Indoor Environment Group, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS70-108B, Berkeley, CA, 94720, United States; División Química de La Remediación Ambiental, CNEA-CONICET, Avenida Gral. Paz 1499, (1650) San Martín, Buenos Aires, Argentina.
Indoor Environment Group, Lawrence Berkeley National Laboratory, 1 Cyclotron Road MS70-108B, Berkeley, CA, 94720, United States.
Environ Res. 2021 Jun;197:111188. doi: 10.1016/j.envres.2021.111188. Epub 2021 Apr 21.
"Sub-ohm" atomizers with reduced resistance can deliver more power than conventional electronic cigarettes. Typical battery outputs are 100 W or more. These devices are particularly popular among young users, and can be a significant source of volatile carbonyls in the indoor environment. Emissions from next-generation sub-ohm vaping products were characterized by determining e-liquid consumption and volatile aldehydes emissions for several combinations of popular high-power configurations. Tests explored the effect of dilution air flow (air vent opening), puffing volume, and coil assembly configuration. The mass of liquid consumed per puff increased as the puff volume increased from 50 to 100 mL, then remained relatively constant for larger puff volumes up to 500 mL. This is likely due to mass transfer limitations at the wick and coil assembly, which reduced the vaporization rate at higher puff volumes. Carbonyl emission rates were systematically evaluated using a 0.15 Ω dual coil atomizer as a function of the puffing volume and dilution air flow, adjusted by setting the air vents to either 100% (fully open), 50%, 25%, or 0% (closed). The highest formaldehyde emissions were observed for the lowest puff volume (50 mL) when the vents were closed (48 ng mg), opened at 25% (39 ng mg) and at 50% (32 ng mg). By contrast, 50-mL puffs with 100% open vents, and puff volumes >100 mL for any vent aperture, generated formaldehyde yields of 20 ng mg or lower, suggesting that a significant cooling effect resulted in limited carbonyl formation. Considering the effect of the coil resistance when operated at a voltage of 3.8 V, the amount of liquid evaporated per puff decreased as the resistance increased, in the order of 0.15 Ω > 0.25 Ω > 0.6 Ω, consistent with decreasing aerosol temperatures measured at the mouthpiece. Three different configurations of 0.15 Ω coils (dual, quadruple and octuple) were evaluated, observing significant variability. No clear trend was found between carbonyl emission rates and coil resistance or configuration, with highest emissions corresponding to a 0.25 Ω dual coil atomizer. Carbonyl emission rates were compared with those determined using the same methodology for conventional e-cigarettes (lower power tank systems), observing overall lower yields for the sub-ohm devices.
“亚欧姆”雾化器的电阻降低，可提供比传统电子烟更高的功率。典型的电池输出功率为 100W 或更高。这些设备在年轻用户中特别受欢迎，并且可能是室内环境中挥发性羰基化合物的重要来源。通过确定几种流行的高功率配置的电子烟液消耗和挥发性醛排放，对下一代亚欧姆蒸气产品进行了表征。测试探讨了稀释空气流量（通风口开度）、抽吸体积和线圈组件配置对测试的影响。随着抽吸体积从 50 增加到 100mL，每次抽吸消耗的液体质量增加，然后对于更大的抽吸体积（高达 500mL）保持相对恒定。这可能是由于在棉芯和线圈组件处的传质限制，这降低了更高抽吸体积下的蒸发速率。使用 0.15Ω 双线圈雾化器，根据抽吸体积和稀释空气流量，通过将通风口设置为 100%（全开）、50%、25%或 0%（关闭），系统地评估了羰基化合物排放率。当通风口关闭（48ngmg）、通风口开度为 25%（39ngmg）和 50%（32ngmg）时，观察到最低抽吸体积（50mL）下的甲醛排放量最高。相比之下，100%打开通风口的 50mL 抽吸量，以及任何通风口孔径的抽吸体积＞100mL，甲醛产量为 20ngmg 或更低，表明冷却效果显著，导致羰基化合物形成有限。考虑到在 3.8V 电压下运行时线圈电阻的影响，随着电阻的增加，每次抽吸蒸发的液体量减少，顺序为 0.15Ω＞0.25Ω＞0.6Ω，与测量到的口腔温度一致。评估了三种不同的 0.15Ω 线圈（双、四和八）配置，观察到明显的变化。在羰基化合物排放率与线圈电阻或配置之间没有发现明显的趋势，最高排放对应于 0.25Ω 双线圈雾化器。使用相同的方法比较了羰基化合物排放率与传统电子烟（低功率罐系统），观察到亚欧姆设备的总体排放量较低。
