An acid spill at an auto plant sent 23 people to a Niagara Region hospital Tuesday, including three who were directly exposed to the hazardous material, but all were discharged later in the day.
The spill took place at THK Rhythm Automotive plant in St. Catharines, Ont. First responders said they were called in the morning after contractors were exposed to a vapour cloud of hydrochloric acid that was released after a concentrated leak
"Staff on scene accidentally bumped a valve, which released approximately five litres of hydrochloric acid," Dave Upper, fire chief of St. Catharines Fire Services, said in a phone interview.
"Once they realized that the valve was open and the spill occurred, they immediately closed the valve."
Three people were directly exposed through inhalation and skin contact, said Upper. The liquid transformed into a vapour cloud and 20 other staff members in the area were exposed solely through skin contact with the vapour, he said.
Emergency responders used decontamination showers on site to wash those who were exposed before taking them to hospital, Upper said, adding that the hazardous material was contained within the plant and there was no risk to public health.
The three people who were directly exposed were taken to hospital in stable condition via ambulance, while the 20 others were taken by a city bus arranged by fire services.
"We wanted to get them there quickly so they could get checked and monitored, and we did not want to tie up all of the Niagara EMS units," Upper said.
EMS Operations Supt. Bryce Brunarski said nine people taken to hospital had minor exposure to the vapour cloud and another 10 individuals were asymptomatic, with minimal exposure to the leak, but taken to hospital as a precaution.
"We don't know exactly how long they were exposed or how much of the irritant they would have inhaled or had exposed to their skin," he said.
Brunarski said Niagara Region EMS was in touch with the Canadian Transport Emergency Centre, which recommended that exposed individuals be monitored for 48 hours.
The Niagara Health hospital network said it treated 23 people at its St. Catharines site starting at 10:41 a.m. as a result of the acid spill. It had previously asked residents to avoid the emergency department unless absolutely necessary as it dealt with the influx of patients, but said normal operations resumed as of 1:30 p.m.
Dan Dakin, manager of communications for Niagara Health, confirmed that all 23 patients were assessed and discharged.
The auto plant said it did not have any immediate comment.