What We Know About the Train Derailment in Ohio

In early February, a train carrying toxic chemicals derailed in eastern Ohio, igniting a fire that swept the town of East Palestine in smoke. Fearful of a major explosion, the authorities carved out an evacuation zone and then carried out a controlled release of toxic fumes to neutralize burning cargo inside some of the cars.

Residents feared for their health as concerns have mounted about the effect of the derailment and the fire on the environment and the transportation network.

Here’s what we know.

What happened?

Around 9 p.m. on Feb. 3, a train derailed in East Palestine, Ohio, a village of about 4,700 residents about 50 miles northwest of Pittsburgh. About 50 of the train’s 150 cars ran off the tracks on its route from Madison, Ill., to Conway, Pa.

The train, operated by Norfolk Southern, had been carrying chemicals and combustible materials, with vinyl chloride, a toxic flammable gas, being of most concern to investigators. A huge fire erupted from the derailment, sending thick billowing smoke into the sky and over the town. Residents on both sides of the Ohio-Pennsylvania border were ordered to evacuate, as Gov. Mike DeWine of Ohio raised alarms about a possible explosion.

Local and federal officials started an investigation that involved the National Transportation Safety Board and the Environmental Protection Agency.

Has there been harm to the environment?

The derailment has sparked concerns about air, soil and water pollution.

On Feb. 10, the E.P.A. said that about 20 rail cars were reported to have been carrying hazardous materials. Chemicals including vinyl chloride, butyl acrylate, ethylhexyl acrylate and ethylene glycol monobutyl ether were “known to have been and continue to be” released to the air, surface soil and surface waters, the E.P.A. said.

On Feb. 12, the E.P.A., after monitoring the air, said it had not detected contaminants at “levels of concern” in and around East Palestine, although residents may still smell odors. Working with Norfolk Southern and the Columbiana County Emergency Management Agency, the E.P.A. also screened the air inside about 210 homes and said it had not detected vinyl chloride or hydrogen chloride, which can cause life-threatening respiratory issues.

An additional 200 homes were still awaiting screening, the agency said.

Fearing an explosion, the authorities held a controlled release of the toxic materials from five train car tankers on Feb. 6, and the contents were diverted to a trench and burned off.

Precautionary measures were taken in the wider region. The West Virginia subsidiary of American Water, which provides water services in 24 states, said on Feb. 12 that it had not detected any changes in the water at its Ohio River intake site. But it installed a secondary intake on the Guyandotte River in case an alternate source was needed. The subsidiary, which serves more than half a million people, said it also enhanced its treatment processes.

Residents were evacuated and face uncertainty.

Just after the derailment, about 1,500 to 2,000 residents in East Palestine were told to evacuate the area. Schools were closed for the week, along with some roads. Norfolk Southern said it had donated $25,000 to help the American Red Cross set up shelters and deal with the influx of people.

On Feb. 6, Mr. DeWine extended the evacuation order to include anyone in a one-by-two-mile area surrounding East Palestine, including parts of Ohio and Pennsylvania.

One of the evacuees, Ben Ratner, told CNN that he and members of his family had been extras in a 2022 movie adaptation of the 1985 Don DeLillo novel “White Noise.” In that story, a train derails and spills chemicals, causing an “airborne toxic event” that forces the evacuation of a small, Midwestern college town.

On Feb. 8, the governor’s office said residents were permitted to return home, after air quality samples measured contaminants below levels of concern. The East Palestine Water Treatment Plant said it had not seen adverse effects. Norfolk Southern said in a statement that its own experts and contractors were testing water from private wells, although those homeowners were encouraged to use bottled water.

Norfolk Southern offered residents who did not want to return home assistance with hotel expenses.

There have been no reports of injuries or deaths from the derailment, but many are questioning how safe the area is. On social media and in news reports, some residents said that fish and frogs were dying in local streams. Some shared images of dead animals or said they smelled chemical odors around town. The arrest of a reporter during a news conference about the derailment led to online criticism of the law enforcement response.

Residents have complained about headaches and feeling sick since the derailment. A federal lawsuit filed by two Pennsylvania residents is seeking to force Norfolk Southern to set up health monitoring for residents in both states, The Associated Press reported, and to pay for related care for those in a 30-mile radius.

How long will it take to get back to normal?

The E.P.A. informed Norfolk Southern on Feb. 10 that it might be responsible for costs associated with the cleanup of the site. The agency did not offer details about when the site might be considered completely returned to normal. The N.T.S.B. is still investigating the cause of the derailment.

The Ohio Environmental Protection Agency is working on an assessment for a remediation plan.

“Initially, with most environmental spills, it is difficult to determine the exact amount of material that has been released into the air, water, and soil,” James Lee, media relations manager for the Ohio EPA, wrote in an email to CNN. “The assessment phase that will occur after the emergency is over will help to determine that information.”