The short-term effects of smoke exposure on the pulmonary function of firefighters

The short-term effects of smoke inhalation have been little studied. This study evaluated whether firefighters experience a significant change in spirometric values following exposure to smoke from a fire. Sixty firefighters from the city of Pittsburgh completed a questionnaire (Medical Research Council) and underwent spirometric testing following exposure to house fires. The group contained 25 current smokers, 14 ever smokers, and 21 never smokers. Firefighters reporting cough, phlegm, breathlessness, and chest illnesses were more likely to be current or ever smokers than never smokers. Mean spirometric data obtained before exposure, after a minimum of four off-duty days, showed the following: FVC, 4.50 +/- 0.60L (90 percent of predicted); FEV1, 3.65 +/- 0.56L (96 percent of predicted); FEV1/FVC, 81 +/- 8 percent (106 percent of predicted); FEF25-75%, 3.71 +/- 1.13L/s (96 percent of predicted); and PEF, 7.95 +/- 1.70L/s (87 percent of predicted). After exposure, spirometry was performed on 22 firefighters. All spirometric values decreased after exposure; however, a significant decline was only seen in two indices, the FEV1 and FEF25-75%. This decline was small (3 to 11 percent). Two firefighters experienced an exaggerated decline in spirometric values after exposure, compared to the group as a whole. Neither age, smoking history, location of firefighting, intensity of smoke exposure, or use of a self-contained breathing apparatus explained the reasons for the greater decline in these two individuals. Thus, while firefighters do experience a small decrease in pulmonary function after exposure to house fires, there appears to be a small subgroup of firefighters who develop more substantial and potentially clinically important decreases in pulmonary function after smoke exposure.