An alarm at the Lappeenranta industrial bakery facility in southeastern Finland sounded at around 11:30 p.m. Sunday night.
Rescue teams were able to get the leak under control after shutting down the factory and airing out the facility for a few hours.
Ten people from the facility were transported to the South Karelia Central Hospital in Lappeenranta with breathing difficulties.
Police officials are currently investigating the cause of the leak.