A GoodLife Fitness club has been evacuated after noxious fumes sent six people to hospital including one with potentially life-threatening injuries.

The gym at 185 The West Mall, south of Dundas Street West, was evacuated around 3 p.m. on Saturday. The chief complaints were shortness of breath after gym users inhaled some sort of fumes.

The injuries of the other five now in hospital are said to range from not serious to serious.

Twenty-five others were treated by paramedics and released at the scene.

“I think it was an incorrect mixture of pool chemicals,” Toronto EMS’s Peter Rotolo said. “The fire department deemed it safe and everybody has returned and the problem was corrected fairly quickly. The building has been ventilated and the air quality is good.”

One woman posted on Twitter that her mother, who was at the gym, was okay but that she was “not completely impressed” with how the employees handled the situation.