PT - JOURNAL ARTICLE AU - Soha Talih AU - Rola Salman AU - Rachel El-Hage AU - Ebrahim Karam AU - Nareg Karaoghlanian AU - Ahmad El-Hellani AU - Najat Saliba AU - Alan Shihadeh TI - Characteristics and toxicant emissions of JUUL electronic cigarettes AID - 10.1136/tobaccocontrol-2018-054616 DP - 2019 Nov 01 TA - Tobacco Control PG - 678--680 VI - 28 IP - 6 4099 - http://tobaccocontrol.bmj.com/content/28/6/678.short 4100 - http://tobaccocontrol.bmj.com/content/28/6/678.full SO - Tob Control2019 Nov 01; 28 AB - Introduction JUUL is an electronic cigarette (ECIG) with a compact form factor. It is prefilled with a liquid that is advertised to contain a high concentration of nicotine salt. JUUL commands 50% of the US ECIG market share, and its wide popularity with underage users has triggered unprecedented actions by the US FDA. Apart from its nicotine salt-containing liquid and compact form, a salient advertised design feature is a control circuit that limits the heating coil temperature, presumably reducing unwanted toxicants. In this study, several tobacco-flavoured JUUL devices were reverse engineered, and their aerosol emissions were studied.Methods Total nicotine and its partitioning (freebase and protonated), propylene glycol/vegetable glycerin (PG/VG) ratio, and carbonyls were quantified by gas chromatography (GC) and high performance liquid chromatography (HPLC). The temperature control functionality of JUUL was investigated using a temperature-controlled bath in which the coil was submerged.Results The liquid nicotine concentration was found to be 69 mg/mL, and the liquid and aerosol PG/VG ratio was found to be 30/70. In 15 puffs, JUUL emitted 2.05 (0.08) mg of nicotine, overwhelmingly in the protonated form. Carbonyl yields were significantly lower than those reported for combustible cigarettes, but similar to other closed-system ECIG devices. The heating coil resistance was 1.6 (0.66) Ohm, while the maximum power delivered by the JUUL device was 8.1 W. The control circuit limited the peak operating temperature to approximately 215C.Conclusions JUUL emits a high-nicotine concentration aerosol predominantly in the protonated form. JUUL’s nicotine-normalised formaldehyde and total aldehyde yields are lower than other previously studied ECIGs and combustible cigarettes.