RAPID PROFILING OF VOCS AND SVOCS IN E-CIGARETTE VAPOURS FOR REGULATORY COMPLIANCE AND QUALITY CONTROL

Importance of the Topic

The analysis of volatile and semi-volatile organic compounds in e-cigarette vapour is critical for meeting evolving regulations and ensuring consistent product quality. Thermal desorption combined with gas chromatography–mass spectrometry (GC–MS) provides high sensitivity and selectivity for tracing nicotine, potential toxins and flavour agents generated during vaporisation.

Objectives and Study Overview

This study presents a streamlined protocol for sampling e-cigarette vapours onto sorbent tubes using a handheld grab sampler and for analysing target VOCs and SVOCs via an automated TD–GC–MS workflow. The goal is to enable rapid screening for regulatory compliance and quality control in the expanding vaping industry.

Methodology

Sampling was performed by connecting commercial e-cigarette devices to inert-coated sorbent tubes via the Easy-VOC grab sampler, collecting 50 mL vapour puffs representative of standard puff volumes. A calibration solution of key impurities was loaded onto tubes using a Calibration Solution Loading Rig. Two-stage thermal desorption pre-concentrated analytes into the GC–MS system for full automation of sample preparation, desorption, pre-concentration and injection.

Used Instrumentation

• Easy-VOC handheld grab sampler for volumetric vapour collection
• TD100-xr™ automated thermal desorber (Markes International)
• Agilent 7890B GC coupled to 5977A Quadrupole MS
• Inert-coated stainless steel Odour/Sulfur sorbent tubes (C3–C30)
• Calibration Solution Loading Rig (CSLR™)

Main Results and Discussion

Analysis of a matrix-matched standard confirmed clear separation of target impurities (diacetyl, acetylpropionyl, acetoin, diethylene glycol) from carrier matrices (propylene glycol, glycerin). Vapour sampling of tobacco-flavoured e-liquid detected trace-level acrolein and nicotine alongside flavour compounds (levomenthol, ethyl vanillin). A second study on menthol-blueberry liquid demonstrated the split-flow capability for quantifying high-loading glycols and low-level volatiles (monoterpenes such as α-pinene, sabinene, β-pinene) while preserving thermally labile species.

Benefits and Practical Applications

• Simplified, solvent-free sampling without extensive preparation
• Automated, high-throughput TD–GC–MS analysis for routine QC and compliance
• Flexible split-flow control to cover broad concentration ranges in a single run
• Potential extension to aroma profiling, competitor benchmarking and R&D in food and fragrance sectors

Future Trends and Opportunities

• Incorporation of heart-cut modulators to isolate high-loaded components and enhance trace analyte detection
• Coupling split flows to alternative detectors (e.g. FID) for targeted quantification
• Automation of multi-method analyses via re-collection features in next-generation TD-xr systems
• Expansion of analyte scope to address emerging compounds of concern and new regulatory lists

Conclusion

The integration of sorbent tube sampling, handheld grab sampling and automated TD–GC–MS offers a robust, sensitive and efficient workflow for e-cigarette vapour analysis. This approach supports regulatory compliance and quality assurance while providing avenues for future enhancements in sensitivity and methodological flexibility.

References

1. Tobacco Products Directive (2014/40/EU).
2. US FDA Deeming Rule (2016) and list of Harmful and Potentially Harmful Constituents.
3. V. Bansal and K.-H. Kim, Review on quantitation methods for hazardous pollutants released by e-cigarette smoking, Trends in Analytical Chemistry, 2016, 78: 120–133.
4. J.S. Herrington, C. Myers and A. Rigdon, Analysis of nicotine and impurities in electronic cigarette solutions and vapor, Restek Application Note, 2015.
5. T. Schripp, D. Markewitz, E. Uhde and T. Salthammer, Does e-cigarette consumption cause passive vaping?, Indoor Air, 2013, 23: 25–31.