title: Non-smoker exposure to secondhand cannabis smoke II: Effect of room ventilation on the physiological, subjective, and behavioral/cognitive effects.
abstract: BACKGROUND
  Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects.
  
  
  METHODS
  Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for 1h. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/h. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures.
  
  
  RESULTS
  Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the digit symbol substitution task (DSST). One urine specimen tested positive at using a 50 ng/ml cut-off and several specimens were positive at 20 ng/ml. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results.
  
  
  CONCLUSIONS
  Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory.
authors.affiliation: Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA. Electronic address: eherrma3@jhu.edu.
authors.forename: Evan S
authors.initials: ES
authors.lastname: Herrmann
authors.affiliation: Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Cone
authors.affiliation: Research Triangle Institute, Research Triangle Park, NC 27709, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Mitchell
authors.affiliation: Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
authors.forename: George E
authors.initials: GE
authors.lastname: Bigelow
authors.affiliation: Substance Abuse and Mental Health Services Administration, Rockville, MD, USA.
authors.forename: Charles
authors.initials: C
authors.lastname: LoDico
authors.affiliation: Substance Abuse and Mental Health Services Administration, Rockville, MD, USA.
authors.forename: Ron
authors.initials: R
authors.lastname: Flegel
authors.affiliation: Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Vandrey
mesh_terms: D000293:Adolescent; D000328:Adult; D001288:Attention / Q000187:drug effects; D001519:Behavior / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002188:Cannabis / Q000009:adverse effects*; D003071:Cognition / Q000187:drug effects*; D013759:Dronabinol / Q000097:blood / Q000494:pharmacology; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005260:Female; D006213:Hallucinogens / Q000097:blood / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000523:psychology*; D008875:Middle Aged; D011597:Psychomotor Performance / Q000187:drug effects; D014691:Ventilation / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D006213:Hallucinogens; D013759:Dronabinol
keywords: Cannabis; Cognitive; Exposure; Marijuana; Secondhand; THC