https://amp.azcentral.com/amp/2876435002
potential uranium exposure
For nearly two decades at the Grand Canyon, tourists, employees, and children on tours passed by three paint buckets stored in the National Park's museum collection building, unaware that they were being exposed to radiation.
Although federal officials learned last year that the 5-gallon containers were brimming with uranium ore, then removed the radioactive specimens, the park's safety director alleges nothing was done to warn park workers or the public that they might have been exposed to unsafe levels of radiation.
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Stephenson said the containers were stored next to a taxidermy exhibit, where children on tours sometimes stopped for presentations, sitting next to uranium for 30 minutes or more. By his calculation, those children could have received radiation dosages in excess of federal safety standards within three seconds, and adults could have suffered dangerous exposure in less than a half-minute.