US EPA

Anatomically accurate human child and adult nasal tract models will be used in concert with computationally simulated air flow information to investigate the influence of age-related differences in anatomy on inhalation dosimetry in the upper and lower airways. The findings of this research will better characterize available information on human nasal tract dosimetry, including evaluation of the adequacy of the current Agency default dosimetry, especially for the upper airways (i.e., the nasal and nasopharyngeal areas).

This work will advance the Agency’s knowledge of human inhalation dosimetry and the affect of age-related differences in nasal tract anatomy on dosimetry. These findings may be applied to all Agency human inhalation risk assessments. These findings will also be used in the revision of the Agency’s chronic RfC Methodology, in particular the application of uncertainty and dosimetric adjustments. The final deliverable will be a published manuscript.

Garcia, G. J., J. D. Schroeter, R. A. Segal, J. J. STANEK, G. L. FOUREMAN, AND J. S. Kimbell. Dosimetry Of Nasal Uptake Of Soluble And Reactive Gases: A First Study Of Inter-Human Variability (Journal Article). INHALATION TOXICOLOGY. Taylor & Francis, Inc., Philadelphia, PA, 21(7):607-618, (2009).