1972 Volume 14 Issue 5 Pages 449-454
Seven healthy male volunteers were exposed through a face mask to SO2 (12-13 ppm), NO2 (14-17 ppm), and the mixture of both gases for 1 hour. Interval between each exposure was approximately 1 week. Immediately before and after the exposure, FEV1.0, Caw (body plethysmo-graphic method) and DLCO (single breath technique) were measured. There was a subject whose Caw/FRC responses were relatively high as compared with other subjects in all the exposures. In 4 subjects, relatively large reductions in Caw/FRC after the exposure to the mixture were observed as compared with its changes by exposure to either SO2 or NO2 alone. After the exposure to SO2-NO2 mixture, the mean of the reduction in Caw/FRC was 0.05 sec-1. cmH2O-1. that was statistically significant, and, although it tended to decrease, the average change in DLCO was not significant.