WASHINGTON -- A student brought a small bottle that contained mercury onto a school bus and into Francis Scott Key Middle School in Silver Spring Wednesday morning.
Initially, Montgomery County Fire and Rescue said it didn't appear that anyone was exposed to the vial, but The Washington Post reports fire officials later detected a spill on the bus.
A Montgomery County Public Schools spokesman tells WTOP the bottle was opened at some point.
The bus dropped kids at Francis Scott Key Middle School and Charles Drew Elementary School. Both are in the Silver Spring area.
Fire spokesman Pete Piringer says a total of 35 children were being evaluated at the two schools.
Exposure to high levels of mercury can harm the brain, heart, kidneys, lungs, and immune system of people of all ages, the EPA says.
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