Measuring PM2.5, Ultrafine Particles, Nicotine Air and Wipe Samples Following the Use of Electronic Cigarettes

Introduction:
This text is a summary of a scientific study that investigates the potential exposure of the general public to ingredients in electronic cigarettes (e-cigarettes) through secondhand and thirdhand (residual nicotine and other chemicals left on a variety of indoor surfaces) exposure. The study measures the transfer of nicotine from device to air to nonusers in the room to thirdhand deposition under short-term exposure conditions that a member of the public might encounter in a public setting.

Key Points:

* The study measured fine particulate matter (PM2.5), ultrafine particulate matter (UF), and nicotine concentrations in the air, as well as the deposition of nicotine on surfaces in the study room.
* Three e-cigarette users were asked to use the products ad libitum for 2 hours in a room furnished with prewashed fabric materials and other accessories designed to realistically simulate a social encounter of a member of the US population.
* Six nonusers also co-occupied the exposure room during the assessment period.
* The study performed two exposure sessions 1 week apart, the first session used a disposable e-cigarette, and the second session used a tank e-cigarette.
* The masses of the e-cigarette products were measured before and following each exposure to determine the amount of e-cigarette solution used during the exposure, and the amount of nicotine consumed.
* The room had one sealed interior window and one door, air was delivered to the room from the ceiling with downward movement, and the ambient air exchange rate was recorded at approximately 5-7 feet from the air inlets.
* Air monitoring was done before, during, and after both 2-hour sessions, and wipe samples were taken before and following both 2-hour sessions to measure the deposition of nicotine on surfaces in the study room.

Main Message:
The study found that short-term e-cigarette use can produce elevated PM2.5, elevated UF, nicotine in the air, and accumulation of nicotine on surfaces and clothing. This could lead to secondhand inhalation of these particles and chemicals by bystanders, as well as dermal exposure to nicotine. The study also found significant differences in PM2.5 and ultrafine particles between disposable e-cigarettes and tank-style e-cigarettes, suggesting a difference in the exposure profiles of e-cigarette products. These findings highlight the need for further research on the potential health risks of e-cigarette use and secondhand exposure.

Melstrom, Paul, Bartosz Koszowski, Meridith Hill Thanner, Eunha Hoh, Brian King, Rebecca Bunnell, and Tim McAfee. “Measuring PM2.5, Ultrafine Particles, Nicotine Air and Wipe Samples Following the Use of Electronic Cigarettes.” Nicotine & Tobacco Research 19, no. 9 (September 2017): 1055–61. https://doi.org/10.1093/ntr/ntx058.