AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Accuracy of the Temperature Control Feature in Advanced Electronic Cigarettes
SEYED AHMAD REZA DIBAJI, Suvajyoti Guha, Bruce Murray, Matthew R. Myers, Aarthi Arab, Jenna F. Dumond, U.S. Food and Drug Administration, CDRH
Abstract Number: 226 Working Group: Health Related Aerosols
Abstract Electronic cigarettes, or electronic nicotine delivery systems (ENDS), are rapidly gaining popularity among tobacco products. ENDS electrically heat a wire coil, made of kanthal, stainless steel, nickel and other materials, and vaporize an e-liquid solution, containing propylene glycerol, vegetable glycerin, and nicotine, to produce an inhalable nicotine-containing aerosol. Compared to earlier devices, many products among the latest generation of ENDS are capable of delivering much higher power (up to 300 Watts) and have a temperature control feature enabling the user to pre-set the temperature of the coil to as high as 300 ˚C. At high temperatures (∼ 250 ˚C), e-liquid components have been shown to decompose, resulting in the generation of toxins and carcinogens such as acrolein and formaldehyde. Substantial knowledge gaps exist regarding temperature distribution within the heating coil, as well as the generated aerosol by the latest generation of ENDS. This knowledge is critical for managing the risk associated with ENDS use.
To the best of our knowledge, this is the first study to test the accuracy of the temperature control feature and investigate the temperature of the heating coils. Thermocouples were attached to the heating coil using thermally conductive cement, and temperature measurements were performed for three different brands of e-cigarettes. The measurements were made at different power levels and puffing flow rates. The heating coil temperatures were found to exceed the temperature set point, by up to 117 ˚C, in 4 out of the 12 devices tested. The recorded temperatures also revealed a substantial variation along the coil length, with the mid-coil temperature significantly exceeding the temperature at the endpoints (sometimes by 100 ˚C). The results provide insight into functionality of the temperature control feature provided in ENDS and, when correlated with known toxin production at different temperatures, will be useful in assessing the risk associated with ENDS.