A comparison of the electrical characteristics, liquid composition, and toxicant emissions of JUUL USA and JUUL UK e-cigarettes

Soha Talih,Najat Saliba,Rachel El-Hage,Ebrahim Karam,Alan Shihadeh,Sally Salam,Rola Salman,Nareg Karaoghlanian,Ahmad El-Hellani

doi:10.1038/s41598-020-64414-5

Soha Talih, Najat Saliba + Show 7 more

Open Access

https://doi.org/10.1038/s41598-020-64414-5

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Abstract

In 2018, JUUL entered the UK market, where EU regulations limit liquid nicotine concentration to 20 mg/mL, approximately one-third the level of JUUL products sold in the USA. We hypothesized that JUUL’s UK product was engineered to deliver greater electrical power and boost liquid vaporization such that the net nicotine delivery rate was similar to the US version. We compared electrical characteristics, liquid composition, and aerosol emissions of JUUL devices procured in the USA and the UK. Study outcomes included electrical power, total and freebase nicotine, propylene glycol/vegetable glycerin ratio, carbonyls, and reactive oxygen species. Liquids and aerosols were analyzed by GCMS, HPLC, and fluorescence. Compared to the US version, JUUL UK had approximately one-third the liquid nicotine concentration in the liquid (5.4 vs. 1.6 wt.%) and aerosol (4.7 and 1.3 wt.%). Other than nicotine concentration and yield, we found no differences in any other study outcome, including electrical power. Currently, JUUL UK emits nicotine at a far lower rate than the US product, offering an opportunity to study how this factor impacts user behavior, JUUL uptake, and other population-level outcomes across the two markets.

Highlights

Regulation of electronic cigarettes for public health ends is a growing challenge, as use by previous non-smokers, including children, has risen drastically[1,2,3]
We found that both devices utilized pulse-width modulation to deliver an average of approximately 1.1 V to the pod during puffing
JUUL devices sold in the UK were generally found to be the same in every measure as those sold in the USA except for nicotine liquid concentration and yield, which were approximately one-third those of the USA version

Summary

Introduction

Regulation of electronic cigarettes for public health ends is a growing challenge, as use by previous non-smokers, including children, has risen drastically[1,2,3]. Because the flux is approximately proportional to the product of electrical power and liquid concentration[5], a user of a low-nicotine concentration liquid can increase the power of a variable-power electronic cigarette to attain the same or greater nicotine levels as a user of a high nicotine concentration liquid with a lower power device. We hypothesized that JUUL Labs would increase the power output of its UK devices to compensate for the lower nicotine concentration allowed in that market. We analyzed and compared USA and UK versions of JUUL in terms of electrical power characteristics, liquid and aerosolized nicotine content, and emissions of carbonyl compounds (CCs) and reactive oxygen species (ROS).

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