A new water heater is being installed at the Atikokan pool after that was determined to be the cause of a carbon monoxide leak that sent 18 people to hospital last Tuesday night.
Five of the victims had to be airlifted to Minneapolis for treatment in a hyperbaric chamber.
Everyone was released from hospital by the following day.
Bill Limerick, environmental health team leader with the Northwestern Health Unit, assured the pool wouldn’t re-open until tests showed it free was of the noxious fumes.
He said tests taken Friday found carbon monoxide was 900 parts per million (ppm) at the source—a water heater installed in 1976—which is enough to cause headaches, dizziness, and fatigue in a 15-minute period.
In a closed area, that amount could be fatal after two hours.
The health unit said those people who were in the pool that evening should be fine. Dr. Pete Sarsfield, chief medical officer of health, said anyone breathing in a fairly high level of carbon monoxide fumes over a short period of time would be fine once the CO was out of their system.
But it may be a different story for those exposed to low doses over a long period—such as staff at the pool—depending on how long the fumes have been leaking out.
Dr. Sarsfield said if anyone breathed in low doses of the fumes over a prolonged period, they could experience symptoms that imitate chronic fatigue syndrome, as well as irritability and mild personality changes.
Long-term studies are sparse and inconclusive as to whether that is reversible, he added.
“But ‘if’ is the key word. We don’t know how long it’s been leaking,” Dr. Sarsfield stressed, adding he also didn’t know what the level of carbon monoxide might have been in other areas of the pool.
Limerick said the Technical Standards and Safety Authority would be filing a full report with the municipality, which may indicate how long the tank had been leaking and how many ppm of CO were in other areas of the building.
The incident began just after 9 p.m. last Tuesday when 13 swimmers and two lifeguards became ill at the pool. The victims were taken to the hospital by ambulance, where all were treated with oxygen.
But five had to be airlifted to Minneapolis for treatment in a hyperbaric chamber, a pressurized chamber that rapidly discharges carbon monoxide from the body.
“The only chamber [in Ontario] that we know of is down in Toronto,” Atikokan hospital CEO Bruce Villella said, noting it was shorter distance to transport the people to the States.
Those visiting the pool that day were phoned, and five others showing symptoms were treated at the Atikokan hospital.
All treated at Atikokan were discharged by noon Wednesday while those sent to Minneapolis returned home by 5 p.m. that day. The municipality picked up all expenses for those airlifted out, including chartering a plane to bring them home.
As of Monday, no lawsuits had been filed against the municipality.
“Not that I’m aware of,” Mayor Dennis Brown said but admitted that was a possibility.
A toxic asphyxiant, carbon monoxide is an odourless, colourless gas caused by incomplete combustion. When people breathe in the fumes, it binds with hemoglobin so they don’t get oxygen into their system, Limerick said.