Reduction&ProductFunction=P473%7CPFOA+Reduction&ProductFunction=P473%7CPFOS+Reduction&ProductType=&submit2=Search https://info.nsf.org/Certified/DWTU/Listings.asp?ProductFunc... https://www.nsf.org/news/pfoa-pfos-reduction-claims-requirements-added-to-nsf-standards https://www.nsf.org/news/pfoa-pfos-reduction-claims-requirem... P.S. Note the "facility" where these products are manufactured are also listed. One might also want to note that [replacement] filters may also have different country origins.