title: To what extent does adding tobacco to cannabis expose young users to nicotine?
abstract: BACKGROUND
  To determine if mulling, the process of adding tobacco to cannabis for its consumption, exposes young cannabis users to significant levels of nicotine.
  
  
  METHODS
  This observational study performed in 2009-2010 among Swiss youths aged 16-25 years involved the completion of a self-administrated questionnaire and the collection of a urine sample on the same day. Measures of urinary cotinine were blindly performed using liquid chromatography coupled-mass spectrometry. A total of 197 eligible participants were divided in 3 groups based on their consumption profile in the past 5 days: 70 abstainers (ABS) not having used cigarettes or cannabis, 57 cannabis users adding tobacco to the cannabis they smoke (MUL) but not having smoked cigarettes, and 70 cigarette smokers (CIG) not having smoked cannabis.
  
  
  RESULTS
  Exposure to nicotine was at its lowest among ABS with a mean (SE) cotinine level of 3.2 (1.4) ng/ml compared, respectively, with 214.6 (43.8) and 397.9 (57.4) for MUL and CIG (p < .001). While consumption profile appeared as the only significant factor of influence when examining nicotine exposure from the ABS and MUL participants on multivariate analysis, it did not result in substantial differences among MUL and CIG groups.
  
  
  CONCLUSIONS
  Urinary cotinine levels found among MUL are high enough to indicate a significant exposure to nicotine originating from the mulling process. In line with our results, health professionals should pay attention to mulling as it is likely to influence cannabis and cigarette use as well as the efficacy of cessation interventions.
authors.affiliation: Public Health Research Unit, CHUQ Medical Research Center, Quebec City, Canada;
authors.forename: Richard E
authors.initials: RE
authors.lastname: Bélanger
authors.forename: François
authors.initials: F
authors.lastname: Marclay
authors.forename: André
authors.initials: A
authors.lastname: Berchtold
authors.forename: Martial
authors.initials: M
authors.lastname: Saugy
authors.forename: Jacques
authors.initials: J
authors.lastname: Cornuz
authors.forename: Joan-Carles
authors.initials: JC
authors.lastname: Suris
mesh_terms: D000293:Adolescent; D000328:Adult; D003367:Cotinine / Q000652:urine; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000453:epidemiology*; D009538:Nicotine / Q000008:administration & dosage; D015995:Prevalence; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D013557:Switzerland / Q000453:epidemiology; D014029:Tobacco Use Disorder / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D009538:Nicotine; D003367:Cotinine