Carbonyl Emissions and heating Temperatures across 75 Nominally Identical Electronic Nicotine Delivery System Products: Do Manufacturing Variations Drive Pulmonary Toxicant Exposure?

Introduction:
This text is a summary of a scientific study examining the variability in carbonyl compound (CC) emissions from electronic nicotine delivery systems (ENDSs). The study aimed to determine whether this variability may be related to heating coil temperature variations stemming from manufacturing differences. By analyzing 75 nominally identical Subox ENDSs, the study provides insights into the relationship between heating coil temperature and CC emissions, as well as the impact of manufacturing variations on toxicant exposure.

Key Points:

* The study used 75 nominally identical Subox ENDSs powered at 30 W, with each tank fitted with a coil head from the same manufacturer.
* Researchers analyzed CC emissions, total particulate matter (TPM), and liquid composition under controlled puffing conditions.
* They found that ΔTmax (peak temperature rise) and CC emissions varied widely, with greater ΔTmax resulting in exponentially higher CC emissions.
* a small portion of atomizers accounted for most of the total formaldehyde emissions.
* Coil operating temperature rise during puffing was determined using the change in heating coil resistance and the temperature coefficient of resistance.
* The resistance logs from the puffing sessions revealed that coil temperature rise varied widely, affecting CC emissions significantly.
* Coils exhibiting above-average temperature rises in the original study also exhibited the same behavior several weeks later.

Main Message:
The study emphasizes the importance of considering ENDS product performance metrics alongside design-based regulations to effectively protect public health. The wide variability in CC emissions across nominally identical ENDS products suggests that manufacturing variations can significantly impact toxicant exposure. By implementing tighter manufacturing tolerances or temperature control algorithms, manufacturers could significantly reduce population-wide toxicant exposure. The findings reinforce the need for a comprehensive approach to regulating ENDS, considering both product design and performance to ensure public safety.

Talih S, Salman R, Karaoghlanian N, El-hellani a, Shihadeh a. Carbonyl Emissions and heating Temperatures across 75 Nominally Identical Electronic Nicotine Delivery System Products: Do Manufacturing Variations Drive Pulmonary Toxicant Exposure? Chemical research in toxicology. 2023;36(3):342-346. doi:10.1021/acs.chemrestox.2c00391