All tap water contains some impurities, but not all impurities make the water unsafe.
Some minerals pose no threat at a low level, while a higher concentration of the same mineral may be unhealthy—and some contaminants are unsafe at even extremely low levels.
If your tap water has an unpleasant smell or taste or is discolored, you should stop drinking it and get it tested as soon as possible. Even if your water looks and tastes fine, it’s a good idea to test it once a year. The Environmental Protection Agency (EPA) also recommends testing your water if anyone in the house is pregnant or experiencing recurring stomach ailments or if the house was built before 1986 and might still have some lead pipes. A full list of EPA recommendations for when to test your water is listed here: https://www.epa.gov/ground-water-and-drinking-water/home-drinking-water-test
The most commonly available home water testing kits use paper strips or powder, but these DIY methods are somewhat limited. Home tests are usually less sensitive than a lab test, and they may not be able to detect all types of contaminants. The paper strips, for instance, can be useful for a general overview of what’s in your water, but they don’t necessarily provide enough detail to tell you how to fix it.
For a more detailed and accurate analysis of what’s in your tap water, you can collect a water sample and have it tested by a lab. The EPA recommends using a certified lab so that you’ll be confident in the test results.
There’s an EPA lab in every state, and you can find one by searching the epa.gov site for: “Certified Laboratories for Drinking Water.” Once you have your results, you can make a plan to treat your water. Note that the EPA maintains safety standards for all tap water except well water—if you have a well or another private water source, you’re responsible for the safety of that water. It might be even more important to test regularly if you have a private well.
