Regional aerosol deposition in human upper airways [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 1991.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Physical Description:
- Pages: (10 pages) : digital, PDF file
- Additional Creators:
- Johns Hopkins University
United States. Department of Energy
United States. Department of Energy. Office of Scientific and Technical Information
- During the current report experimental studies of upper respiratory deposition of radon progeny aerosols and stimulant aerosols were carried out in replicate casts of nasal and oral passages of adults and children. Additionally, preliminary studies of nasal passage deposition of unattached Po²¹⁸ particles was carried out in four human subjects. Data on nasal inspiratory deposition in replicate models of adults and infants from three collaborating laboratories were compared and a best-fit curve of deposition efficiency for both attached and unattached particles was obtained, showing excellent inter-laboratory agreement. This curve demonstrates that nasal inspiratory deposition of radon progeny is weakly dependent upon flow rate over physiologically realistic ranges of flow, does not show a significant age effect, and is relatively independent of nasal passage dimensions for a given age range. Improved replicate models of the human adult oral passage extending to the mid-trachea were constructed for medium and higher flow mouth breathing states; these models were used to assess the deposition of unattached Po²¹⁸ particles during oronasal breathing in the oral passage and demonstrated lower deposition efficiency than the nasal passage. Measurements of both Po²¹⁸ particle and attached fraction particle size deposition were performed in replicate nasal passage of a four week old infant. 5 refs., 1 fig.
- Published through SciTech Connect.
- Funding Information:
View MARC record | catkey: 13814613