Accession Number:

AD1173650

Title:

Intranasal Deposition of Dry Particles in Anatomically Correct Physical Models of Children and Adults during Inspiratory Flow Rates Representing Sitting Awake, Light Activity, and Light and Heavy Exercise

Descriptive Note:

[Technical Report, Final Report]

Corporate Author:

Combat Capabilities Development Command Chemical Biological CenterOak Ridge Institute for Science and EducationExcet, IncCFD Research CorporationThe Johns Hopkins Medical Institutions

Report Date:

2022-07-07

Pagination or Media Count:

30

Abstract:

Physical models of the respiratory system provide a method for quantifying particle deposition in humans without exposing them to toxic agents. Although particles may be liquid or dry, little is known about intranasal deposition of dry particles within models. We compared intranasal deposition of 0.5810 micrometers particles of test dust in models of 2-, 5-, and 18-year-old humans at flow rates representing sitting awake SA, light activity LA, light exercise LE, and heavy exercise HE. Intranasal deposition increased with particle size and airflow rate, and deposition for the 18-year-old model agreed with published in vivo results in adults. For SA conditions, intranasal deposition was significantly greater in the 2- and 5-year-old models than in the 18-year-old model for particles less than or equal to 3.52 micrometers. Under LA, LE, and HE breathing conditions, intranasal deposition of most particles Greater than or equal to 2.46 micrometers was significantly greater in the 18-year-old model as compared to the 5-year-old model. This study is the first to show that intranasal deposition of dry particles between 0.58 and 3.52 micrometers may be greater in children less than or equal to 5 years old during SA, as compared to adults. Information from this study could inform future policies designed to protect children from exposure to inhaled toxic particles.

Descriptors:

Subject Categories:

  • Medicine and Medical Research

Distribution Statement:

[A, Approved For Public Release]