LAS VEGAS, Sept. 9 (UPI) -- Walter Johnson Junior High School in Las Vegas was closed for a second day after hundreds of students were screened for possible mercury contamination.
Some 1,200 students and at least 100 staff members were screened for possible mercury contamination beginning Wednesday. They were kept at the school for about 17 hours Wednesday into early Thursday while being examined for exposure and contamination. Nine students and three staff members were quarantined, but were released by about 5 a.m. Thursday.
"The amount we're were dealing with was the equivalent of an old school thermometer," said Capt. Ken Young with Clark County School police.
A teacher discovered a student playing with the substance at about 11 a.m. Wednesday. Hazmat teams were called out and the students were systematically screened. While mercury, a neurotoxin, is found in the environment, high levels can lead to death.
The school said it will spend the coming days decontaminating the classroom buildings. It is unclear when students will be able to return to class.