FLAGSTAFF, Arizona: United States officials are investigating reports that visitors to the Grand Canyon National Park museum could have been exposed to high levels of uranium radiation for nearly two decades, American media reported.

The investigation comes after the park's safety, health and wellness manager discovered three five-gallon buckets of uranium ore at the museum building in June last year, reported CNN.



The toxic buckets had been stashed next to the taxidermy exhibit in the park’s museum for nearly 20 years, the manager, Elston Stephenson, told CNN.

Stephenson told CNN that he immediately alerted the park’s service radiation specialist after discovering the uranium ore, and that test results near the buckets later came back positive for radioactivity above background levels.

Elsewhere, radiation levels were not elevated, CNN reported.

Arizona Republic cited him as saying that technicians later dumped the uranium ore at the nearby Lost Orphan mine, an old uranium dig, and brought the empty buckets back to the park.



Stephenson also claimed that he had tried for months to get National Park Service officials to inform employees and the public about possible uranium exposure, but was ignored.

He then filed a complaint with the Occupational Safety and Health Administration (OSHA) in November, which sent inspectors to the museum building.

The reports cited an OSHA spokesperson as saying that it has opened an investigation.

The National Park Service is also investigating the matter and working with the OSHA and the Arizona Department of Health Services, according to the reports.

Stephenson decided to blow the whistle in an email to Park Service employees on Feb 4, Arizona Republic reported, to warn them of possible health consequences.

"If you were in the Museum Collections Building (bldg 2C) between the year 2000 and Jun 18, 2018, you were 'exposed' to uranium by OSHA's definition,” Stephenson wrote in the email.

"Please understand, this doesn't mean that you're somehow contaminated, or that you are going to have health issues. It merely means essentially that there was uranium on the site and you were in its presence ... And by law we are supposed to tell you," he continued.

Uranium occurs naturally in the rocks of the Grand Canyon National Park, US authorities told CNN. Citing a survey, it added that the radiation has been found to be at “background” levels, meaning that they are always present in the environment but below levels of concern. It also said that there is no current risk to the public or park employees.

The museum collection facility remains open and employees are working as normal, reports said.