Metallobiochemistry of ultratrace levels of bismuth in the rat I. Metabolic patterns of

The number of the applications of bismuth (Bi) is rapidly and remarkably increasing, enhancing the chance to increase the levels to which humans are normally daily exposed. The interest to Bi comes also from the potential of Bi-based nanoparticles (BiNPs) for industrial and biomedical purposes. Like other metal-based NPs used in nanomedicine, BiNPs may release ultratrace amounts of Bi ions when injected. The metabolic fate and toxicity of these ions still needs to be evaluated. At present, knowledge of Bi metabolism in laboratory animals refers almost solely to studies under unnatural "extreme" exposures, i.e. pharmacologically relevant high-doses (up to thousand mg kgRats were intraperitoneally injected with 0.8 μg Bi kg24 h after the administration, the blood concentration of Bi was 0.18 ng mLOn the basis of an environmental biochemical toxicology approach, we have undertaken a study on the metabolic patterns of Bi