E-cigarettes emit very high formaldehyde levels only in conditions that are aversive to users: a replication study under verified realistic use conditions

Introduction:
This text discusses a replication study that aimed to investigate the levels of formaldehyde emissions from electronic cigarettes (e-cigarettes) under realistic use conditions. The study was conducted in response to a previous study that reported high levels of formaldehyde emissions from an old-generation e-cigarette, which received widespread media attention. The current study aimed to verify whether these high levels of formaldehyde emissions were due to unrealistic use conditions that create an unpleasant taste known as dry puffs.

Key Points:

* The study used the same e-cigarette equipment and liquid as the previous study and recruited experienced e-cigarette users to take 4-second puffs at different voltage settings.
* Dry puffs, which are characterized by an unpleasant burning taste, were detected at 4.2 V by 88% of participants, and the upper limit of realistic use was defined as 4.0 V.
* The levels of formaldehyde emissions ranged from 3.4 (SE= 2.2) µg/10 puffs at 3.3 V to 718.2 (SE= 58.2) µg/10 puffs at 5.0 V.
* The levels detected at 4.0 V were 19.8 (SE = 5.6) µg/10 puffs, which is 36-fold lower compared to the levels at 5.0 V.
* at 4.0 V, the daily exposure to formaldehyde from consuming 3 g of liquid with the device tested would be 32% lower compared to smoking 20 tobacco cigarettes.
* The study found that the high levels of formaldehyde emissions reported in the previous study were caused by unrealistic use conditions that create dry puffs, which are avoided by e-cigarette users.

Main Message:
The main message of this study is that it is crucial to verify that realistic use conditions are tested in laboratory studies of e-cigarette emissions. abuse of devices in the laboratory setting can result in misleading conclusions about the risk to consumers compared to smoking. The study emphasizes the importance of considering the behavior of e-cigarette users, such as avoiding dry puffs, when assessing emissions from e-cigarettes. The study also highlights the need for more consistent and reliable devices for research purposes and the importance of regulatory considerations for e-cigarette devices.

Farsalinos, Konstantinos E., Vassilis Voudris, alketa Spyrou, and Konstantinos Poulas. “E-Cigarettes Emit Very high Formaldehyde Levels Only in Conditions That are aversive to Users: a Replication Study under Verified Realistic Use Conditions.” Food and Chemical Toxicology 109 (November 2017): 90–94. https://doi.org/10.1016/j.fct.2017.08.044.