Some teachers and students from the École des decouvreurs in LaSalle are still suffering the effects of last week's carbon monoxide intoxication.
"About a dozen teachers have had to stay home. They've been reporting that they still have headaches, nausea, dizziness, memory lapses," said Mélanie Hubert, president of the teachers' union in an interview with CJAD 800.
Some children have also reported the same thing according to their parents on social media.
In all, 43 students and staff were hospitalized following the incident.
Dr. David Kaiser of Montreal's public health department said these are so-called residual symptoms that can persist.
"Unfortunately it's not unexpected," Kaiser told CJAD 800.
But it doesn't necessarily end there.
"We know that in the three to six weeks in general after exposure to carbon monoxide, people can have new symptoms that show up," said Kaiser.
"Things like memory, attention, mood, feeling lack of interest or symptoms that appear like depression."
Kaiser said that some people can also see symptoms that can last for months after that.
Hubert said the board has been scrambling to replace the teachers in this time of labour shortages.
CJAD 800 is still awaiting comment from the Marguerite-Bourgeoys School Board.