Tannins and lignins in your drinking water are not typically a health concern, but they can cause unpleasant odors, tastes, and discoloration. This article will cover how they get into your drinking water, what levels may cause problems, and how to test for them.

 

Tannins and Lignins in Drinking Water at a Glance:

What Are Tannins and Lignins?

 

Tannins and lignins are organic compounds that naturally occur in vegetation. They often come from decaying plant matter such as leaves, wood, roots, pine needles, moss, peat, and more.

 

How Do Tannins and Lignins Get Into My Drinking Water?

 

As plant matter decays in water, it naturally releases tannins and lignins. This is similar to what happens when tea is steeped in water and releases its compounds. Tea actually contains both tannins and lignins. If you have ever steeped tea for too long, it can release high levels of tannins, which contribute to its bitter flavor.

 

Tannins and lignins are most commonly found in shallow wells, which are typically less than 100 feet deep. This is because shallow wells are more affected by surface water, which has a higher concentration of plant material. If a well draws water from a deep aquifer, it is less likely to contain these compounds.

 

What Level of Tannin and Lignin in Drinking Water Is Dangerous?

 

Tannins and lignins in drinking water typically do not pose a health risk. Instead, they can cause cosmetic and aesthetic problems with your water. They can cause water to turn brown, develop a bitter or earthy flavor, and have an unpleasant odor.

 

Cooking with water that contains high levels of tannins and lignins can also discolor some foods and impart unpleasant flavors.

 

Tannins and lignins can also stain clothing and faucets with a brown coloration.

 

These negative effects can typically begin around 1 ppm of tannins and lignins in your water but become more severe as the concentration increases.

 

How Do I Know if It’s Tannins or Iron in My Water?

 

The only way to know for sure whether your water is colored due to tannins or high iron levels is by having it tested at a certified laboratory.

 

There is also a simple method you can try for free at home. Leave a glass of discolored water sitting overnight. If the color settles to the bottom of the glass, it is more likely to be iron. If the color stays evenly distributed throughout the water, it is more likely to be tannins and lignins. However, other factors can affect the results, so this method is not 100% accurate.

 

Because iron and tannins require different filtration solutions, it is recommended that you test your water before trying to address the issue and potentially wasting money on the wrong treatment.

 

How To Test for Tannins and Lignins in Drinking Water

 

To test for tannins and lignins, we recommend using the Safe Home Premium In-Lab Test Kit. This test allows you to collect a water sample and have it analyzed at our EPA-certified lab. It will also test for other parameters that could be causing similar issues, such as iron, helping you identify the source of the discoloration, taste, and odor in your water.

 

What To Do if Your Tannin/Lignin Levels Are Too High

 

A common and highly effective method for reducing tannin and lignin levels is an anion exchange resin, sometimes referred to as a tannin softener. These systems are similar to traditional water softeners but use a different type of resin designed to capture tannins.

 

This can be a more expensive treatment solution because these resins can become far less effective when dealing with hard water. As a result, you may need a traditional water softener installed before the tannin treatment system.

 

There are also newer technologies, such as Zeta media, that can attract and remove a variety of contaminants from water, including tannins. While there are mixed reviews regarding the effectiveness of these systems, they may be worth discussing with a water treatment professional.

 

FAQ about Tannins and Legnins in Drinking Water

What Do Tannins and Lignins Look Like in Water?

Tannins and lignins can cause water to appear yellow, brown, or tea-colored. The exact color and intensity will depend on the concentration and other minerals or contaminants present in the water.

 

Are Tannins More Common in Well Water?

Yes. Tannins and lignins are more commonly found in shallow wells because they can be affected by surface water and decaying vegetation. Wells that draw from deeper aquifers may be less likely to contain significant levels of these compounds.

 

Are Tannins and Lignins in Drinking Water Dangerous?

Tannins and lignins in drinking water are generally considered aesthetic concerns rather than health concerns. They can cause brown or yellow discoloration, unpleasant odors, bitter or earthy tastes, and staining.