CAS No. 7440-48-4

Cobalt (Co) is a hard, gray metal that occurs naturally. It is found in rocks, soil, water, plants, and animals, including people. It can harm the eyes, skin, heart, and lungs. Exposure to cobalt may cause cancer. Workers may be harmed from exposure to cobalt and cobalt-containing products. The level of harm depends upon the dose, duration, and work being done.

Cobalt is used in many industries. It’s used in cutting and grinding tools, pigments and paints, colored glass, surgical implants, batteries, and some electroplating. Its radioactive isotope is used in imaging and food irradiation. Some examples of workers at risk of being exposed to cobalt include the following:

  • Workers who work in industries processing cobalt-alloys
  • Miners who work in the metal mining industries
  • Workers involved in the production or use of cutting or grinding tools
  • Employees who work at nuclear or irradiation facilities

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses cobalt, please read chemical labels and the accompanying Safety Data Sheets 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 cobalt. Useful search terms for cobalt include “cobalt metal dust,” “cobalt metal powder,” “cobalt metal fume,” and “elemental cobalt.”

NIOSH Chemical Resources

Logo of NIOSH Pocket Guide

The NIOSH Pocket Guide to Chemical Hazards (NPG) helps workers, employers, and occupational health professionals recognize and control workplace chemical hazards.

Logo of Manual of Analytical Methods.

The NIOSH Manual of Analytical Methods (NMAM) is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed.

Logo of Health Hazard Evaluations consisting of three letters: HHE

The Health Hazard Evaluation Program (HHE) conducts onsite investigations of possible worker exposure to chemicals. Search the HHE database for more information on cobalt.

Related NIOSH Resources

Selected Publications

Related Resources

International Resources

Page last reviewed: November 2, 2018