The investigation has been closed into a mercury spill at Carson High School, officials said Monday.
"The Carson City Sheriff's Detective Division determined the spill was more of an unintentional act by a student playing with the blood pressure cuff," said Sgt. Bob White.
On Sept. 14, the screw cap was discovered missing from a vial of mercury contained in a gauge in an outdated blood pressure machine in the nurse's office
The breach leaked about 6 milliliters of the toxic element onto some papers on a desk.
The nurse noticed the spill about 11 a.m., 90 minutes before the school's 2,526 students were set to leave classes early to accommodate teacher staff meetings.
The spilled prompted the evacuation of the school and decontamination of 18 students and eight staff members. School reopened two days later after $15,000 was spent to decontaminate the building on Saliman Road.
"The Carson City Sheriff's (Department) conducted an investigation into the possibility of an intentional release of mercury," White said. "Initially there were approximately 18 individuals who would have had access to the blood pressure cuff. The investigation reduced the number from 18 to three students who had the opportunity to cause a spill."
White said since no fingerprints could be lifted from the equipment and no one interviewed could offer any information on who was responsible, the case was closed unless further information comes to light.
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