Toxicological Profiles for Uranium, Radium, and Radon .
Radium is found in soil, water, plants, and food at low concentrations.
People who work at factories that process uranium, work with phosphate fertilizers, or live near uranium mines have a greater chance of being exposed to higher levels of uranium, radium, and radon than the general population. In addition, there is a test that measures the rate of elimination of radium and radon in exhaled breath. Animal studies have reported inflammatory reactions in the nasal passages and kidney damage from acute inhalation exposure to uranium. Acute animal tests, such as the LC 50 and LD 50 tests in rats, mice, and guinea pigs, have shown uranium to have low to moderate toxicity from inhalation exposure and high toxicity from oral exposure. One study reported kidney effects in humans following exposure to uranium, while several other studies have found no increased deaths in uranium workers due to kidney disease.