title: Effects of smoking on trace metal levels in saliva.
abstract: OBJECTIVE
  To compare the salivary levels of trace metals between non-smokers and smokers using inductively coupled plasma mass spectroscopy (ICP-MS). The effect of pretreatment methods on the accuracy of ICP-MS analysis and daily variations in trace metal levels in saliva were also investigated.
  
  
  METHODS
  The participants were 10 male non-smokers (mean age: 27.4 ± 3.4 years) and 30 male smokers (mean age: 26.5 ± 4.1 years). Unstimulated whole saliva was collected. Salivary flow rate, the number of metal restorations in the oral cavity, the level of blood contamination in the saliva and the levels of cotinine and trace metals in the saliva of each participant were determined.
  
  
  RESULTS
  Direct dilution of saliva samples with nitric acid showed the most accurate ICP-MS results. Trace metal levels in saliva showed wide daily variations. They were not affected by the number of metal restorations. Trace metal concentrations of saliva samples without blood contamination were much lower than the previously reported values. Salivary levels of cotinine and aluminum were significantly increased in smokers.
  
  
  CONCLUSIONS
  Saliva can be a medium for trace metal analysis. Salivary levels of cotinine and aluminum can be useful markers to evaluate smoking status.
authors.affiliation: Department of Oral Medicine and Diagnosis, College of Dentistry and Research Institute of Oral Science, Gangneung-Wonju National University, Gangneung, Korea.
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Kim
authors.forename: Y-K
authors.initials: YK
authors.lastname: Kim
authors.forename: H-S
authors.initials: HS
authors.lastname: Kho
mesh_terms: D000328:Adult; D000535:Aluminum / Q000032:analysis; D001769:Blood; D002104:Cadmium / Q000032:analysis; D003300:Copper / Q000032:analysis; D003367:Cotinine / Q000032:analysis; D003722:Dental Alloys / Q000737:chemistry; D006801:Humans; D007854:Lead / Q000032:analysis; D008274:Magnesium; D008297:Male; D008345:Manganese / Q000032:analysis; D008872:Microwaves; D008982:Molybdenum / Q000032:analysis; D017942:Nitric Acid; D012413:Rubidium / Q000032:analysis; D012463:Saliva / Q000737:chemistry* / Q000378:metabolism; D012636:Secretory Rate / Q000502:physiology; D012907:Smoking / Q000378:metabolism*; D013054:Spectrophotometry, Atomic; D013324:Strontium / Q000032:analysis; D013793:Thallium / Q000032:analysis; D014131:Trace Elements / Q000032:analysis*; D015032:Zinc / Q000032:analysis
chemical_list: D003722:Dental Alloys; D014131:Trace Elements; D002104:Cadmium; D007854:Lead; D017942:Nitric Acid; D008345:Manganese; D003300:Copper; D008982:Molybdenum; D013793:Thallium; D000535:Aluminum; D008274:Magnesium; D015032:Zinc; D003367:Cotinine; D012413:Rubidium; D013324:Strontium