title: Role of underlying pulmonary obstruction in short-term airway response to metal working fluid exposure: a reanalysis.
abstract: BACKGROUND
  Among epidemiologic studies that found evidence for associations between exposures to metal working fluids (MWF) and pulmonary function impairments, one found effects restricted to workers with fixed obstruction at baseline. We reanalyzed a previously published study on MWF exposure and cross-shift pulmonary function to further evaluate this finding.
  
  
  METHODS
  Pulmonary function was measured cross-shift on Monday and Friday in 131 male automotive workers. Quantitative personal MWF exposure data were available. Those with an FEV(1)/FVC ratio of <or=0.72 were considered obstructed.
  
  
  RESULTS
  There was a trend towards increasing incidence of cross-shift decrement in FEV(1) as MWF exposure increased in the full cohort as well as when the results were restricted to the 19 (14.5%) who were obstructed. Those with obstruction were slightly more likely to show decrements in FEV(1) on Fridays. Removing the obstructed subgroup did not appear to substantially weaken the exposure-response relation.
  
  
  CONCLUSIONS
  No important differences were found in cross-shift effects of MWF between obstructed and non-obstructed workers.
authors.affiliation: Department of Work Environment, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA.
authors.forename: Ariana
authors.initials: A
authors.lastname: Zeka
authors.forename: David
authors.initials: D
authors.lastname: Kriebel
authors.forename: Susan M
authors.initials: SM
authors.lastname: Kennedy
authors.forename: David H
authors.initials: DH
authors.lastname: Wegman
mesh_terms: D000328:Adult; D000367:Age Factors; D001336:Automobiles; D015331:Cohort Studies; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007219:Industrial Oils / Q000009:adverse effects*; D007221:Industry; D016015:Logistic Models; D008173:Lung Diseases, Obstructive / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology; D008297:Male; D008669:Metallurgy; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D012907:Smoking / Q000453:epidemiology; D013147:Spirometry; D014481:United States / Q000453:epidemiology