NORTHPORT, N.Y. (CBSNewYork) — CBS2 has been reporting on complaints about a foul odor at Northport Middle School for months.

On Sunday, the school district announced that a new environmental study found that smell could potentially be from a dangerous chemical. As a result, the school will be closed for the rest of the school year and will be relocating students elsewhere.

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CBS2’s Christina Fan found out what’s next for the school’s more than 600 students.

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Parents say the school has been the source of repeated illnesses among students over the years, including migraines and nausea. Their suspicions seem to be confirmed by a letter the superintendent sent out over the weekend. It states that soil samples from two septic systems contained elevated levels of benzene that will require further remediation.

MORE: Read The Letter

Benzene is a potentially dangerous chemical compound that, according to the Centers for Disease Control, can cause headaches, confusion, and even cancer if exposed at high levels over a long period of time.

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Parents have been complaining about an overpowering stench in classrooms. One mother, whose three sons went to the school, said it was about time the district took action.

“I think I felt every possible emotion, like relief but not relief,” parent Denise Schwartz said. “There is also the worry where I didn’t want to be right. I was hoping his test came back clean so I wouldn’t have to worry the rest of my life and my children’s lives whether one of them might have gotten more serious exposure than I thought and could, God forbid, end up with a disease.”

Bill Blaney said his daughter, who is in the sixth grade, also experiencing symptoms.

“I asked how many days have you had these headaches and stomachaches since you started in September, and she said every day,” Blaney said.

So far, preliminary air testing indicated no observable detection of benzene in the building.

“One more day of any kid in that school was one day too many,” Blaney said.

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Classes have been canceled for Tuesday and Wednesday. Officials hope to finalize a relocation plan by Thursday, Fan reported.