I believe it was Consumer Reports but may have been another highly respected source that did a report on bottled water. Tap water in many areas of the US tested better than bottled. In Mexico my aunt - who lived there for 35 years - said they probably just fill the bottles from the tap. You can search and Google online to learn more about bottled water. The proper system will provide better water and we have tested it as such. CR tested one of the most well known brands as having unacceptable levels of arsenic. I know water from our system is safe. I do not know that all bottled water is safe.