CROSS-SECTIONAL FOLLOW-UP OF A FLU-LIKE RESPIRATORY ILLNESS AMONG FIBERGLASS MANUFACTURING EMPLOYEES - ENDOTOXIN EXPOSURE ASSOCIATED WITH 2DISTINCT SEQUELAE

Over a period of 10 years, employees in a manufacturing plant experien ced sporadic flu-like episodes after work in a basement containing a r ecirculated washwater mist. We report a cross-sectional study to defin e the flu-like illness and bioaerosol exposures. High concentrations o f gram-negative bacteria (GNB) (>10(7) cfu/ml) and endotoxin (range 34 -46 mu g/ml) were found in the water. Mist contained >10(3) cfu/m(3) o f GNB, and endotoxin up to 13,900 to 27,800 ng/m(3). Few fungi and the rmotolerant Bacillus species and no Actinomycetes, Legionella species, or amoeba were found in washwater. Airborne levels of fungi were of t he same species and magnitudes as outdoor samples. Subjects volunteere d (n = 28) because of a history of flu-like symptoms or were randomly selected (n = 102) from workers with and without current exposure to t he basement. No acute cases were examined. Cases did not fulfill crite ria for hypersensitivity pneumonitis (HP) and high levels of Ige antib odies to water-borne antigens were not observed. However, among 20 sub jects indicating a history of severe flu-like episodes (severe basemen t flu, SBF), diffusion capacity (DL(CO)) was significantly lower (p = 0.015) than among other workers. The prevalence of SBF was independent of smoking. Cases occurred in clusters, and SBF was more common among workers with intermittent exposure to the basement (19 cases) than wi th daily exposure (1 case). These findings suggest that SBF and associ ated chronically depressed DL(CO) resulted from toxic injury following high-level endotoxin exposure. Asthma was prevalent in the study popu lation, particularly among employees with daily, rather than intermitt ent, exposure to endotoxin-containing mist (odds ratio 6.7, p=0.02). T hus, endotoxin exposure in this study was associated with two distinct sequelae depending on the temporal pattern of exposure. (C) 1995 Wile y-Liss, Inc.