Tap water can contain bacteria. It is not suitable for use in a neti pot or any other flushing device. Interestingly, the group that drank the hot beverage reported greater subjective relief from cold symptoms compared with the other group. You can email the site owner to let them know https://www.linkedin.com/feed/update/urn:li:share:7356320248985194496/?actorCompanyId=77283885