The navajo people did not have a word for radioactivity and did not know about the dangers of radiation in the 1940s when mining companies began surveying their land. Today the mines are closed but their toxic legacy persist in contaminated soil and drinking water with elevated levels of radiation. There are still over 500 abandoned mines scattered throughout the Navajo land posing serious health risks include lung cancer from inhalation of radioactive particles, as well as bone cancer and impaired kidney function.