Common impurities found in tap water

Here's a quick rundown of some common impurities that may be found in residential water supplies and what you can do to reduce them from drinking water.* Water quality varies by municipality and while this page identifies some common impurities, this list is not comprehensive. For more information on what's in your drinking water, we recommend visiting the U.S. Environmental Protection Agency (EPA) where you can also find information on your local annual water quality report (Consumer Confidence Report) and conducting a water test in your home.

Heavy Metals

Learn how consuming high levels of heavy metals can cause a wide range of short-term and long-term health conditions.¹ And be sure to visit our informative Lead Article to see how lead can contaminate residential water, and what you can do to reduce it.

Lead: Unhealthy levels of lead have been detected in some U.S. water supplies, and exposure has been linked to nervous system damage and other health issues.¹
Copper: While copper poses the most danger to young children, excessive exposure can cause gastrointestinal distress, liver issues and kidney damage in adults.¹
Mercury: The organic form of mercury can lead to adverse effects in children, and at high concentrations, long-term exposure can lead to kidney damage in adults.¹

Taste, Odor, and Appearance

Some impurities can result in cloudy, bad-smelling or off-tasting water. While not necessarily dangerous to your health², unpleasant drinking water can discourage good hydration habits.

Chlorine: Low levels of chlorine may be added to public water supplies to inactivate bacteria and viruses. Unfortunately, it can affect the taste and smell of your drinking water.
Particulates: Debris that can end up in your tap includes rust, dirt, sand and sediment that can give your water a cloudy appearance, along with an unpleasant odor and taste.
Zinc: While zinc is an essential trace element, high levels of this metal can add an unpleasant taste and odor to your drinking water.

Pharmaceuticals and Other Contaminants

There are a variety of other impurities that can sometimes be found in tap water, including trace levels of pharmaceuticals and industrial chemicals.³

Pharmaceuticals: Trace levels of pharmaceuticals such as Ibuprofen and Naproxen have been reported in the water cycle, including groundwater and, to a lesser extent, drinking water.
Industrial Contaminants: While cases are uncommon, industrial chemicals have been known to make their way into residential drinking water supplies.
Pesticides and Other Chemicals: Herbicides, pesticides and other organic chemicals can contaminate drinking water supplies. Although cases are uncommon, high levels over time can be dangerous.