Manganese

Overview

CAS No.7439-96-5 (metal)
CAS No. 108-38-3 (cyclopentadienyl tricarbonyl)
CAS No. 106-42-3 (tetroxide)

Manganese (Mn) is a hard, gray metal that is frequently used in the production of steel. Workers may be harmed from exposure to manganese through the breathing of manganese fumes or dusts. Continued exposure can damage the lungs, liver, and kidneys. Exposure to manganese dust or fumes can also lead to a neurological condition called manganism. Manganism’s symptoms, similar to those of Parkinson’s disease, may include the following: trembling, stiffness, slow motor movement and potentially severe depression, anxiety and hostility. The level of exposure depends upon the dose, duration, and work being done.

Workers most at risk of being exposed to manganese often perform welding tasks. Welding occurs in the construction, manufacturing, transportation, mining, and agriculture industries and other occupations, such as pipe-fitters or millwrights. Somewhat smaller numbers of workers in the metallurgical and other manufacturing industries are also at risk.

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries.  If you work in an industry that uses manganese, please read chemical labels and the accompanying Safety Data Sheet for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.

The following resources provide information about occupational exposure to manganese. Useful search terms for manganese include “colloidal manganese,” “manganese-55,” and “manganese metal.”

NIOSH Chemical Resources

Related NIOSH Resources

• NIOSH Pocket Guide main search results:
  • Manganese compounds and fume (as Mn) (CAS No. 7439-96-5)
  • Manganese cyclopentadienyl tricarbonyl (CAS No. 108-38-3)
  • Manganese tetroxide (as Mn) (CAS No. 106-42-3)
• NIOSHTIC-2 search results for manganese —NIOSHTIC-2 is a searchable database of worker safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.
• NIOSH Immediately Dangerous to Life or Health Concentrations (IDLH) of Manganese—NIOSH reviews scientific data and researches methods for developing IDLH values.
• NIOSH Safety and Health Topic—Welding and Manganese: Potential Neurologic Effects —This NIOSH safety and health topic page provides links to resources to help workers and employers identify and control

Selected Publications

• NIOSH Criteria for a Recommended Standard: Welding, Brazing, and Thermal Cutting—DHHS (NIOSH) Publication Number 88-110

Related Resources

• Agency for Toxic Substances Disease Registry (ASTDR)—ToxFAQs: Manganese
• ASTDR—Toxicological Profile for Manganese
• Environmental Protection Agency (EPA) Chemistry Dashboard: Manganeseexternal icon
• EPA—Environmental Manganese: Guideline Exposure Levels, Evidence of Health Effects and Research Needsexternal icon
• EPA—Health Effects Notebook for Hazardous Air Pollutantsexternal icon
• EPA—Manganese, CASRN 7439-96-5, Integrated Risk Information System (IRIS) Summaryexternal icon
• National Library of Medicine (NLM)—Hazardous Substance Data Bank: Manganeseexternal icon
• NLM—Haz-Map: Manganeseexternal icon
• Occupational Safety and Health Agency (OSHA)—Hazard Communicationexternal icon
• OSHA—Safety and Health Topics: Manganese Fumeexternal icon
• OSHA—Safety and Health Topics: Manganese Compoundsexternal icon
• OSHA—Chemical Sampling: Manganese Cyclopentadienyl Tricarbonylexternal icon
• OSHA—Occupational Guideline for Manganesepdf icon
• United States Geological Survey: Manganesepdf iconexternal icon
• New Jersey Hazardous Substance Fact Sheets: Manganesepdf iconexternal icon

International Resources

• Canadian Centre for Occupational Health and Safety (CCOHS) Welding – Fumes and Gasesexternal icon
• OECD—eCHEM Portal search results for manganeseexternal icon
• European Chemicals Agency (ECHA) search results for manganeseexternal icon
• International Labour Organization (ILO)—International Safety Cards: Manganeseexternal icon
• International Programme on Chemical Safety (IPCS)—INCHEM search results for manganeseexternal icon
• Institute for Occupational Safety and Health of the German Social Accident Insurance—Gestis Substance Database search results for manganeseexternal icon