"I get the flavors and it makes me love vaping more:" How and why youth users modify electronic nicotine delivery systems.

Youth from our study indicated that they make modifications to the ENDS devices, specifically to the e-liquid. These modifications are both intended by the manufacturer, such as changing the e-liquid and replacing coils, and unintended, such as adding substances not meant for vaping. Future policies aimed at reducing youth ENDS use should consider mandating better safeguards against modifications that appeal to youth.