Laboratory study of asthmatic volunteers exposed to nitrogen dioxide and to ambient air pollution

Journal Article · Fri Apr 01 00:00:00 EST 1988 · Am. Ind. Hyg. Assoc. J.; (United States)

DOI:https://doi.org/10.1080/15298668891379530· OSTI ID:6855880

Avol, E L; Linn, W S; Peng, R C; Valencia, G; Little, D; Hackney, J D

Adult volunteers with moderate to severe asthma (N = 59) underwent dose-response studies to assess their reactivity to nitrogen dioxide (NO/sub 2/) in otherwise clean air. Exposure concentrations were 0.0 (control), 0.3 and 0.6 ppm. A subgroup (N = 36) also underwent exposures to Los Angeles area ambient air at times when NO/sub 2/ pollution was expected. Concentrations of NO/sub 2/ during ambient exposures were 0.086 +/- 0.024 ppm (mean +/- s.d.). All exposures took place in a movable chamber/laboratory facility. Each study lasted 2 hr, with alternating 10 min periods of exercise (mean ventilation rate 40 L/min) and rest. Lung function was measured prior to exposure and after 10 min, 1 hr and 2 hr of exposure. Symptoms were recorded prior to exposure, during exposure and for 1 week afterward. In some subjects bronchial reactivity to cold air was measured 1 hr after the end of exposure and again 24 hr later. Different exposure conditions were presented in randomized order, 1 week apart. No pollutant exposure produced statistically significant changes in lung function, symptoms, or bronchial reactivity, relative to clean air. Ambient air exposures produced the largest (still nonsignificant) mean changes in some lung function tests. Given the physiological and atmospheric variability, negative statistical results do not rule out a small unfavorable effect of ambient pollution on lung function. If any such effect occurred, it was not likely caused by NO/sub 2/. Statistical results remained negative when the analysis was restricted to the 20 subjects with most severe lung dysfunction. In conclusion at least in the Los Angeles area, sensitivity to ambient concentrations of NO/sub 2/ is not common, even among adult asthmatics with moderate to severe disease.

• Research Organization: Univ. of Southern California School of Medicine, Downey (USA)
• OSTI ID: 6855880
• Journal Information: Am. Ind. Hyg. Assoc. J.; (United States), Vol. 49:4
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
ASTHMA
PATHOGENESIS
LUNGS
DYNAMIC FUNCTION STUDIES
NITROGEN DIOXIDE
TOXICITY
AIR POLLUTION
DOSE-RESPONSE RELATIONSHIPS
EXERCISE
EXPOSURE CHAMBERS
LOS ANGELES
BODY
CALIFORNIA
CHALCOGENIDES
DISEASES
FEDERAL REGION IX
NITROGEN COMPOUNDS
NITROGEN OXIDES
NORTH AMERICA
ORGANS
OXIDES
OXYGEN COMPOUNDS
POLLUTION
RESPIRATORY SYSTEM
RESPIRATORY SYSTEM DISEASES
USA
560300* - Chemicals Metabolism & Toxicology
550900 - Pathology