The US Environmental Protection Agency has identified three more chemicals that were released when a cargo train derailed in East Palestine, Ohio.
The Norfolk Southern train was shipping cargo from Illinois to Pennsylvania when it derailed in Ohio last week.
About 50 cars of the 140-car train were derailed. Ten of the cars contained hazardous materials.
The derailment triggered the small release of vinyl chloride, a hazardous chemical that is used to make plastic PVC pipes.
About 2,000 residents were placed under evacuation orders and a shelter-in-place was ordered for the entire town.
The EPA on Sunday posted a notice that additional chemicals had been found — glycol monobutyl, isobutylene and ethylhexyl acrylate.
The agency in a letter also notified Norfolk Southern of its potential liability for the incident and that it would have to reimburse the federal agency for clean-up efforts.
And two residents filed a lawsuit last week in an attempt to force the rail company to establish health monitoring for residents in Ohio and Pennsylvania.
The lawsuit would require Norfolk Southern to pay for screenings and medical care for any people affected by the release of the toxic substances within a 48-kilometre radius.
East Palestine will hold a town hall on Wednesday for residents to ask questions related to the train derailment.
The Associated Press contributed to this report
