(NewsNation) — The U.S. Environmental Protection Agency told residents near the toxic train derailment in eastern Ohio that it is safe to return home, but residents are alarmed and have concerns, as fish in local bodies of water are dying.

About 50 cars, including 10 carrying hazardous materials, derailed on Feb. 3 in the Ohio village of East Palestine. No one was injured in the derailment that investigators said was caused by a broken axle.

Three days after the accident, authorities burned vinyl chloride inside five tanker cars, sending hydrogen chloride and the toxic gas phosgene into the air. They said that burn was preferable to the threat of a larger explosion if nothing was done.

Environmental regulators have been monitoring the air and water in surrounding communities and have said that so far the air quality remains safe and drinking water supplies have not been affected.

But some residents have complained about headaches and feeling sick since the derailment.

Authorities warned the burning vinyl chloride that was in five