Cannabinoids in Exhaled Breath following Controlled Administration of Smoked Cannabis

Abstract

BACKGROUND Δ9-Tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), and cannabinol (CBN) were measured in breath following controlled cannabis smoking to characterize the time course and window of detection of breath cannabinoids. METHODS Exhaled breath was collected from chronic (≥4 times per week) and occasional (<twice per week) smokers before and after smoking a 6.8% THC cigarette. Sample analysis included methanol extraction from breath pads, solid-phase extraction, and liquid chromatography–tandem mass spectrometry quantification. RESULTS THC was the major cannabinoid in breath; no sample contained THCCOOH and only 1 contained CBN. Among chronic smokers (n = 13), all breath samples were positive for THC at 0.89 h, 76.9% at 1.38 h, and 53.8% at 2.38 h, and only 1 sample was positive at 4.2 h after smoking. Among occasional smokers (n = 11), 90.9% of breath samples were THC-positive at 0.95 h and 63.6% at 1.49 h. One occasional smoker had no detectable THC. Analyte recovery from breath pads by methanolic extraction was 84.2%–97.4%. Limits of quantification were 50 pg/pad for THC and CBN and 100 pg/pad for THCCOOH. Solid-phase extraction efficiency was 46.6%–52.1% (THC) and 76.3%–83.8% (THCCOOH, CBN). Matrix effects were −34.6% to 12.3%. Cannabinoids fortified onto breath pads were stable (≤18.2% concentration change) for 8 h at room temperature and −20°C storage for 6 months. CONCLUSIONS Breath may offer an alternative matrix for testing for recent driving under the influence of cannabis, but is limited to a short detection window (0.5–2 h).

Potential of Mass Spectrometry in Developing Clinical Laboratory Biomarkers of Nonvolatiles in Exhaled Breath

“…There were significantly higher THC plasma concentrations in participants with THC detectable in breath. This supports the possibility that breath can be an alternative to blood to disclose very recent drug intake, which is relevant for example in drugged-driving monitoring (21 ).…”

“…THC was detected in exhaled breath for a few hours' time in all participants but 1 (21 ). In a previous study, samples were collected 1-2 h after smoking cannabis and all 8 participants were positive for THC (18 ).…”

Phosphatidylethanols in Breath: A Possible Noninvasive Screening Test for Heavy Alcohol Consumption

“…When mass spectrometric assays give unexpectedly low results, one should contemplate the possibility of the presence of variants and scan for them. One reason for doing this is that a "missed" pathogenic variant would give the clinically correct result for the wrong reason, which might result in a failed opportunity for definitive genetic family testing (4,5 ). The other reason is that several of the variants are either nonpathogenic or of uncertain significance, leading to a potentially falsely low IGF-1 result being reported.…”

“…Breath testing has also been successfully explored as an alternative method for drugs of abuse, since low molecular weight substances circulating in the body are to some extent exhaled in breath as part of aerosol particles (3 ). A variety of abused substances, including amphetamines, benzodiazepines, cannabis, cocaine, and opiates, are detectable in breath samples (4,5 ).…”

Exhaled Breath Analysis of Smokers Using CMV-GC/MS

“…The same procedures were used in the examination of the response of THC in a MeOH mixture for the following calibration points of 50, 100, 200, 300, 400, 500 ppb. The concentrations of THC examined in these experiments reflected a range that would be representative of the low levels that would be 0.E+00 expected in exhaled breath samples [55][56][57][58]. The six points gave a linear response for both liquid (R 2 =0.9865) and CMV (R 2 = 0.9798) employed methods as shown in Figure 9.…”