Deposition of ultrafine aerosols in rat nasal molds

Journal Article · Mon Jan 01 00:00:00 EST 1990 · Toxicology and Applied Pharmacology; (United States)

DOI:https://doi.org/10.1016/0041-008X(90)90242-M· OSTI ID:7013416

Cheng, Y S; Hansen, G K; Su, Y F; Yeh, H C ^[1]; Morgan, K T ^[2]

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1. Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States)
2. Chemical Industry Institute of Toxicology, Research Triangle Park, NC (United States)

To evaluate the health effect of air pollutants on the respiratory tract, it is critical to determine the regional deposition of inhaled aerosols. Information on deposition of larger particles in the nasal passages of laboratory animals is available; the deposition fraction increases with increasing particle size. However, little deposition information is available for ultrafine particles of less than 0.2 {mu}m. Three clear, plastic molds (models) of the nasal passages of F344/N rats, prepared from metal replica casts used in these studies. Total deposition of ultrafine aerosols in the casts was determined by using a unidirectional flow system. The pressure drops measured in the casts were a function of flow rate to the power of 1.4-1.6, indicating that flow through the nasal passages has nonlaminar components. Deposition data were obtained by using monodisperse sodium chloride aerosols with particle sizes ranging from 0.2 to 0.005 {mu}m, at inspiratory and expiratory flow rates of 200 to 600 ml/min. Similar deposition data were obtained for two of the casts studied. Deposition efficiency was greatest for the smallest particles, and decreased with increasing particle size and flow rate. At an inspiratory flow rate of 400 ml/min, which is comparable to the mean respiratory flow of an adult male F344 rat with a respiratory minute volume of 200 ml, deposition efficiencies reached 40 and 70% for 0.01- and 0.005-{mu}m particles, respectively.

• DOE Contract Number: AC04-76EV01013
• OSTI ID: 7013416
• Journal Information: Toxicology and Applied Pharmacology; (United States), Vol. 106; ISSN 0041-008X
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AEROSOLS
INHALATION
RESPIRATORY SYSTEM
SENSITIVITY
AIR POLLUTION
BIOLOGICAL EFFECTS
PARTICLE SIZE
RATS
RESPIRATION
STRUCTURAL MODELS
UPTAKE
ANIMALS
COLLOIDS
DISPERSIONS
INTAKE
MAMMALS
POLLUTION
RODENTS
SIZE
SOLS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology