Peripheral Airway Responses to Acute Hair-Spray Exposure

Abstract

The acute phase of a longitudinal study of pulmonary function responses to a hair-grooming aerosol included determinations of lung and forced expiratory volumes, derivatives of maximal expiratory flow-volume (MEFV) curves, closing volume information and the slope of the alveolar plateau (phase III) before and 1, 3 and 5 min after a 20-s application of the spray to 30 healthy subjects. Baseline indices approximated individual prediction standards except for an increased mean slope of the alveolar plateau. After exposure there were meaningful changes in forced vital capacity, forced expiratory volume for the 1st s and the ratio of residual volume to total lung capacity suggestive of a modest bronchodilatation. Closing capacity decreased significantly without changes in the means for CV [closing volume] and the phase III slope. Flow rates at low lung volumes were unaltered except for a significant rise in .ovrhdot.Vmax 50%. Although their control means were alike for all physiologic indices, a post-aerosol decrease in a single flow rate (FEF75%) and a further increase in the phase III slope appeared to differentiate the responses of the 17 smokers from those of the 13 nonsmokers. This single hair-spray exposure did not induce mean changes in terminal flow rates or measurable effects on other tests for the entire group indicative of peripheral airway constriction. The same subjects are having serial determinations made during 1 yr of daily use of the same product.