title: Evaluation of urinary cyclohexanediols and cyclohexanol as biomarkers of occupational exposure to cyclohexane.
abstract: OBJECTIVE
  The aim of the present study was to comparatively evaluate the usefulness of urinary cyclohexanediols (CHdiols-U) and cyclohexanol (CHol-U) as biomarkers of occupational exposure to cyclohexane (CH).
  
  
  METHODS
  Sixteen subjects (14 men and 2 women) were exposed to CH during proof-printing work. Personal exposure monitoring was conducted during the whole shift on the last working day of the week. The time-weighted average level of exposure to CH (CH-A) was measured using a diffusive sampler. Two urine samples were collected from each worker at different times during the same week: a baseline urine sample (before the first shift of the working week, after a 5-day holiday with no CH exposure) and an end-of-shift urine sample (after the last shift of the same working week, the same day personal exposure monitoring was conducted). CH-A, CHdiols-U and CHol-U were determined using a gas chromatograph-flame ionization detector.
  
  
  RESULTS
  The CH-A concentrations ranged from 4.5 to 60.3 ppm, with a geometric mean (GM) of 18.1 ppm. The GMs and ranges (in parenthesis) of the creatinine (cr)-corrected end-of-shift 1,2-CHdiol-U, 1,4-CHdiol-U and CHol-U concentrations were 12.1 (4.1-36.6), 7.5 (2.4-20.1) and 0.4 (0.2-1.0) mg/g cr, respectively. Both CHdiols-U at the end of the shift were significantly correlated with CH-A (correlation coefficients for 1,2-CHdiol-U and 1,4-CHdiol-U of 0.852 and 0.847, respectively). No correlation was observed between CH-A and CHol-U.
  
  
  CONCLUSIONS
  CHdiols-U at the end of the last shift of the working week are suitable biomarkers of occupational exposure to CH, but CHol-U is not suitable.
authors.affiliation: Osaka Occupational Health Service Center, Japan Industrial Safety and Health Association.
authors.forename: Akito
authors.initials: A
authors.lastname: Takeuchi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Yoko
authors.initials: Y
authors.lastname: Endo
authors.forename: Toshio
authors.initials: T
authors.lastname: Kawai
authors.forename: Akira
authors.initials: A
authors.lastname: Namera
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamamuro
authors.forename: Kimiaki
authors.initials: K
authors.lastname: Sumino
authors.forename: Ginji
authors.initials: G
authors.lastname: Endo
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000652:urine; D003510:Cyclohexanes / Q000652:urine*; D003511:Cyclohexanols / Q000652:urine*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000032:analysis*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D003510:Cyclohexanes; D003511:Cyclohexanols; C506365:Cyclohexane