title: Developing estimates of frequency and intensity of exposure to three types of metalworking fluids in a population-based case-control study of bladder cancer.
abstract: BACKGROUND
  A systematic, transparent, and data-driven approach was developed to estimate frequency and intensity of exposure to straight, soluble, and synthetic/semi-synthetic metalworking fluids (MWFs) within a case-control study of bladder cancer in New England.
  
  
  METHODS
  We assessed frequency using individual-level information from job-specific questionnaires wherever possible, then derived and applied job group-level patterns to likely exposed jobs with less information. Intensity estimates were calculated using a statistical model developed from measurements and determinants extracted from the published literature.
  
  
  RESULTS
  For jobs with probabilities of exposure≥0.5, median frequencies were 8-10 hr/week, depending on MWF type. Median intensities for these jobs were 2.5, 2.1, and 1.0 mg/m3 for soluble, straight, and synthetic/semi-synthetic MWFs, respectively.
  
  
  CONCLUSIONS
  Compared to case-by-case assessment, these data-driven decision rules are transparent and reproducible and may result in less biased estimates. These rules can also aid future exposure assessments of MWFs in population-based studies.
authors: Occupational and Environmental Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, DHHS, Rockville, Maryland.
authors: Melissa C
authors: MC
authors: Friesen
authors: Dong-Uk
authors: DU
authors: Park
authors: Joanne S
authors: JS
authors: Colt
authors: Dalsu
authors: D
authors: Baris
authors: Molly
authors: M
authors: Schwenn
authors: Margaret R
authors: MR
authors: Karagas
authors: Karla R
authors: KR
authors: Armenti
authors: Alison
authors: A
authors: Johnson
authors: Debra T
authors: DT
authors: Silverman
authors: Patricia A
authors: PA
authors: Stewart
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003661:Decision Support Techniques; D006801:Humans; D007219:Industrial Oils / Q000145:classification / Q000633:toxicity; D008153:Lubrication; D008297:Male; D008669:Metallurgy / Q000379:methods*; D008875:Middle Aged; D009511:New England; D016273:Occupational Exposure / Q000009:adverse effects / Q000032:analysis*; D011336:Probability; D011795:Surveys and Questionnaires; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced* / Q000453:epidemiology
keywords: bladder cancer; case-control study; exposure prediction model; metalworking fluids; retrospective exposure assessment