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Olfactory transport of represents an important mechanism for direct delivery of certain metals to the central nervous system (CNS). The objective of this study was to determine whether inhaled tungsten (W) undergoes olfactory uptake and transport to the rat brain. Male, 16-week-old, Sprague–Dawley rats underwent a single, 90-min, nose-only exposure to a Na
2
188WO
4 aerosol (256
mg
W/m
3). Rats had the right nostril plugged to prevent nasal deposition of
188W on the occluded side. The left and right sides of the nose and brain, including the olfactory pathway and striatum, were sampled at 0, 1, 3, 7, and 21 days post-exposure. Gamma spectrometry (
n
=
7 rats/time point) was used to compare the levels of
188W found on the left and right sides of the nose and brain and blood to determine the contribution of olfactory uptake to brain
188W levels. Respiratory and olfactory epithelial samples from the side with the occluded nostril had significantly lower end-of-exposure
188W levels confirming the occlusion procedure. Olfactory bulb, olfactory tract/tubercle, striatum, cerebellum, rest of brain
188W levels paralleled blood
188W concentrations at approximately 2–3% of measured blood levels. Brain
188W concentrations were highest immediately following exposure, and returned to near background concentrations within 3 days. A statistically significant difference in olfactory bulb
188W concentration was seen at 3 days post-exposure. At this time,
188W concentrations in the olfactory bulb from the side ipsilateral to the unoccluded nostril were approximately 4-fold higher than those seen in the contralateral olfactory bulb. Our data suggest that the concentration of
188W in the olfactory bulb remained low throughout the experiment, i.e., approximately 1–3% of the amount of tungsten seen in the olfactory epithelium suggesting that olfactory transport plays a minimal role in delivering tungsten to the rat brain.