What Is Manganese?
The NIH Office of Dietary Supplements says manganese is an essential trace element that is naturally present in many foods and available as a dietary supplement, and lists a tolerable upper intake level of 11 mg a day for adults 19 and older.
The EPA lists a secondary drinking water standard for manganese of 0.05 mg/L, based on black to brown color, black staining and a bitter metallic taste, and an EPA drinking water health advisory sets a lifetime health advisory value of 0.3 mg/L to protect against concerns of potential neurological effects, along with a one-day and 10-day advisory of 1 mg/L for acute exposure. A USGS study reports that about 7 percent of domestic private wells in the United States have manganese at levels that may present a potential human health risk, and that these wells provide drinking water for an estimated 2.6 million people.
A 2012 review and meta-analysis in Neurology notes that high manganese exposure, as occurs in some miners and workers at manganese processing facilities, can lead to a form of parkinsonism called manganism.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Government sourceThe NIH Office of Dietary Supplements says manganese is an essential trace element naturally present in many foods and sold as a supplement. NIH Office of Dietary Supplements ↗
- Government sourceThe NIH Office of Dietary Supplements lists a tolerable upper intake level for manganese of 11 mg a day for adults 19 and older. NIH Office of Dietary Supplements ↗
- Regulatory filingThe EPA lists a secondary drinking water standard for manganese of 0.05 mg/L, based on color, staining and a bitter metallic taste. US EPA ↗
- Regulatory filingAn EPA health advisory sets a lifetime value of 0.3 mg/L for manganese in drinking water to protect against potential neurological effects. US EPA ↗
- Government sourceA USGS study reports about 7 percent of US private wells have manganese at levels that may pose a health risk, serving about 2.6 million people. US Geological Survey ↗
- StudyA 2012 review notes that high manganese exposure in some miners and processing workers can lead to a form of parkinsonism called manganism. Neurology, via PubMed Central ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.