All-clear given after Ohio toxic chemical leak; employee error blamed

Authorities have given the all-clear for residents in Toledo, Ohio, to return to their homes on Oct. 23 after a toxic chemical began leaking from a tank, forcing evacuations amid an explosion risk that has now passed.

The tank began leaking glycidyl methacrylate into the air the night of Oct. 20 at the MC Tank Transport company in north Toledo. Hundreds of residents were ordered to evacuate or shelter in place.

The afternoon of Oct. 23, Toledo Mayor Wade Kapszukiewicz announced that all residents could now return to their homes, after the evacuation order was reduced to a quarter-mile radius from the site the day before.

"As of late last night, the final contents of the tank vented out and so now the tank is entirely empty," Kapszukiewicz said at a news conference. "It did take longer than we thought it would, longer than we wanted it to, frankly."

As long as there was still chemical in the tank, there was a risk of an explosion that prevented hazardous materials first responders from approaching it, officials previously said.

"At this time, we do feel confident that the site is safe," said Toledo Fire and Rescue Battalion Chief Blake Molnar.

What caused the Ohio chemical leak?

Kapszukiewicz said Oct. 23 that the cause of the chemical release was an error made by an MC Tank Transport employee who was attempting to transfer the substance. The company has "accepted responsibility for what happened," he said.

"The event was caused when an employee of the company introduced a temperature level to the tank in the process of trying to transfer the liquid... it was the introduction of that temperature that caused it to happen," Kapszukiewicz said.

It was an employee who first called 911 and alerted authorities to the leak, officials said.

Officials originally said a risk of explosion was expected for a 12-hour window after the leak, but later extended that timeline and said the risk was present as long as the material was still in the tank. No explosion or fire occurred at any point, they said Oct. 23, though Kapszukiewicz previously called the release an explosion.

As the temperature and pressure inside the chemical tank decreased, the evacuation order was gradually reduced and the shelter-in-place order lifted in previous days.

"There's a lot of unanswered questions. There will of course be an investigation," said Environmental Protection Agency Region 5 Administrator Anne Vogel.

Dozens treated for symptoms after exposure to chemical

A total of 57 people sought treatment at hospitals for symptoms related to potential exposure to the chemical, Kapszukiewicz said. They are all now in "good condition," he said. Their symptoms included headaches, difficulty breathing and watery eyes.

"Certainly very serious things but happily nothing that began to approach a threat to life," he said.

The glycidyl methacrylate, an industrial chemical used to make certain plastics, paints and coatings perform better, is stored as a liquid but was leaking into the environment and air as a gas, authorities said. It formed a plume of material in the area, which combined with a heavy layer of fog to create a startling visual for residents who also reported smelling and tasting the chemical in the air.

Officials said people may experience irritation to their eyes, headaches or difficulty breathing, but the smell wasn't a sign that they were being exposed to levels that posed a long-term danger to their health, describing the chemical as mostly an "irritant."

Residents returning home should ventilate their homes by letting in fresh air, clean surfaces and throw out any uncovered foods, city health officials said.