In vivo deposition of ultrafine aerosols in the nasal airway of the rat

Journal Article · Thu Jan 31 23:00:00 EST 1991 · Fundamental and Applied Toxicology; (United States)

DOI:https://doi.org/10.1016/0272-0590(91)90117-M· OSTI ID:5314358

Gerde, P; Cheng, Y S; Medinsky, M A ^[1]

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1. Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (USA)

We studied the deposition of ultrafine aerosols, ranging in geometric diameter from 0.005 to 0.1 microns, in the nasal airway of Fischer-344/N rats, at inspiratory flow rates of 200, 300, 400, and 600 ml/min. Simultaneously, we measured the pressure drop across the rat nasal airway. The purpose was to determine whether the in vivo deposition of ultrafine aerosols in the rat nasal airway is the same as the deposition observed in rat nasal casts. At a flow rate of 400 ml/min, corresponding to the normal mean inspiratory flow rate of the rat, deposition efficiency increased from 6 to 58%, when the particle diameter decreased from 0.1 to 0.005 microns. For 0.005-microns-diameter particles, the deposition efficiency decreased from 68 to 52% when the flow rate was increased from 200 to 600 ml/min. These results agree well with those from previous experiments with nasal casts, which indicated that diffusion is the dominant mechanism for deposition of ultrafine aerosols. The pressure drop in the nasal airway of the rat increased almost linearly with flow rate, from 73 Pa at 200 ml/min to 247 Pa at 600 ml/min. These values are within the range of those obtained in previous experiments with nasal casts, although the pressure drop in casts increased as a power greater than 1 with flow rate. The results of our study support the use of nasal airway casts to estimate the in vivo deposition of ultrafine aerosols.

• OSTI ID: 5314358
• Journal Information: Fundamental and Applied Toxicology; (United States), Journal Name: Fundamental and Applied Toxicology; (United States) Vol. 16:2; ISSN 0272-0590; ISSN FAATD
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AEROSOLS
ANIMALS
COLLOIDS
DIFFUSION
DISPERSIONS
DOSE-RESPONSE RELATIONSHIPS
INHALATION
INTAKE
MAMMALS
PARTICLE SIZE
RATS
RESPIRATORY SYSTEM
RETENTION
RODENTS
SENSITIVITY
SIZE
SOLS
TOXICITY
VERTEBRATES