CDC team got sick while investigating health risks from Ohio toxic train derailment.

A team of seven US government investigators fell ill while studying the health impacts of the February derailment of a train carrying toxic chemicals through East Palestine, Ohio, according to the CDC.

The group, including members of the Epidemic Intelligence Service, were going house-to-house surveying town residents near contaminated areas when they began feeling symptoms including sore throats, headaches, coughing and nausea. The group spent a day working from their hotel, before their symptoms quickly resolved, the agency told CNN.

“Symptoms resolved for most team members later the same afternoon, and everyone resumed work on survey data collection within 24 hours. Impacted team members have not reported ongoing health effects,” a CDC spokesperson told the network.

The public health agency did not initially disclose the team getting sick to the public.

Two contractors working on the derailment for the EPA also reported health symptoms after working in an area with strong odors, CNN reported. The agency said that none of the other more than 100 EPA employees on the scene reported any issues.

More than half of the people in a state survey reported headaches, anxiety, couching, fatigue, and irritated skin after the derailment, according to research released Friday from the Ohio Department of Health.

Officials have said the water and air in East Palestine is safe to consume, despite rampant conspiracies online that following the crash and subsequent decision to conduct a controlled burn of some of the chemicals that were spilled.

On Friday, governor Mike DeWine’s office confirmed 1,900 feet of railroad track at the crash site will be removed to allow for the excavation and removal of contaminated soil, and said testing at 157 private wells showed no contaminated water.

As The Independent reported, public health experts say long-term testing is needed in East Palestine to monitor the potential health effects of exposure to the toxic materials transported by the train that derailed.

“Byproducts from the burn could be very toxic and we don’t know yet know what they are,” Dr Erin Haynes, professor of preventive medicine and environmental health at the University of Kentucky told The Independent. “They have probably settled onto the soil. They’re in the homes on surfaces and they could be in the waterways in the sediments…We do not know the long-term consequences of that exposure.”