(CNN) – Authorities have issued a warning to anyone who visited Grand Canyon National Park over the last two decades.
The park’s health and safety manager told CNN that people who visited the park’s museum collections building between the year 2000 and June 18, 2018, were possibly exposed to unsafe levels of uranium.
The uranium ore in question was found in buckets stored next to a taxidermy exhibit at the museum, the manager said.
The National Park Service eventually removed the buckets last June and disposed of its contents in a nearby uranium mine.
But the manager said, the workers who removed the buckets were ill-prepared to do so, and that they returned the buckets to the museum after dumping the ore.
Both the U.S. Department of the Interior and a nuclear engineering expert said that they believe the uranium exposure was unlikely to be hazardous to visitors.
The Interior adds, it’s also working with the Occupational Safety and Health Administration (OSHA) and state officials to investigate what happened.