Sulfuric acid aerosol followed by ozone exposure in healthy and asthmatic subjects

Journal Article · Sat Apr 01 04:00:00 EST 1995 · Environmental Research

DOI:https://doi.org/10.1006/enrs.1995.1020· OSTI ID:258873

Frampton, M W; Morrow, P E; Cox, C ^[1]

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1. Univ. of Rochester School of Medicine and Dentistry, NY (United States); and others

These studies evaluated symptom and pulmonary function responses of humans sequentially exposed to sulfuric acid aerosol and ozone. Thirty healthy subjects and 30 allergic asthmatic subjects underwent 3-hr exposures in an environmental chamber to 100{mu}g/m{sup 3} sulfuric acid and sodium chloride (control) aerosols (in random order), followed 24 hr later by 3-hr exposures to ozone (0.08, 0.12, or 0.18 ppm). Each subject was studied four times, receiving each aerosol preexposure followed by two of the three ozone concentrations. For the healthy group, no convincing symptomatic or physiologic effects of exposure to either the aerosol or ozone on lung function were found. For the asthmatic group, preexposure to sulfuric acid altered the pattern of response to ozone in comparison with sodium chloride preexposure and appeared to enhance the small mean decrements in FVC that occurred in response to 0.18 ppm ozone (means {+-}SE: -3.6 {+-}1.5% with sodium chloride preexposure, -6.8 {+-} 1.7% with sulfuric acid preexposure). Individual responses among asthmatic subjects were quite variable, some demonstrating reductions in FEV of more than 35% following ozone exposure. Analysis of variance of changes in FVC revealed evidence for interactions between aerosol and ozone exposure both immediately after (P = 0.005) and 4 hr after (P = 0.030) exposure. Similar effects were seen for FEV. When normal and asthmatic subjects were combined, four-way analysis of variance revealed an interaction between ozone and aerosol for the entire group (P = 0.0022) and a difference between normal and asthmatic subjects (P = 0.0048). There was no significant effect of exposures on symptoms for either normal or asthmatic subjects. Asthmatic subjects differ from healthy volunteers in their functional responses following sequential exposures to aerosols and ozone and appear to represent a susceptible population. 33 refs., 6 figs., 4 tabs.

• OSTI ID: 258873
• Journal Information: Environmental Research, Journal Name: Environmental Research Journal Issue: 1 Vol. 69; ISSN ENVRAL; ISSN 0013-9351
• Country of Publication: United States
• Language: English

Related Subjects

56 BIOLOGY AND MEDICINE
APPLIED STUDIES
AEROSOLS
BIOLOGICAL EFFECTS
MAN
OZONE
RESPIRATORY SYSTEM
RESPIRATORY SYSTEM DISEASES
RESPONSE MODIFYING FACTORS
SULFURIC ACID