Six NSW ambulances, the fire brigade and a HAZMAT team were called to the Stanley Street school at 10.15am to respond to a "hazardous materials incident".
One student has been transported to Auburn Hospital in a stable condition “for assessment”, a NSW Ambulance spokesman told news.com.au.
The other students are reportedly suffering from dizziness and minor respiratory difficulties.
“We have up to seven children who are unwell,” a spokesman said.
“They are feeling light-headed and dizziness, but we don’t expect that it is serious.”
It is unclear what substance from the science block was exposed at the time but Fire and Rescue NSW said atmospheric testing detected carbon monoxide.
“HAZMAT did a test of the air and only found small traces,” says a NSW Police spokesperson.
A Fire and Rescue NSW spokesman also told the publication that their crew had contained the material in a fume cupboard by 11:46am.
The condition of the students is reportedly “non-life threatening”.
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