Scientific opinion on the tolerable upper intake level for manganese

Area of Science:

• Nutritional Science
• Toxicology
• Food Safety

Background:

• The European Commission (EC) requested a scientific opinion on the tolerable upper intake level (UL) for manganese.
• Manganese intake and its potential adverse health effects, specifically neurotoxicity, were assessed.

Purpose of the Study:

• To determine the tolerable upper intake level (UL) for manganese.
• To evaluate the risk of manganese-induced neurotoxicity from dietary intake.

Main Methods:

• Systematic literature reviews of human and animal studies were conducted.
• Dose-response relationships for manganese-induced neurotoxicity were investigated.
• Estimated background dietary intakes of high consumers were used in the absence of sufficient data for UL determination.

Main Results:

• Neurotoxicity is supported as a critical effect of excess manganese intake in available studies.
• Data were insufficient to characterize a dose-response relationship or establish a reference point for manganese-induced neurotoxicity.
• A safe intake level was established: 8 mg/day for adults (≥18 years, including pregnant and lactating women) and 2–7 mg/day for other groups.

Conclusions:

• A definitive UL for manganese could not be established due to data limitations.
• A safe intake level, based on high background dietary intakes, provides an indication of intake without expected adverse effects.
• The established safe intake level has limitations as it does not define the threshold for adverse effects.