SOUTH BRUNSWICK — A Central Jersey high school was evacuated after three students felt light-headed during a classroom discussion.

The students became sick in a classroom at South Brunswick High School, which was evacuated as a precaution, police said. Emergency personnel sent to the school and firefighters also took air measurements and determined the air was safe, according to police.

Interim school superintendent Dr. Gary P. McCartney said "to the best of our understanding, the topic made someone feel ill enough that they faint" and two other students "semi-fainted" when they became light-headed. Seven other students told their teacher they felt "queasy," according to McCartney, and the teacher called for assistance.

CBS New York reported the students felt ill during a classroom discussion about blood and HIV.

"The whole concept of blood effects kids differently," McCartney said, comparing it to some of the more graphic dialogue on ABC's "Grey's Anatomy" that turns some people from watching the show. "I don't know whether it's as simple as that or someone saw a slide or something touched them the wrong way in terms of making them sick."

McCartney said an EMT worker told him it's not uncommon for people to faint after seeing someone else do the same thing, in a domino effect.

McCartney, who returned to South Brunswick as superintendent after retiring in 2014, said he was glad no one was injured and nothing was identified in the air that would have been "a material that shouldn't have been."

Students returned to class by 11 a.m.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com.

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