title: The urinary cotinine and serum 25 hydroxyvitamin D levels in male smokers.
abstract: OBJECTIVE
  To assess urinary cotinine and the effects of smoking on 25(OH)D levels in 67 male smokers.
  
  
  METHODS
  Urine and blood specimens were analyzed for cotinine and serum 25 hydroxyvitamin D (25(OH)D) concentrations by high performance liquid chromatography (HPLC) and chemiluminescent immunoassay, respectively. The accuracy, precision and detection limit of the HPLC method were also tested.
  
  
  RESULTS
  The detection limit of urinary cotinine was 0.02 microg/ml. The recoveries of cotinine concentrations of 0.15-2.0 microg/ml were greater than 95%. Only 23.9% of smokers had sufficient levels of serum 25(OH)D at least 30 ng/ml. The smokers were divided into dairy co-operative smokers and other smokers. The average urinary cotinine concentrations of 1,421.42 and 1,866.52 microg/g creatinine were not significant different in dairy co-operative smokers and other smokers whereas the average 25(OH)D of 29.09 and 22.65 ng/ml, respectively, were significantly different at p-value of < 0.001.
  
  
  CONCLUSIONS
  The 42.86% and 10.26% of the diary co-operative smokers and other smokers had sufficient serum 25(OH)D levels to prevent osteoporosis.
authors.affiliation: Department of Occupational Health and Safety, Faculty of Public Health, Mahidol University, Bangkok, Thailand.
authors.forename: Thanawan
authors.initials: T
authors.lastname: Buacharoen
authors.forename: Pornpimol
authors.initials: P
authors.lastname: Kongtip
authors.forename: Prapin
authors.initials: P
authors.lastname: Tharpoophasiam
authors.forename: Suttinun
authors.initials: S
authors.lastname: Chantanakul
authors.forename: Dusit
authors.initials: D
authors.lastname: Sujirarat
mesh_terms: D000328:Adult; D015992:Body Mass Index; D050071:Bone Density Conservation Agents / Q000097:blood*; D003367:Cotinine / Q000652:urine*; D003430:Cross-Sectional Studies; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood*; D008297:Male; D012907:Smoking / Q000378:metabolism*
chemical_list: D050071:Bone Density Conservation Agents; D006887:Hydroxycholecalciferols; D003367:Cotinine