EAST PALESTINE, Ohio — Eleven days after a train derailed, spilling toxic chemicals and causing a massive fire here, officials told residents Tuesday to use bottled water until testing could confirm whether the local water supply was safe to drink — heightening concern among some locals who were already wary of returning to their homes.

As questions continued to swirl around the cause of the Feb. 3 accident and the official response to it, the disaster’s still-emerging list of effects became more clear: Water officials are tracking a large plume of contamination flowing down the Ohio River; about 3,500 fish in local waterways have been killed by the chemical release; and cleanup crews are excavating a “grossly contaminated” 1,000-foot area around the train tracks where butyl acrylate puddled and vinyl chloride burned.

“For right now, I think bottled water’s the right answer,” Ohio Health Director Bruce Vanderhoff said at a news conference Tuesday.

Along with wondering about their drinking water, many residents pondered their options as a strong odor of chemicals continued to hang over the town. Some locals said they are considering leaving East Palestine and are frustrated with how little they know about their potential exposure to toxic chemicals.

Bodiah Cepin, 21, showed up at a local assistance center Tuesday and said he has spent time online researching ethylhexyl acrylate, one of the toxic chemicals that leaked out from the crash site.

“I’ve got my eye on moving somewhere else because I am young and it will take years to clean this up,” said Cepin, who evacuated the area and has been staying with his father outside of Pittsburgh. “Even a minute size of ethylhexyl can stay in the soil for years.”

A mechanical issue probably caused the Norfolk Southern train to derail near the Ohio-Pennsylvania border, federal investigators have said, suddenly hitting the small town with a pollutant-laden fire, the threat of an explosion and the release of at least six toxic chemicals. Officials now face the task of assessing how much contamination has seeped into the ground, soil and water.

Ohio state officials on Tuesday focused on reassuring residents that the air in East Palestine remains safe to breathe and that those who evacuated last week can live in their homes. Despite the extent of the cleanup ahead, officials indicated new contamination wasn’t happening.

The plume flowing down the Ohio River is being diluted as it moves and is not expected to taint any drinking water, Tiffani Kavalec, head of surface water for the Ohio Environmental Protection Agency, said at the briefing. In addition, fish are not continuing to die, said Mary Mertz, director of the Ohio Department of Natural Resources, indicating that new contamination isn’t flowing into the local waters.

On Tuesday morning, East Palestine was quiet except for the hum of industrial equipment. At the site of the accident, cleanup workers were using cranes and other heavy machinery, hauling sheets of metal by hand, and moving wreckage into dumpsters — pausing their work whenever a train came through.

“Please Pray for EP,” read a sign at the Dairy Mill, an ice cream shop closed for the season.

Ohio Gov. Mike DeWine (R) told reporters that Norfolk Southern had committed to paying “for everything” and said the state would hold the rail company responsible.

“The impact on this community is huge. Not just the physical problem that might be caused, but the inconvenience, the terror,” DeWine said. “I understand people’s skepticism and I understand their anger, and if I lived in the community, I would be angry, too.”

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The train was not categorized as a high-hazardous material train, DeWine said, meaning the railroad company wasn’t required to give the state any notification about its passage. The governor called on Congress to reexamine regulations for trains carrying toxic substances, something some environmental advocates have long pushed for.

Norfolk Southern said Monday that it has paid out more than $1 million to displaced residents in “reimbursements and cash advances” for lodging and other expenses and is “in the process of contacting and meeting with affected local businesses.” The company also donated money to the Ohio Red Cross and the local fire department.

Twenty cars of the 141-car train were carrying hazardous materials, 11 of which derailed, the National Transportation Safety Board reported Tuesday, along with other cars carrying cargo not categorized as hazardous. When the train derailed, federal investigators and chemical safety experts immediately homed in on a toxic and highly flammable gas being transported in five of the cars: vinyl chloride.

Afraid the train cars would explode, sending shrapnel into neighborhoods, authorities decided the better of “two bad options” was to release and burn the vinyl chloride, DeWine said Tuesday. The move sent dangerous gases, hydrogen chloride and phosgene, into the air, but averted an explosion that DeWine said he had been told would be “catastrophic.”

Residents for days have wondered what else leaked from the train, and information has emerged slowly. The U.S. Environmental Protection Agency said last week that several more toxic chemicals were on board, which the agency confirmed Sunday when it published a list from Norfolk Southern showing which rail cars had been breached.

Vinyl chloride and butyl acrylate were the primary chemicals that were released, Ohio EPA spokesman James Lee told The Washington Post on Tuesday. The others included ethylene glycol monobutyl ether and ethylhexyl acrylate.

Neither government agencies nor the railroad has detailed what quantity of the chemicals was released into the air or how much spilled on the ground.

“I wouldn’t want to be exposed to any of them in significant amounts,” Erik D. Olson, a senior strategic director at the Natural Resources Defense Council, an environmental advocacy group, said in an email. “They all pose hazards if inhaled.”

Ethylene glycol monobutyl ether, a combustible liquid that’s used commercially as a solvent in spray lacquers and latex paint and is an ingredient in paint thinner, can cause irritation of the eyes and nose, headache, and vomiting in people exposed to it at high levels, according to the federal Agency for Toxic Substances and Disease Registry. On the railway’s list, the status of this chemical is listed as “unknown.”

Exposure to large amounts of the other three chemicals, two of them liquid and one, isobutylene, a flammable gas, is also known to cause headaches, nausea and respiratory problems. The car carrying isobutylene was not breached.

“The whole thing was a little bit of a toxic soup,” said David Masur, executive director of the advocacy group PennEnvironment. “It feels a little like a sci-fi movie when you are told that one of the byproducts being released is an agent that we used against our enemies in World War I,” he added, referring to phosgene.

Whether the air is now safe to breathe largely depends on whether chemicals are still being emitted, experts have said. Because residents can smell odors and have reported symptoms such as headache and nausea, which are consistent with what some of the chemicals can trigger, some remain uneasy.

The EPA has said that no concerning levels of toxins have been detected in the air, though some experts cast doubt on the initial measurements, telling The Post the testing should have been more robust. Officials at the governor’s briefing said residents should be confident in the data coming from authorities.

After a fire or chemical release ends, the air eventually becomes clear, experts said, and the contamination concern shifts to what is on the ground or could have gotten into the soil. State and EPA officials have said that the chemicals being cleaned up can emit smells even when at levels not deemed hazardous to inhale.

“What’s really important is that the government officials are monitoring the levels to make sure that they’re safe and clearly communicating that,” environmental epidemiologist Lynn R. Goldman, dean of public health at George Washington University and a former EPA official. “But if you’re smelling these odors and they’re making you feel sick, I would want to be somewhere else.”

At the news briefing, officials said anyone experiencing symptoms should call their doctor.

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On Feb. 3, Travers and Tangie Mohrbacher saw fire from their front porch, a mile and a half from the accident site.

“What I was feeling was disbelief as it got bigger and bigger,” recalled Tangie Mohrbacher, 45.

“Nothing happens here,” she added. “It’s East Palestine, Ohio.”

But like many small U.S. towns, this village has train tracks running through it, and they are busy.

Environmental advocates have long warned about the dangers of trains freighting hazardous chemicals. Meanwhile, some in the Republican Party’s right wing have used the incident to criticize the Biden administration and, in particular, Transportation Secretary Pete Buttigieg.

“Another transportation failure under Mayor Pete’s leadership,” tweeted Rep. Andy Biggs (R-Ariz.), one of the central players in the effort to block Rep. Kevin McCarthy’s bid for House speaker.

J.D. Vance, Ohio’s new Republican senator, released a statement Monday raising questions about the quality of the braking system used on the train and the Transportation Department’s approach to regulating the rail system.

DeWine said that President Biden had last week offered federal assistance but that the state had not needed to take Biden up on that offer. White House spokeswoman Karine Jean-Pierre told reporters Tuesday that the administration was “in close touch with local officials to ensure that they have what they need and that their needs are being met.”

Buttigieg weighed in Monday evening. “I continue to be concerned about the impacts of the Feb 3 train derailment near East Palestine, OH, and the effects on families in the ten days since their lives were upended through no fault of their own,” he wrote on Twitter.

In downtown East Palestine, Melissa James on Tuesday reopened her store, Manetta’s Furniture & Décor, for the first time since the train derailment.

She left with her fiancé Jared Clark and his son, who is afflicted with myotonic dystrophy and is autistic. They fled to a hotel for several days but frequently returned for medical supplies and specialty items.

Standing outside the store, she and Clark, 45, said they weren’t sure they will stay in East Palestine. “I am still in a state of shock,” said James.

As for the Mohrbachers, they evacuated with their 13- and 18-year-old children and have since returned — still unsure about the safety of returning home, but hopeful.

“We have trust in our elected officials and the people above them,” said Tangie, referring to local leaders. “We think it’s safe to stay here until they tell us not to.”

The Washington Post’s Rebecca Kiger in East Palestine and Missy Ryan in Washington contributed to this report.

previous coverage

• Residents wonder whether it’s safe to return after toxic train derailment in Ohio

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