Respiratory responses of young adult asthmatics to sulfur dioxide exposure under simulated ambient conditions
Twenty-four young adult asthmatic volunteers were exposed to 0, 0.25, and 0.50 ppm SO/sub 2/ in random order at 1-week intervals. Exposures, conducted in a controlled-environment chamber at 23/sup 0/C and 90+% relative humidity, lasted 1 hr and incorporated alternating 10-min periods of moderate exercise (mean exercise ventilation about 27 liters/min) and rest. Airway resistance was measured before exposure, after the first exercise period, and near the end of exposure. Forced expiratory performance was measured after the final airway resistance measurement. Exposure-relatable symptoms were recorded before, during, and after exposure periods. None of these measures of response showed statistically significant variation attributable to SO/sub 2/, although small significant increases in resistance attributable to exercise were found. These negative results contrast with previous positive findings in asthmatics exposed to SO/sub 2/ via mouthpiece. The differences may relate to effects of mouthpiece breathing on respiratory defenses, or to interindividual variations in bronchial reactivity to SO/sub 2/.
- Research Organization:
- Univ. of Southern California, Downey
- OSTI ID:
- 5814699
- Journal Information:
- Environ. Res.; (United States), Vol. 29:1
- Country of Publication:
- United States
- Language:
- English
Similar Records
Respiratory responses of exercising asthmatic volunteers exposed to sulfuric acid aerosol
Dose-response study of asthmatic volunteers exposed to nitrogen dioxide during intermittent exercise
Related Subjects
LUNGS
DYNAMIC FUNCTION STUDIES
SULFUR DIOXIDE
BIOLOGICAL EFFECTS
ADULTS
ASTHMA
EXERCISE
MAN
RESPIRATORY SYSTEM
AGE GROUPS
ANIMALS
BODY
CHALCOGENIDES
DISEASES
MAMMALS
ORGANS
OXIDES
OXYGEN COMPOUNDS
PRIMATES
RESPIRATORY SYSTEM DISEASES
SULFUR COMPOUNDS
SULFUR OXIDES
VERTEBRATES
560306* - Chemicals Metabolism & Toxicology- Man- (-1987)