Disposable e-cigarettes and cigarette butts alter the physiology of an aquatic plant Lemna minor (Lemnaceae)

<p dir="ltr">Cigarette butts are one of the most littered single-use plastic items worldwide and can have ecotoxicological effects. e-Cigarettes (or ‘vapes’) have gained popularity globally as an alternative to tobacco-based cigarettes in recent years. The increased availability of disposable e-cigarettes has resulted in a rise in their littering, presenting a complex form of e-waste in the environment, yet the environmental impacts of littered e-cigarettes are largely unknown. Here <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/lemna-minor" target="_blank"><i>Lemna minor</i></a> (common duckweed) was used as a model organism to understand the effects of smoked cigarettes, vaped e-cigarettes or e-liquid. Growth-related <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/physiological-response" target="_blank">physiological responses</a> were measured (biomass, root development and <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/frond" target="_blank">frond</a> chlorophyll content). After 14 days of exposure to cigarette butts there was an increase of all measured growth variables. On the contrary, exposure to e-cigarettes or e-liquid caused a decrease in root length, biomass and frond number relative to controls. The significant deviations from control conditions suggest that the presence of either cigarette butts, e-cigarettes or e-liquid caused stress to the model plant which could indicate disruption of <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/aquatic-ecosystem" target="_blank">aquatic ecosystems</a> at the primary producer level. Disposable vapes pose a novel threat to aquatic ecosystems and it would be prudent to prevent them from becoming the next top litter item.</p>