“Direct Dripping”: A High-Temperature, High-Formaldehyde Emission Electronic Cigarette Use Method

Electronic cigarettes (ECIGs) electrically heat and vaporize a liquid solution to produce an inhalable nicotine-containing aerosol. Normally the electrical heater is fed the liquid via an automatic wick system. Some ECIG users, however, elect to directly drip liquid onto an exposed heater coil, reportedly for greater vapor production and throat hit. Use of such "direct drip atomizers" (DDAs) may involve greater exposure to non-nicotine toxicants due to the potentially higher temperatures reached by the coil. In this study we examined nicotine and volatile aldehyde (VA) emissions from one type of DDA under various use scenarios, and measured heater temperature.