title: Exposure to metal-working fluids in the automobile industry and the risk of male germ cell tumours.
abstract: BACKGROUND
  In a previous analysis of a case-control study of testicular cancer nested in a cohort of automobile workers, we observed an increased risk for testicular cancer among workers who had ever been involved in occupational metal-cutting tasks. We investigated whether this risk increase was due to exposure to metal-working fluids (MWF).
  
  
  METHODS
  Occupational exposure to MWF was assessed in detail using a job-specific questionnaire for metal-cutting work. We calculated ORs and associated 95% CIs individually matched for age (±2 years) and adjusted for a history of cryptorchidism by conditional logistic regression.
  
  
  RESULTS
  The prevalence of exposure to MWF was 39.8% among cases and 40.1% among controls. For total germ cell tumours and seminomas we did not observe risk increases for metal-cutting tasks or occupational exposure to MWF (OR 0.95; 95% CI 0.69 to 1.32 and OR 0.88; 95% CI 0.58 to 1.35, respectively). However, dermal exposure to oil-based MWF was associated with an increased risk for non-seminomatous testicular cancer. Dermal exposure to oil-based MWF for more than 5000 h showed particularly high risk estimates (OR 4.72; 95% CI 1.48 to 15.09).
  
  
  CONCLUSIONS
  Long-term dermal exposure to oil-based MWF was a risk factor for the development of non-seminomatous testicular germ cell cancer. Possible measures to reduce exposure include the introduction of engineering control measures such as venting or enclosing of machines, and enforcing the use of personal protective equipment during metal cutting.
authors: Bremen Institute for Prevention Research and Social Medicine, Bremen, Germany. tbehren@gmx.net
authors: Thomas
authors: T
authors: Behrens
authors: Hermann
authors: H
authors: Pohlabeln
authors: Birte
authors: B
authors: Mester
authors: Ingo
authors: I
authors: Langner
authors: Nils
authors: N
authors: Schmeisser
authors: Wolfgang
authors: W
authors: Ahrens
mesh_terms: D001336:Automobiles; D016022:Case-Control Studies; D006801:Humans; D007221:Industry / Q000706:statistics & numerical data; D008297:Male; D008669:Metallurgy / Q000706:statistics & numerical data*; D009373:Neoplasms, Germ Cell and Embryonal / Q000139:chemically induced / Q000453:epidemiology; D009784:Occupational Diseases / Q000139:chemically induced / Q000453:epidemiology*; D016273:Occupational Exposure / Q000009:adverse effects / Q000706:statistics & numerical data*; D009821:Oils / Q000633:toxicity; D012307:Risk Factors; D018239:Seminoma / Q000139:chemically induced / Q000453:epidemiology*; D012867:Skin; D011795:Surveys and Questionnaires; D013736:Testicular Neoplasms / Q000139:chemically induced / Q000453:epidemiology*
chemical_list: D009821:Oils