Figure 3.

(A): Dry puff flavors of human assessment (dotted lines; these are the same data as shown in Figure 1) compared with the categorization based on laboratory analysis of dry puff markers (solid lines). Colors indicate flavor: menthol:blue, vanilla:orange, fruit:grey. At 25 W using the 1.2-ohm coil and the fruit-flavored e-liquid, one of the three laboratory measurements yielded unexpectedly low amounts of the dry hit markers, resulting in the unexpected “drop-off” of the graph from 22 W to 25 W. This was likely caused by a technical problem with the e-cigarette or vaping machine that occurred during this measurement, but the data were nevertheless retained because the reason is unknown. (B): Suitability of different power settings for each coil/liquid combination, as assessed by human e-cigarette users and based on the amounts of dry puff markers measured in the laboratory. For the “human assessment”, red indicates that 10% or more of the puffs for that liquid/coil/power setting combination were reported by the e-cigarette user panel to have dry puff flavor. For the “laboratory assessment”, red indicates that one or several dry puff markers exceeded its cutoff value (Table 1) for one or more of the three puffs analyzed.