Acute exposure to acid fog. Effects on mucociliary clearance

Journal Article · Sat May 01 04:00:00 EDT 1993 · American Review of Respiratory Disease; (United States)

DOI:https://doi.org/10.1164/ajrccm/147.5.1105· OSTI ID:6524644

Laube, B L; Bowes, III, S M; Links, J M; Thomas, K K; Frank, R ^[1]

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1. Johns Hopkins Univ. School of Hygiene and Public Health, Baltimore, MD (United States)

Submicrometric sulfuric acid (H2SO4) aerosol can affect mucociliary clearance without eliciting irritative symptoms or changes in pulmonary function. The effect of larger fog droplets containing H2SO4 on mucociliary clearance is unknown. We quantified mucociliary clearance from the trachea (n = 4) and small airways (n = 7) of young healthy male adults after an acute exposure to H2SO4 fog (MMAD = 10.3 microns; pH = 2.0; liquid water content = 481 +/- 65 mg/m3; osmolarity = 30 mOsm). Acid fog (AF) or saline fog (SF) (10.9 microns; 492 +/- 116 mg/m3; 30 mOsm) was administered for 40 min of unencumbered breathing (no mouth-piece) at rest and for 20 min of exercise sufficient to produce oronasal breathing. Fog exposures were followed by a methacholine (MCh) challenge (a measure of airway reactivity) or inhalation of technetium-99M radioaerosol (MMAD = 3.4 microns) on 2 study days each. Changes in symptoms and forced ventilatory function were also assessed. Clearance was quantified from computer-assisted analyses of gamma camera images of the lower respiratory tract in terms of %removal/min of the radiolabel from the trachea 25 min after inhalation and from the outer zone of the right lung after 1.9 to 3 h. Symptoms, forced ventilatory function, and MCh response were unaffected by either fog. Tracheal clearance was more rapid in four of four subjects after AF (0.83 +/- 1.58% removal/min) compared with that after SF (-0.54 +/- 0.85% removal/min). Outer zone clearance was more rapid in six of seven subjects after AF (0.22 +/- 0.15% removal/min) compared with that after SF (0.01 +/- 0.09% removal/min).

• OSTI ID: 6524644
• Journal Information: American Review of Respiratory Disease; (United States), Journal Name: American Review of Respiratory Disease; (United States) Vol. 147:5; ISSN ARDSBL; ISSN 0003-0805
• Country of Publication: United States
• Language: English

Related Subjects

550501 -- Metabolism-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACUTE EXPOSURE
AEROSOLS
AIR POLLUTION
BIOLOGICAL EFFECTS
BRONCHI
CLEARANCE
COLLOIDS
DISPERSIONS
ELEMENTS
FOG
HYDROGEN COMPOUNDS
INHALATION
INORGANIC ACIDS
INTAKE
ISOTOPE APPLICATIONS
MALES
METALS
PARTICLE SIZE
POLLUTION
RESPIRATORY SYSTEM
SIZE
SOLS
SULFURIC ACID
TECHNETIUM
TRACER TECHNIQUES
TRACHEA
TRANSITION ELEMENTS
WEATHER