Today's inquiry came to us from 'Lacie' who asked, "Hi. We have always used a water filter for our well water because we were told it has a lot of metals in it. Now articles tell us studies say metals may actually be good for us? Does that mean we no longer need our water filter?"
Thank you, Lacie, for that question, and we suspect a number of people have similar thoughts on their mind after reading articles discussing how Zinc and other metals may actually help reduce depression (http://www.scientificamerican.com/article/metals-and-mental-health/).
So... metals are good for us now?
In a way, yes, since the human body DOES require them to function, but keep in mind that not ALL metals serve a purpose in the human body... and SOME metals pose extreme danger to the human body.
As an example, take a look at most multivitamins on the market and you will see that they contain metals like Zinc, Iron, Manganese, Copper, and sometimes even Chromium (the metal made famous by Environmental Activist Erin Brockovich). The human body requires these metals to function properly.
The problem arrives...
Trouble shows up when people ingest too much of the heavy metals that our bodies need. As an example, while the body needs trace amounts of Chromium to function correctly, ingesting too much Chromium may result in unwanted health problems such as cancer of the lungs and/or respiratory tract, kidney problems, and in some cases gastrointestinal unpleasantness such as vomiting and diarrhea... both sometimes mixed with blood.
To filter, or NOT to filter... that was Lacie's question...
The first step in determining whether or not a water source requires filtration involves testing of the water for suspected contaminants. In Lacie's case, someone previously tested her water and determined that it (apparently) contained excess levels metals so a filter to remove or reduce metal concentrations in the water got installed.
To determine if Lacie should now remove her filter, she should first have the source water retested -- especially for metals. If after testing the levels detected do not exceed USEPA limits as defined in their Primary & Secondary Drinking Water Standards, and no other contaminant levels exceed acceptable levels, then perhaps she can remove the filter.
Do keep in mind, however, that well water quality changes all the time and water that contains metals or other contaminants one day may or may not contain them a week later. Studies have shown this especially true in areas where the water table level rises and falls on a regular basis.
And in conclusion...
Health departments, the EPA and drinking/well water professionals all around the world pretty much agree that water quality seldom remains static and that private well owners ought to test their well water at LEAST once a year for common water contaminants such as nitrates/nitrites and coliform bacteria. If a water source has had trouble with other contaminants -- like metals, for example -- in the past, then obviously the water should get tested for those contaminants, as well, at least once a year.
The key to making well water safe for human consumption lies not just in the filter used, but also in the testing that guides us through the filter selection process. In other words, Lacie, do not remove the filter until you have tested the water to make certain you no longer need it.
Total Copper in Water Test
Chromium in Water Test
Mercury in Water Test