Due to the growing fad of vaping, its unknown health effects, and the lack of FDA standardized regulation, electronic cigarettes are a public health concern. Considering the known negative effects of tobacco cigarettes on the cardiovascular system, this experiment studies the effects of e-cigarette liquids on the heart rate of Daphnia magna, a model organism which responds similarly to pharmacological agents as humans. In this experiment, 500 Daphnia were immersed for 10 minutes in e-cigarette liquids, including 3 flavored liquids (juicy peach, berry ecto, and chocolate doughnut) with no nicotine, 3 flavored liquids with 0.1%, 0.204%, and 0.408% nicotine content, and 3 flavorless liquids with 0.1%, 0.204%, and 0.408% nicotine content. The heart rates of Daphnia were then recorded via video microscopy. The berry ecto flavored e-cigarette liquids with and without nicotine were the only ones to significantly affect heart rate. Despite the addition of nicotine in one liquid, both berry flavored liquids slowed Daphnia heart rate by 50% or more. This observational study suggests that not all e-liquids are the same in their chemical composition or their physical affects and posits the need for further investigation into the mechanism of e-liquid flavoring. (Project funded by student research grant)

The Effects of Electronic Cigarette Liquids on the Heart Rate of Daphnia Magna