Workers at the East Boulder mine near Big Timber were kept from going underground after sensors carried by employees showed elevated levels of mercury, a company official said Friday.
Five employees wearing mercury patch testers came back with the elevated mercury levels, according to Heather McDowell, a spokesperson for the mine, which is owned by Sibanye Stillwater.
Mine officials are trying to determine whether the mercury came from an underground rock source, or whether the test were faulty, McDowell said. Sibanye Stillwater recently switched to a new equipment provider.
Mercury is a naturally occurring element that can be toxic to people with exposure in even small levels, according to the World Health Organization. Risks include damage to nervous, digestive and immune systems, and on lungs, kidneys, skin and eyes.
The East Boulder mine is one of two Montana mines owned by South Africa-based Sibanye Stillwater, which is North America's largest producer of platinum and palladium. The other is the Stillwater mine in Nye.
