Chemical characterization of marijuana blunt smoke by non-targeted chemical analysis

Abstract

Background: Marijuana blunts, which are tobacco cigar wrappers filled with marijuana, are commonly smoked in the US as a means of cannabis use. The use of marijuana blunts presents toxicity concerns because the smoke contains both marijuana-related and tobacco-related chemicals. Thus, it is important to understand the chemical composition of mainstream smoke (MSS) from marijuana blunts. This study demonstrates the ability to detect and identify chemical constituents exclusively associated with blunt MSS in contrast to tobacco cigar MSS (designated as ‘new exposures’) through non-targeted chemical analysis.

Methods: Samples collected separately from blunt MSS and tobacco cigar MSS were analyzed using two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC-TOFMS).

Results and Discussion: Two new exposures, which likely represent only a subset of all new exposures, were identified by evaluating the data from thousands of detected signals and then confirming selected compound identities in analyses using authentic chemical standards. The two confirmed new exposures, mellein and 2-phenyl-2-oxazoline, are not cannabinoids and, to the best of our knowledge, have not been previously reported in association with cannabis, tobacco, or smoke of any kind. In addition, we detected and quantified three phenols (2-, 3-, and 4-ethylphenol) in blunt MSS. Given the toxicity of phenols, quantifying the levels of other phenols could be pursued in future research on blunt MSS.

Conclusion: This study shows the power and utility of GC × GC-TOFMS as a methodology for non-targeted chemical analysis to identify new chemical exposures in blunt MSS and to provide data to guide further investigations of blunt MSS.

Keywords:

• Marijuana blunt
• cannabis blunt
• blunt
• marijuana smoke
• cannabis smoke
• marijuana
• cannabis
• non-targeted chemical analysis
• two-dimensional gas chromatography–time-of-flight mass spectrometry
• GC × GC-TOFMS

Acknowledgments

The authors are grateful for the essential role of the NIDA Drug Supply Program in making this research possible. The authors thank Clint Fleshman of Battelle for his extensive work in conducting the machine-smoking sessions and collecting data for the test products. The authors thank Bartosz Koszowski of Battelle for preparing the blunts. The authors thank Carson Smith, Jennifer Potts, and John Kuczek of Battelle for their assistance in project coordination and management.

Disclosure of interest

Dr. Peters is currently employed by a licensed producer of cannabis based in Canada. Dr. Peters worked in conjunction with Dr. Klupinski (the Principal Investigator) on the study design and the consideration of new and distinctive exposure candidates while an employee at Battelle. She later contributed to writing this article while serving as an independent contractor to Battelle. No potential conflict of interest was reported by the other authors.

Additional information

Funding

This project was supported by Battelle’s independent research and development program.