Di. Bernstein et al., MACHINE OPERATORS LUNG - A HYPERSENSITIVITY PNEUMONITIS DISORDER ASSOCIATED WITH EXPOSURE TO METALWORKING FLUID AEROSOLS, Chest, 108(3), 1995, pp. 636-641
Six auto parts manufacturing workers were referred for evaluation of a
6-week history of work-related dyspnea, cough, and fatigue. Two worke
rs also reported fever and weight loss. All six worked in a machining
area where a waterbased metalworking fluid was used and recirculated u
nder high pressure, thereby creating an aerosol, Chest radiographs rev
ealed pulmonary interstitial infiltrates in four workers. Lung functio
n tests showed that four workers had decreased diffusing capacity. Aft
er removal from the work area, all workers recovered. The metalworking
fluid was cultured for bacteria and fungi. Isolates from broth cultur
es were sonicated to obtain antigen extracts, Serum precipitins to one
or more of the microbial isolates were identified in all six workers
but not in eight of nine nonexposed control subjects. The most frequen
t precipitin response (six of six workers) was against antigens of Pse
udomonas fluorescens, which was cultured from the metalworking fluid.
In all workers, precipitins to at least one other cultured organism we
re detected; these included Aspergillus niger, Staphylococcus capitas,
an acid-fast Rhodococcus sp, and Bacillus pumilus. This represents th
e first report of hypersensitivity pneumonitis associated with industr
ial exposure to aerosolized metal working fluid. Observed precipitin r
esponses to a variety of microbial contaminants in metalworking fluid
strongly suggest a causative role for microbial antigens in the induct
ion and elicitation of this manifestation of hypersensitivity pneumoni
tis.