Manganese

Manganese is a trace mineral that is present in tiny amounts in the body. It is found mostly in bones, the liver, kidneys, and pancreas. Manganese helps the body form connective tissue, bones, blood clotting factors, and sex hormones.

Manganese is a naturally occurring element found in food, rocks and soil. It is usually present in Minnesota ground and surface water. Your body needs some manganese to stay healthy, but too much can be harmful. The recommended manganese intake for people over eight years old varies from 1,900-2,600 micrograms (µg) per day. Infants (under one year old) should consume 600 µg or less of manganese per day. Learn more on the health effects at MDH's webpage.

The EPA has established two sets of drinking water regulations - National Primary Drinking Water Regulation (NPDWRs) & National Secondary Drinking Water Regulations (NSDWRs). Manganese is a secondary contaminant. 

NPDWRs are a set mandatory quality standard. These enforceable standards are called maximum contaminant levels (MCLs). The MCLs are established to protect the public against consumption of drinking water that presents a risk to human health.

NSDWRs are not mandatory to meet water quality standards. It regulates 15 natural compounds that commonly exist in drinking water. These standards are not enforced as they are a guideline to assist in managing drinking water aesthetic considerations, such as taste, color, and odor. These contaminants are not considered a risk to human health at the secondary maximum contaminant level (SMCL). 

Recent scientific studies of manganese exposure have prompted the MDH to create new guidance values for water consumption. Due to the possibility that water may exceed MDH safe consumption guidelines, MDH recommends considering home water treatment or bottled water for drinking, cooking and preparing infant formula if you choose to consume City municipal water.

Here are MDH's recommended health guidelines:

•  If you have an infant less than one year old who drinks tap water or formula made with tap water, a safe level of manganese in your water is 100 parts per billion (ppb) or less.

• If you have an infant less than one year old who never drinks tap water or formula made with tap water, a safe level of manganese in your water is 300 ppb or less.
• If everyone is more than one year old, a safe level of manganese in your water is 300 ppb or less.

For an overview of how manganese effects you and your family, view MDH's quick fact sheet. 

Please note that manganese can also be present in private well systems and residents are encouraged to have their wells tested annually. Learn more by reading the MDH Owner’s Guide to Wells and for a list of accredited labs, go here.

There are several things you can do to filter manganese out of your drinking water. Certain types of home water treatment devices remove or reduce manganese (some refrigerator water filters, pour-through pitchers, units that attach to faucet, water softeners, etc.).

If you already have a home water treatment device that removes or reduces manganese, you may want to test the water levels coming from the tap you use for drinking and cooking. This will give you a general idea of the manganese level in you water. If you choose to test your water, we recommend using one of the accredited labs listed on MDH’s webpage.

If you do not have a home water treatment device that removes or reduces manganese, you may want to consider installing one on the tap used for drinking, cooking and preparing infant formula. Bottled water is a short-term alternative. Look for bottled water that is NOT labeled “mineral water".

Treatment devices should be certified to remove manganese. All home water treatment units require maintenance. Visit the MDH webpage on Home Water Treatment to learn more.

Homeowners with private wells are responsible for having their wells tested. Learn more by reading the MDH Owner’s Guide to Wells.