Twenty-two students and a teacher were inside the classroom at Hine Junior High School in Southeast Washington when the mercury spilled. All were checked and no one was hurt.

``We initially were going to confiscate that clothing, but it's far below the accepted level of mercury that we consider dangerous,'' said Alan Etter, spokesman for the District of Columbia Fire and EMS Dept. ``The amount of mercury involved here was pretty much negligible,'' Etter said, adding that no long-term health effects were expected.

The school was never evacuated.

Monday's incident came two months after a more serious mercury spill at Ballou High School, also in Southeast Washington. That school was closed more than a month after a student allegedly took mercury from an unlocked chemistry lab and spilled it around the building.

Unsafe levels of mercury were also later found in several homes and on a Metrobus. About 1,000 Ballou students had to attend classes at other sites while the building was cleaned.