Watch the CBS Reports documentary "Toxic Fog: The Aftermath in East Palestine, Ohio" in the video player above.

One year ago, on Feb. 3, 2023, a freight train carrying hazardous chemicals derailed in East Palestine, Ohio. Within two days, first responders had put out the flames, but the story was just beginning.

"I don't think I would ever feel comfortable living back in that town because I don't think that the full extent of the human health risks will ever be exposed," said Jami Wallace, who fled her hometown with her then 2-year-old daughter Kyla.

While the Wallaces and many other residents had evacuated, crews vented and burned off five rail cars carrying vinyl chloride, a highly combustible gas used to make plastic and other synthetic materials. The Centers for Disease Control and Prevention has linked vinyl chloride to liver injury, neurologic symptoms, dizziness, "visual disturbances," cancer, coma and death.

The decision to conduct the "vent and burn" was made after rail operator Norfolk Southern and its contractors convinced local authorities it was necessary to prevent what could be an even worse catastrophe — an explosion that could send shrapnel flying. The move released a plume of smoke that was so thick, it appeared on National Weather Service satellite images, billowing across Ohio's eastern border into Pennsylvania.

Two days later, evacuees were allowed to return home, but Norfolk Southern relaid its tracks on top of contaminated soil and started running its trains again that night. Some soon began to report symptoms, including rashes, respiratory problems and bloody noses. With residents and local officials demanding accountability, on Feb 21 — nearly 3 weeks after the incident — the U.S. Environmental Protection Agency ordered Norfolk Southern to clean up the contamination left behind.

Since then, the rail operator has employed several contractors to test and sample for contaminants in the environment and homes. One of those contractors is the Center for Toxicology and Environmental Health, or CTEH, a consulting firm that is steeped in controversy. The company has faced lawsuits over its conduct, and lawmakers have criticized corporations for hiring it in previous disasters.

"It's like the fox guarding the henhouse," said Lesley Pacey, an environmental investigator for the Government Accountability Project, a nonprofit that supports whistleblowers and which is suing the EPA to get records on its response to the derailment. "They [CTEH] tend to come up with the result that the polluter would like to see … the BP oil spill, Hurricane Katrina, multiple situations where they went in and didn't find anything wrong."

CTEH tested Wallace's home. Like several other residents who spoke with CBS News, she said they found "nothing." 

She doesn't trust the findings, however, because some of her friends and 47 family members who live in East Palestine are still experiencing symptoms and because CTEH was hired by Norfolk Southern. "I think it's a joke," she said.

Mark Durno, an emergency response supervisor with the EPA, told CBS News that his agency has been closely supervising Norfolk Southern's contractors.

"The primary air monitoring was done by Norfolk Southern's contractor, but every home that was entered, there was also an EPA employee or contractor present to oversee that activity," he said. "The data that we have demonstrates that we were below those levels of concern."

Several independent researchers have taken samples of soil, air and water in the community and say they're getting conflicting results. One of them, Andrew Whelton, a professor of environmental and ecological engineering at Purdue University, said he and his team spent five months investigating the area.

"We didn't find any contamination in drinking water, but chemicals can move slowly underground," he said, adding, "significant contamination was present in buildings and in the creeks. Multiple lines of evidence indicated [the EPA's] public statements were wrong."

Independent scientist Scott Smith, who has conducted testing of the soil, creek water and some residents' furnace filters, alleged that in several locations, he found elevated levels of dioxins, toxic compounds that can form when vinyl chloride is burned.

The EPA's Mark Durno, however, questioned the validity of Smith's sampling and said it hadn't been "validated."

The EPA should have used its own contractors for testing, sampling and cleanup and then billed Norfolk Southern, said Judith Enck, a former regional EPA administrator who has also criticized the decision to vent and burn.

"If you have the polluter doing [the testing and sampling], they have a built-in financial interest in not finding problems," she said. "There's absolutely a conflict of interest."

When asked for a response, CTEH referred CBS News to its website, which says the Arkansas-based company has tested more than 630 homes and businesses in East Palestine and that none of its data suggests risks to human health.

The website also states, "We pride ourselves on accurately representing the facts on any response or project in which CTEH is involved."

Will Harden, senior director of legal claims at Norfolk Southern, told CBS News, "If residents have questions about the test results, I encourage them to come see me or us at the Family Assistance Center [in East Palestine], and if need be, I can reach out to the U.S. EPA."

"I've done that in the past," he added.

When asked whether more independent testers should be involved in the process, Harden said, "I don't have an opinion on that."

In a statement, the EPA told CBS News, "When polluters hire contractors to conduct cleanup work in emergency response and removal action sites, EPA provides full oversight of those actions and, where appropriate, collects independent data."

In East Palestine, the agency said, it "has collected tens of thousands of samples to verify that Norfolk Southern's data is reliable and that the job is done right."

There are lessons to be learned from the disaster response in East Palestine, said Whelton, of Purdue University.

In future disasters, he said, publicly funded experts outside the government should help inform decision-making, and government agencies, from the local to federal levels, need to work better together.

"There was confusion about who's testing what, who's overseeing what, why aren't the numbers, chemical lists and public statements across agencies matching," he said, adding that this is a pattern he has seen in disaster after disaster. "They have no playbook. They wing it every time and chalk it up to experience. That's a foundational problem that's unacceptable."

Many East Palestine residents told CBS News they want to move on and to put the disaster behind them.

But Wallace, who is now renting a home outside East Palestine with the help of Norfolk Southern, said she feels she has a duty to warn other communities about what happened to her hometown.

"If this happens in another community," she said, "at least if my daughter has to watch me die of cancer when she's 10, or God forbid, I have to watch her, at least it saves someone else."

–Nathalie Nieves contributed reporting. 

In:
• Norfolk Southern
• Freight Train Derailment
• Train Derailment
• Ohio