I’m going to order some more test kits to test bottled water and water from a filter system.
Have you done tests of your own?
You can do your own tests using the kits here.
P.S. I am not affiliated with the company that makes these test kits. I will not get any money or anything in return for posting this write up. I just found these test kits to be a useful product.
If you do your own tests post your results here.