Institut de radioprotection et de sûreté nucléaire (IRSN)
Laboratoire de radiotoxicologie et radiobiologie expérimentale (LRTOX)
31, avenue de la Division Leclerc
92262 Fontenay-aux-Roses Cedex
- Key words: three-dimensional microtomography, uranium, chronic contamination, bone
- DOI : 10.1684/ers.2017.1119
- Page(s) : 31-9
- Published in: 2018
Uranium is a radioactive heavy metal naturally present in the environment. Its recent use in various civilian and military applications sometimes result in its release into the environment. After chronic ingestion, uranium accumulates in various organs, preferentially in bones. Several studies have shown that exposure to high concentrations of uranium affects bone growth. Little is known, however, about the effects of chronic exposure to low doses of uranium on bone, especially when ingested via drinking water, the main route by which the public is exposed to this radionuclide. This study examined the effects of chronic exposure to natural uranium through drinking water on bone integrity and bone turnover. Rats were contaminated with different concentrations of natural uranium (15, 10, and 40 mg / l) for 9 months. A high-resolution three-dimensional microtomography scanner was used for the first time to study uranium's impact on bone metabolism and thus on bone tissue integrity. After nine months of uranium exposure, microarchitecture analysis revealed that the cortical bone diameter of the femoral diaphysis of rats contaminated at a concentration of 40 mg/L of uranium had decreased significantly.
In conclusion, our findings that chronic ingestion of uranium at low concentrations affects growth of cortical bone width suggests that it may affect bone strength. These results thus suggest the need to pay special attention to children during chronic low-dose exposure to this radionuclide.