Water contamination is a major problem, but the United States is just beginning to examine it and talk about how to deal with it. There are a huge variety of chemicals in our waters from conventional farming as well as from industry. Even the drugs people consume end up excreted into their feces and become a part of our water supply. Most of these chemicals are not looked for on a day to day basis and there are no mechanisms in place to remove it from the water supply.
A new study published Aug. 9 in the journal Environmental Science & Technology Letters, alerts people to the issue of polyfluoroalkyl and perfluoroalkyl (Perfluroalkyl substances = PFAS) that exceed the recommended safety levels in public drinking water. These chemicals disrupt the endocrine system and cause changes in our hormone levels. Additionally they have been found to disrupt the immune system. They are linked with obesity, high cholesterol and cancer.
You can read further details here.
I use a Berkey water filter and it is what I usually suggest to others. If you check on Berkey's website they make the following statement about PFAS.
"PFAS's fall under the category of PFC's - Perfluorinated Chemicals. PFOA, PFOS, etc. The Black Berkey elements that come standard with our Berkey systems do reduce these contaminates, to an Extreme Degree (in parts per trillion). Testing to back this up does exist and will be released soon."
The one I use is here:
There are probably other water filters as good. This is just the one I have used and find does a good job. I would never want to drink water from a municipal water system without filtering it. Even some country water needs to be filtered. Berkey sells filters for other things and if you have special needs I would suggest checking out their other types of filters. They also have some other sizes of Berkeys.