title: Estimating smokers' mouth-level exposure to select mainstream smoke constituents from discarded cigarette filter butts.
abstract: BACKGROUND
  Standardized machine smoking measurements are poor predictors of exposure. We have refined a method using the solanesol deposited in discarded cigarette butts as a marker for estimating deliveries of mainstream smoke constituents. Developing a fast and accurate method for measuring solanesol in cigarette filters to assess tobacco smoke intake could provide a way to assess how people smoke under natural conditions. We have developed and validated a new, lower-cost, high-throughput method to measure the solanesol content in discarded cigarette filter butts and correlated these measurements with mainstream smoke deliveries of nicotine and tobacco-specific nitrosamines (TSNAs).
  
  
  METHODS
  Cigarettes were machine smoked under a variety of conditions to cover a wide range of nicotine deliveries and solanesol levels in the spent cigarette filter. Following machine smoking, a 1-cm portion of filter material, measured from the mouth end, was removed from the cigarette butts for analysis. Although an isotopically labeled solanesol analog is currently not commercially available, we achieved excellent quantitative results using a structurally similar compound, geranylgeraniol, as an internal standard (IS). After spiking with IS and solvent extracted, solanesol extracts were then analyzed using liquid chromatography coupled with a single-quadrupole mass analyzer. Analysis was carried out using manual preparation as well as a high-throughput 48-well format using automated liquid handlers.
  
  
  RESULTS
  Recoveries of solanesol from cigarette butts exceeded 95% with excellent precision and exhibited excellent linearity for both preparation methods. In addition, we show that the mouth-level exposure for both nicotine and TSNAs may be estimated by their relation to the solanesol retained in the cigarette filter.
  
  
  CONCLUSIONS
  We believe that this method provides excellent versatility and throughput for the estimation of mouth-level exposure to a wide range of toxins in cigarette smoke under naturalistic conditions. In addition, this method allows a far more accurate measure of exposure both from a single cigarette as well as from daily smoking.
authors: Emergency Response and Air Toxicants Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, N.E., Mailstop F-55, Atlanta, GA 30341, USA. GPolzin@cdc.gov
authors: Gregory M
authors: GM
authors: Polzin
authors: Weijia
authors: W
authors: Wu
authors: Xizheng
authors: X
authors: Yan
authors: Joan M
authors: JM
authors: McCraw
authors: Shadeed
authors: S
authors: Abdul-Salaam
authors: Ameer D
authors: AD
authors: Tavakoli
authors: Liqin
authors: L
authors: Zhang
authors: David L
authors: DL
authors: Ashley
authors: Clifford H
authors: CH
authors: Watson
mesh_terms: D002273:Carcinogens / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods; D005374:Filtration / Q000295:instrumentation; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis*; D009055:Mouth; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013729:Terpenes / Q000032:analysis*; D014026:Nicotiana
chemical_list: D002273:Carcinogens; D013729:Terpenes; C017719:solanesol