At a busy drive-thru McDonald’s in East Palestine, Ohio, a team of epidemiologists, environmental health scientists and others stood outside Saturday handing out flyers. Each brochure has a survey with a QR code that provides information on how to contact health officials.

Three weeks after a massive train derailment spewed cancer-causing toxic fumes throughout the area, the Centers for Disease Control and Prevention began canvassing high-traffic areas of the Ohio city, encouraging residents to speak up. about your symptoms and long-term health. fears

“We really want to make sure that we’re targeting any potentially affected residents,” Jill Shugart, a senior environmental health specialist with CDC’s Agency for Toxic Substances and Disease Registry, said in an exclusive interview with NBC News. Shugart leads the agency’s response in eastern Palestine.

As the cleanup of the disaster continues, people living in and around the small Pennsylvania border town remain terrified that the chemicals that blanketed the area in a thick plume of smoke are harming their health. Some were diagnosed with bronchitis or reported nausea, rashes, itchy eyes and other unexplained symptoms.

“I’ve had a scratchy throat like everyone else,” Mike Zelenak, a business owner in eastern Palestine, told NBC News. “It gives me a headache.” Zelenak owns property near the accident site and is concerned about the risks of long-term illness.

Stories like Zelenak’s are exactly the kind of information the CDC should be collecting, but on a much larger scale.

CDC staff, along with representatives from the Environmental Protection Agency, FEMA, the federal Department of Health and Human Services, and local government, are working to connect with and learn from anyone whose health may have been affected by the consequences of the derailment.

The surveys include “questions like demographics, where residents live, what kind of health effects they might be experiencing, and trying to come up with a timeline of when they might have been in the area when the incident occurred,” Shugart said. “It’s like putting together a puzzle.”

The response so far, the CDC said, has been positive.

The outreach is expected to move to Pennsylvania in the coming days, and the agency will also focus on the health of first responders at the scene of the derailment. The questionnaires are expected to take around 30 minutes per person. Data collection could continue for up to two weeks.

That suggests that the first answers from the CDC probably won’t be available until more than a month after the derailment.

What are the health risks from exposure to chemicals?

When the Norfolk Southern train derailed on February 3, a highly flammable chemical called vinyl chloride caught fire and began shooting from the scene. It is used to make PVC or polyvinyl chloride pipes and packaging materials. It has also been used in the manufacture of vehicle upholstery, giving off that “new car smell”.

he the EPA says when inhaled in large amounts, vinyl chloride increases the risk of liver cancer.

The CDC can only deploy to areas of the country when states formally request the agency’s help. Shugart said his team received applications from the Ohio and Pennsylvania health departments two weeks after the derailment and was mobilized within days.

CDC staff said they have not yet taken any unusual safety precautions in the area. The team is staying at a hotel 30 miles east of Palestine, in Cranberry Township, Pennsylvania. They say they are drinking the tap water in the hotel.

Meanwhile, “people are anxious and very concerned,” said Dr. Maureen Lichtveld, dean of the University of Pittsburgh School of Public Health. Lichtveld, who previously worked with the Agency for Toxic Substances and Disease Registry, said it’s critical that public health teams at the disaster site engage the community by listening to residents’ concerns and being clear about their action plans.

Community members need to be “part of whatever action we take, part of how to design that action, how to implement that action and disseminate the information,” Lichtveld said. “That is a tremendously important step to decrease the stress that currently exists.”

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jesse kirsch contributed.