An evaluation of respiratory effects following exposure to 2.0 ppm formaldehyde in asthmatics: lung function, symptoms, and airway reactivity.
Fifteen asthmatic volunteers were exposed in a double-blind, random manner to room air and 2.0 ppm formaldehyde for 40 min in an environmental chamber. These exposures were repeated on a separate day during moderate exercise (450 kpm/min) for 10 min. Ambient and dew point temperatures were 23.0 +/- 0.0 degrees C and 11.5 +/- 1.0 degrees C, respectively. No significant airway obstruction as measured by flow-volume parameters and airway resistance was noted in this group during or immediately after exposure. Furthermore, sequential measurements of peak flow for 24 hr following formaldehyde exposure revealed no delayed airway response. In contrast, in comparison to the baseline methacholine inhalation challenge (MIC) test on the screening day, 8 of 12 asthmatics demonstrated a lower threshold to MIC following 2.0 ppm exposure for 40 min; however, the mean and median decrements of threshold in methacholine concentration of 10.4 mg/ml and 24.3 mg/ml were not significant (p = .12). Bad odor, sore throat, and eye irritation were common during exposure but symptoms were infrequent afterward.
Witek
T J
TJ
Mount Sinai Medical Center, New York, New York.
Schachter
E N
EN
Tosun
T
T
Beck
G J
GJ
Leaderer
B P
BP
D000328:Adult; D000403:Airway Resistance; D001249:Asthma / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D004311:Double-Blind Method; D005260:Female; D005557:Formaldehyde / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008448:Maximal Expiratory Flow Rate; D016210:Methacholine Chloride; D008688:Methacholine Compounds; D010366:Peak Expiratory Flow Rate; D005082:Physical Exertion; D012129:Respiratory Function Tests; D014797:Vital Capacity
D008688:Methacholine Compounds; D016210:Methacholine Chloride; D005557:Formaldehyde