Evaluation of the Nose-to-Brain Transport of Different Physicochemical Forms of Uranium after Exposure <i>via</i> Inhalation of a UO4 Aerosol in the Rat

Abstract

BACKGROUND: Health-risk issues are raised concerning inhalation of particulate pollutants that are thought to have potential hazardous effects on the central nervous system. The brain is presented as a direct target of particulate matter (PM) exposure because of the nose-to-brain pathway involvement. The main cause of contamination in nuclear occupational activities is related to exposure to aerosols containing radionuclides, particularly uranium dust. It has been previously demonstrated that instilled solubilized uranium in the rat nasal cavity is conveyed to the brain via the olfactory nerve. OBJECTIVE: ) particles. METHODS: a nose-only system in adult rats. Tissues were subjected to complementary analytical techniques. RESULTS: in the olfactory epithelium. Elemental uranium was detected in precise anatomical regions: olfactory neuron dendrites, paracellular junctions of neuroepithelial cells, and olfactory nerve tracts (around axons and endoneural spaces). CONCLUSION: microparticles. This work contributes to knowledge of the mechanistic actions of particulate pollutants on the brain. https://doi.org/10.1289/EHP4927.