Five people were taken to hospital with respiratory issues following some sort of chemical spill at a recycling plant in North York early Friday morning.

It happened at around midnight at Canada Fibers Ltd. on Arrow Road near Sheppard Avenue and Highway 400.

Toronto Fire Services says that workers were separating some blue box materials when they came into contact with an unknown substance, which produced a “minor irritant.”

Workers that spoke with CP24 reported a range of symptoms as a result, including sneezing, coughing and some headaches.

“We had several civilians with respiratory difficulties so in turn we isolated the situation and had decontamination crews on site,” Platoon Chief Doug Harper told CP24 at the scene.

About 50 workers were at the facility at the time of the call and all of them were given access to temporary showers set up in a parking lot to decontaminate.

Harper said that crews have been unable to determine what the chemical was but believe that it was something that may have been improperly disposed in a blue bin.

“It is a recycling plant where they separate everything we put in our blue bin. We are supposed to separate properly but unfortunately some people don’t and it exposes these workers to chemicals that people sometimes throw out improperly,” he said.

Toronto Fire Services has ventilated and searched the building but is planning to continue their investigation at the scene this morning.