In February, a Norfolk Southern train derailed in East Palestine in the U.S. state of Ohio, releasing toxic smoke that blanketed the area. Seven months later, the problem still haunts local residents.

On September 7, the Environment Protection Agency (EPA) announced a new "work plan" which, for the first time since the derailment, broadens the scope of possible contamination. It outlines a need to "evaluate potential background contaminant sources."

According to the EPA, it regards the work plan as a "double-check" to ensure that contamination did not spread as a result of response activities, while it didn't indicate a concern that contamination from the derailment may have affected a larger area.

However, despite local residents' belief that the contamination had spread and threatened their health, the EPA refused to test their homes.

Hilary Flint, who lives four miles from the derailment site invited experts from Wayne State University to test her soil and inside her home.

"That ended up being the proof that inside my home was affected," Flint said.

Experts discovered ethylhexyl acrylate, a known carcinogen, and vinyl chloride. Both chemicals were being transported on the train at the time of the derailment. They also found dioxins, what some call the fentanyl of chemicals, according to NewsNation.

But the EPA told Flint it couldn't determine whether her property was safe as there was not enough data and comprehensive risk assessment. Regardless, the EPA would not individually test her property.

The problem is not unique to Flint. After the "work plan" was announced, there was anger among residents over the EPA's failure to test their homes.