Fire officials are investigating a mercury spill at an office building in downtown D.C.

The spill happened about noon Tuesday at a building in the 1300 block of I Street NW, Assistant Chief Brian Lee said.

Lee, who was on his way to the site of the incident, did not know what caused the spill or the type of business being conducted in the affected office.

He said “a few ounces” of mercury were spilled.

No injuries have been reported, but emergency crews are checking employees for possible exposure. Mercury exposure can affect the brain, heart, kidneys and other vital organs.

Mercury can be found in products such as thermometers and some light bulbs and is commonly found in homes, dentists’ offices and schools.