Manganese (Mn), necessary for healthy bone structure, is a component of several enzyme systems, including manganese-specific glycosyltransferases and phosphoenolpyruvate carboxykinase. Median intake is between 1.6 and 2.3 mg/day; absorption is 5 to 10%.
Manganese toxicity is more often a risk with people who mine and refine ore, but even low-level occupational exposure and contaminated foods (eg, infant formula) or water may be harmful. Prolonged exposure causes neurologic symptoms resembling those of parkinsonism or Wilson disease and may also alter cardiovascular function. Treatment, which may not relieve the neurologic symptoms, includes eliminating exposure and chelation.
(See also Overview of Mineral Deficiency and Toxicity.)