AVONDALE, Ariz. -- The EPA released the results of mercury screenings at Agua Fria High School on Friday.

It says the homes of 66 students and staff were screened after their belongings were “found to be contaminated with mercury at levels of concern.”

Nine homes were contaminated with mercury.

Six had moderate levels of contamination. Three homes required “extensive remediation.” As a result, two families had to leave their homes for a few days. The EPA says those families are back at home.

All of the homes have been decontaminated.

The EPA says its emergency response efforts to the Feb. 12 mercury spill at the Avondale high school are complete.

EPA workers screened student and staff’s belongings and monitored the decontamination of Agua Fria High School for 11 days.

It has three years to investigate the cause of the mercury spill and to recover the cost of the cleanup.

The EPA has not released how much it cost to clean up the spill that contaminated classrooms, a boys’ locker room and two buses.

“It’s not something that you can just clean up with Lysol. You need to have very special equipment, and you need to make sure you get all of it out of the environment so that people aren’t continually exposed to mercury,” Dr. Rebecca Sunenshine said.

She is an epidemiologist for the Arizona Department of Health Services.

“When it’s in the environment, it vaporizes into the air and people can inhale it and that can cause problems. If you’re exposed to it for a long period of time, then it can have neurological effects that can be lasting and can cause a lot of problems,” she said.

Sunenshine added, “If a child played with mercury for a short time and didn’t really inhale it directly, they’re probably going to be fine. If that mercury gets on clothing and gets at home into the house and stays there for a long time and people are inhaling over a period of time, that’s when you can get those longer term effects.

Sunenshine said those effects include brain damage. Exposure to mercury can also damage your heart, lungs, kidneys and immune system.

Short-term effects of mercury exposure include shortness of breath, cough, sore throat, and eye irritation.

Friday, some Agua Fria students were relieve the cleanup is complete.

“I feel like it’s off my chest now. I don’t have to worry about people touching me and having the mercury on them,” sophomore Tiffany Thomas said.

The students say the Feb. 12 spill has disrupted their ability to learn in class.

“I can’t go to my original chemistry class because they stripped it all out and did what they had to do,” junior Chris Ruelas said.

“We have to go to a different class and we can’t do labs or anything,” he said.

“It’s affecting my chemistry class and the work that I’m doing in there ... I think it’s going to affect my finals.”

Five students admitted playing with the toxic metal in school.

Sources say two science teachers have been moved to other schools as a result of the spill.

Several students say there are now substitutes for those two teachers.

Agua Fria Unified School district officials have refused to say how the spill happened or where the students obtained the mercury.

Arizona Department of Health Services officials say there is not supposed to be any mercury in schools.

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