Table 2.

Summary of consumption data.

Parameter (units of measurement)	Power level and atomizer technology
	15 W using low-power atomizer	25 W using low-power atomizer	50 W using high-power atomizer
Mass of e-liquid consumed by EC during experiments (mg/puff)a	8.3	11.7	22.5
Mass of airborne e-liquid (mg/puff)b	7.9	11.6	13.3
E-liquid recovery rate (weight percent)c	95	99	59
Concentration of nicotine in the liquid particle phase (µg/puff)	88.5	130	230
Nicotine portioning in the particle phase (weight percent)d	62	64	NAe
Nicotine concentration in airborne dropletsf (mg/mL)	11.2	11.2	17.3

The recovery rate was calculated according to the e-liquid consumption that was used as a reference.

DLPI DEKATI low pressure impactor, EC electronic cigarette, µg micrograms, mg/mL milligrams per milliliter.

^aTank mass measurement.

^bDLPI stage mass measurement.

^cRatio of e-liquid collected in the DLPI set-up compared to the e-liquid loss by EC.

^dSum of the nicotine dosage for each DLPI stage using the mass of airborne e-liquid calculated in footnote b.

^eNA, Not applicable because the nicotine portioning in the particle phase for 50-W conditions cannot be rigorously estimated (using the calculation method described in footnote d) from the liquid collected in the DLPI because the recovery rate was too low to ensure that all the liquid collected by the DLPI was the entire liquid particle phase emitted by the EC.

^fNicotine in airborne droplets compared to the total nicotine mass emitted by the EC.