Thermal decomposition of vitamin E acetate in a surrogate vaping environment

Significance of the Topic

Understanding thermal decomposition of inhaled products is critical for assessing health risks associated with vaping devices. Vitamin E acetate gained attention as a possible contributor to lung injury in vaping users, highlighting the need for precise analytical methods to characterize degradation products under realistic vaporization conditions.

Study Objectives and Overview

This study demonstrates a high-temperature headspace sampling approach as a surrogate for e-cigarette vaporization, aiming to identify thermal and oxidative degradation products of vitamin E acetate at temperatures typical of consumer devices (180–300 °C).

Applied Methodology and Instrumentation

Samples of vitamin E acetate (1–2 mg) were sealed in 20 mL headspace vials and incubated at defined temperatures in 30 °C increments for 5 minutes. The volatile and semi-volatile decomposition products released into the vial headspace were analyzed by gas chromatography–mass spectrometry. Full‐scan electron ionization spectra were matched against the NIST/EPA/NIH mass spectral libraries, and select identifications were confirmed using analytical standards. Data acquisition and processing were performed with dedicated chromatography software.

Used Instrumentation

• Thermo Scientific TriPlus 500 Headspace Autosampler
• Thermo Scientific TRACE 1300 Gas Chromatograph
• Thermo Scientific ISQ 7000 Single Quadrupole GC-MS
• TraceGOLD TG-35MS capillary GC column (30 m×0.25 mm×0.25 μm)
• Thermo Scientific Chromeleon Chromatography Data System

Main Results and Discussion

Significant thermal and oxidative decomposition of vitamin E acetate was observed starting at 240 °C, with identification of over 40 degradation products, including acids, aldehydes, ketones, and furanones. Key compounds such as formic acid, acetone, acetic acid, 2-butanone, and 2-hexanone were confirmed by standards and quantified below ingestion-based regulatory limits, though inhalation toxicity remains distinct. The headspace autosampler provided reproducible, tightly controlled temperature profiles that eliminated variability associated with direct vapor sampling.

Benefits and Practical Applications of the Method

• Provides a reproducible surrogate environment for vaporization studies
• Enables controlled assessment of thermal and oxidative degradation pathways
• Supports safety evaluation of e-liquid additives and regulatory decision-making
• Reduces variability linked to coil design, voltage, and cartridge condition in real devices

Future Trends and Potential Applications

The methodology can be extended to a wide range of e-juice components and other inhalation products. Future work may incorporate inert atmospheres to distinguish pure thermal degradation from oxidative pathways. Integration with quantitative workflows could inform exposure assessments and product formulation guidelines.

Conclusion

High-temperature headspace sampling coupled with GC-MS offers a robust, controlled platform for characterizing the decomposition products of vaping additives. This approach enhances our understanding of potential inhalation hazards and provides valuable data for manufacturers and regulators to improve consumer safety.

References

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