An Overland Park woman was forced out of her apartment after as much of 10 pounds of mercury spilled from an antique clock.

Fire department spokesman Jason Rhodes says the liquid apparently spilled weeks ago on a back porch of the woman’s apartment but she wasn’t aware it was dangerous mercury until a relative saw the spill Monday.

Overland Park Fire Department spokesman Jason Rhodes says in a news release that the mercury spilled out of tubes that were counterweights for an old grandfather’s clock.

The Environmental Protection Agency is advising on cleanup. The woman’s apartment was sealed until it is cleaned. Occupants of three other units were allowed to stay but advised to check with the Centers for Disease Control to see if they have exposure issues.