A FIELD INVESTIGATION OF THE ACUTE RESPIRATORY EFFECTS OF METAL-WORKING FLUIDS .1. EFFECTS OF AEROSOL EXPOSURES

A study of cross-shift change in pulmonary function was conducted amon g workers exposed to metal working fluids (MWF) in an automobile parts manufacturing company. Three hundred eight-six workers (216 machinist s exposed to straight or soluble MWFs, and 170 nonmacinists) were stud ied for 1 day, performing spirometry at the beginning and end of their shift. Airborne concentrations of inhalable particulate, culturable b acteria, and endotoxin were measured. We observed an approximately thr eefold increase in the incidence of 5% or greater cross-shift decremen t in forced expiratory volume during the first second among those with exposures above about 0.15 mg/m(3), compared to those with exposures below about 0.08 mg/m(3). There was some evidence that chronic respira tory symptoms were more prevalent among machinists than among nonmachi nists, notably for chronic cough. Baseline FEB1 was about 3% lower on average among those with soluble MWF exposure compared to nonmachinist s. These findings are consistent with earlier studies showing respirat ory effects of MWFs. (C) 1997 Wiley-Liss, Inc.