BRONCHOALVEOLAR LAVAGE FINDINGS IN FIREFIGHTERS

Firefighters are exposed to irritating, asphyxiating toxic gases and a erosols. Previous studies indicate that this may result in acute as we ll as chronic lung function impairment. It is well known that inhalati on of organic material can cause alveolitis. The purpose of this study was to investigate whether firefighters repeatedly exposed to fire ga ses and other combustion products develop inflammatory changes in the lower airways and, if so, what subtype of cells and soluble components accumulate. Thirteen nonsmoking firefighters underwent bronchoalveola r lavage (BAL), and the results were compared to a reference group of 112 nonsmoking healthy volunteers. The firefighters showed lower recov ery of instilled lavage fluid (61% vs 72%; P < 0.01) and an increase i n the proportion of lymphocytes in that fluid (8.2% vs 5.7%; P < 0.05) . Alveolar macrophage fluorescence, which is a sign of uptake of inhal ed fluorescent material, rather than a reflection of the degree of inf lammation, was increased in two firefighters. Further, the lavage flui d had higher concentrations of native fibronectin (34.6 vs 22.0 mu g/L ; P < 0.01) and hyaluronic acid (27.7 vs 10.0 mu g/L; P < 0.05). This may indicate local cell activation, since the alveolar capillary membr ane probably was intact, as indicated by an unaffected albumin concent ration. The observed changes in the deep airways are probably caused b y exposure to smoke. It cannot be concluded whether these changes are permanent or are part of a natural temporary defense mechanism. (C) 19 97 Wiley-Liss, Inc.