Electrical characteristics, liquid composition and emissions for five different disposable e-cigarettes and one JUUL; average (SD)
| Type | Pod-mod-like disposables | Pod system | ||||
| Brand | Ezzy Oval | Hyde | Puff Bar | SEA | JUUL | |
| Flavour | Berry cool | Mango lychee | Cherry lemonade | Banana ice | Mint | Classic tobacco |
| Electrical | ||||||
| Voltage (V) | 3.92 | 3.81 | 3.81 | 3.78 | 3.74 | 3.79 |
| Resistance (Ω) | 1.72 | 1.91 | 1.75 | 1.64 | 2.78 | 1.6 |
| Computed power (W) | 8.94 | 7.6 | 8.28 | 8.67 | 5.03 | 0.6-421* |
| Liquid composition | ||||||
| Labelled nicotine (% weight) | 5 | 5 | 5 | 5 | 5 | 5 |
| Labelled nicotine (mg/mL)† | 57 | 57 | 61 | 57 | 58 | 59 |
| Measured nicotine (mg/mL) | 53.8 (0.7)‡ | 75.4 (1.39)‡ | 86.9 (5.52)§‡ | 83.4 (2.12)‡ | 54.3 (0.82)‡ | 69.8 (7.69) |
| Estimated % protonated | 97 (3.5) | 97 (1.5)§ | 99 (0)§ | 99 (0)§ | 98(1)§ | 94.3 (1.5) |
| pH | 4.95 (0.04)§ | 5.21 (0.06)§ | 4.81 (0.05)§ | 5.08 (0.02)§ | 4.77 (0.03)§ | 6.14 (0.04) |
| PG/VG | 51/49§ | 49/51§ | 19/81§ | 50/50§ | 44/56§ | 35/65 |
| Emissions in 15 puffs | ||||||
| TPM (mg) | 108.8 (13.4)§ | 99.7 (10.4)§ | 65.1 (6.6)§ | 125.4 (4.6)§ | 45.6 (12.8) | 36.8 (1.9) |
| Nicotine (mg) | 4.07 (0.49)§ | 5.44 (0.49)§ | 3.15 (0.32)§ | 6.72 (0.31)§ | 1.67 (0.27) | 1.67 (0.14) |
| Carbonyls (µg) | ||||||
| Formaldehyde | 8.53 (3.22)§ | 5.85 (0.6)§ | 1.36 (0.09)§ | 0.41 (0.03) | 0.95 (0.15)§ | 0.32 (0.05) |
| Acetaldehyde | 57.19 (27.73) | 24.72 (3.85)§ | 5.47 (0.71)§ | 4.28 (0.48)§ | 4.56 (0.45)§ | 1.77 (0.11) |
| Acetone | 37.22 (6.16)§ | 33.34 (1.48)§ | 11.91 (0.24) | 23.65 (0.24)§ | 9.61 (0.25)§ | 11.86 (0.03) |
| Acrolein | ND | ND | ND | ND | ND | ND |
| Propionaldehyde | 9.52 (5.55) | 2.6 (0.78) | 0.33 (0.16) | 0.28 (0.2) | 0.57 (0.12) | ND |
| Crotonaldehyde | 3.6 (0.55)§ | 1.5 (0.39)§ | 0.94 (0.17)§ | 0.86 (0.07)§ | 0.69 (0.09)§ | 0.44 (0) |
| Methacrolein | 4.8 (0.68)§ | 3.97 (0.52)§ | 1.25 (0.1)§ | 3.28 (0.02)§ | 1.02 (0.1)§ | 1.65 (0.02) |
| Butyraldehyde | 0.32 (0.56) | ND | ND | ND | ND | ND |
| Valeraldehyde | ND | ND | ND | ND | 0.21 (0.36) | 0.45 (0.78) |
| Glyoxal | 0.72 (1.24) | 1.1 (0.95) | 0.75 (0.65) | ND | 1.52 (0.15)§ | ND |
| Methylglyoxal | 16.64 (0.56)§ | 4.64 (2.5) | 13.37 (0.86)§ | 3.79 (0.63)§ | 8.16 (7.25) | 1.2 (0.01) |
| Total carbonyls | 138.53 (45.64)§ | 77.74 (9.74)§ | 35.37 (2.17)§ | 36.55 (1.43)§ | 27.88 (7.98) | 17.69 (0.64) |
*JUUL power is computed by averaging instantaneous measurements of coil voltage during puffing.
†Nicotine concentrations (mg/mL) were calculated based on the labelled concentrations and densities of propylene glycol (PG) and vegetable glycerin (VG).
‡Indicates significant difference between the measured and labelled nicotine concentrations.
§Indicates significant difference from JUUL.
ND, not detected; TPM, total particulate matter.