Four contamination incidents have occurred since July at Outokumpu Oyj's Tornio steel facility in Finland, Reuters reported Oct. 16, citing the country's nuclear watchdog, STUK.

All four involved americium, a radioactive element that can be dangerous and potentially deadly if inhaled or swallowed, the regulator said, although noting that it could be hard to detect.

On Oct. 12, a batch of scrap metal at the plant was discovered to contain the element. The concentration strength was about 1 to 2 gigabecquerels, STUK said, noting that the events' recurrence qualifies as an International Nuclear Event Scale radiation incident.

The contaminated materials came from the Netherlands and the Baltic region but were likely to have originated outside Europe.

Outokumpu said production was not affected and products were not contaminated. Workers were also forced to wear oxygen masks but were not exposed to the material.

The company noted that it has addressed the issue with its suppliers, who were not identified.