The Northport-East Northport Union Free School District has revealed the findings from preliminary soil testing done at its middle school after parents and students complained about an odor in the building.

The school district says an outside environmental firm detected elevated levels of mercury in the leaching pool, or cesspool, outside the building.

Mercury is a heavy metal, and health impacts could include damage to the thyroid and the kidney. It could also cause learning disorders, neurological disorders, tremors, memory loss and headaches.

The testing was preliminary, but as a precaution the school is relocating three classrooms for now.

Environmentalists are also doing mercury vapor air tests inside the classrooms, but those results are expected sometime this week.

As News 12 has reported, some teachers and students at Northport Middle School say something in the building has been making them sick for years. Parents even organized protests and a 'sick out' calling for action and even wanted the school to be closed.

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Recently, the school board voted to have environmentalists get to the bottom of the issue.

In response to the findings, the district says it is also relocating buses away from the middle school, and that the school will not be used as a fueling station for the district vehicles or buses.

District officials are also telling parents that if their child does have issues, bring them to a pediatrician and inform the school nurse and building principal.

The district has not announced plans to remove the mercury from the middle school site and will only say testing is ongoing.

A full report from the environmental testing firm is expected by this March or April.