The effect of ozone exposure on the dispersion of inhaled aerosol boluses in healthy human subjects

Journal Article · Mon Jul 01 00:00:00 EDT 1991 · American Review of Respiratory Disease (New York); (United States)

DOI:https://doi.org/10.1164/ajrccm/144.1.23· OSTI ID:5447886

Keefe, M J; Bennett, W D; DeWitt, P; Seal, E; Strong, A A; Gerrity, T R ^[1]

---

1. Clinical Research Branch, U.S. Environmental Protection Agency, Research Triangle Park, NC (USA)

Acute exposure of humans to low levels of ozone are known to cause decreases in FVC and increases in SRaw. These alterations in lung function do not, however, elucidate the potential for acute small airway responses. In this study we employed a test of aerosol dispersion to examine the potential effects of ozone on small airways in humans. Twenty-two healthy nonsmoking male volunteers were exposed to 0.4 ppm ozone for 1 h while exercising at 20 L/min/m2 body surface area. Before and immediately after exposure, tests of spirometry (FVC, FEV1, and FEF25-75) and plethysmography (Raw and SRaw) were performed. Subjects also performed an aerosol dispersion test before and after exposure. Each test involved a subject inhaling five to seven breaths of a 300-ml bolus of a 0.5 micron triphenyl phosphate aerosol injected into a 2-L tidal volume. The bolus was injected into the tidal breath at three different depths: at Depth A the bolus was injected after 1.6 L of clean air were inhaled from FRC, at Depth B after 1.2 L, and at Depth C after 1.2 L but with inhalation beginning from RV. The primary measure of bolus dispersion was the expired half-width (HW). Secondary measures were the ratio (expressed as percent) of peak exhaled aerosol concentration to peak inhaled concentration (PR), shift in the median bolus volume between inspiration and expiration (VS), and percent of total aerosol recovered (RC). Changes in pulmonary function after ozone exposure were consistent with previous findings.

• OSTI ID: 5447886
• Journal Information: American Review of Respiratory Disease (New York); (United States), Vol. 144:1; ISSN 0003-0805
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
LUNGS
SENSITIVITY
OZONE
TOXICITY
ACUTE EXPOSURE
AEROSOLS
AIR
DYNAMIC FUNCTION STUDIES
EXERCISE
INHALATION
MAN
ANIMALS
BODY
COLLOIDS
DISPERSIONS
FLUIDS
GASES
INTAKE
MAMMALS
ORGANS
PRIMATES
RESPIRATORY SYSTEM
SOLS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology