Table 1

Electrical characteristics, liquid composition and emissions for five different disposable e-cigarettes and one JUUL; average (SD)

TypePod-mod-like disposablesPod system
BrandEzzy OvalHydePuff BarSEAJUUL
FlavourBerry coolMango lycheeCherry lemonadeBanana iceMintClassic tobacco
Electrical
 Voltage (V)3.923.813.813.783.743.79
 Resistance (Ω)1.721.911.751.642.781.6
 Computed power (W)8.947.68.288.675.030.6-421*
Liquid composition
 Labelled nicotine (% weight)555555
 Labelled nicotine (mg/mL) 575761575859
 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 % protonated97 (3.5)97 (1.5)§99 (0)§99 (0)§98(1)§94.3 (1.5)
 pH4.95 (0.04)§5.21 (0.06)§4.81 (0.05)§5.08 (0.02)§4.77 (0.03)§6.14 (0.04)
 PG/VG51/49§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)
  Formaldehyde8.53 (3.22)§5.85 (0.6)§1.36 (0.09)§0.41 (0.03)0.95 (0.15)§0.32 (0.05)
  Acetaldehyde57.19 (27.73)24.72 (3.85)§5.47 (0.71)§4.28 (0.48)§4.56 (0.45)§1.77 (0.11)
  Acetone37.22 (6.16)§33.34 (1.48)§11.91 (0.24)23.65 (0.24)§9.61 (0.25)§11.86 (0.03)
  AcroleinNDNDNDNDNDND
  Propionaldehyde9.52 (5.55)2.6 (0.78)0.33 (0.16)0.28 (0.2)0.57 (0.12)ND
  Crotonaldehyde3.6 (0.55)§1.5 (0.39)§0.94 (0.17)§0.86 (0.07)§0.69 (0.09)§0.44 (0)
  Methacrolein4.8 (0.68)§3.97 (0.52)§1.25 (0.1)§3.28 (0.02)§1.02 (0.1)§1.65 (0.02)
  Butyraldehyde0.32 (0.56)NDNDNDNDND
  ValeraldehydeNDNDNDND0.21 (0.36)0.45 (0.78)
  Glyoxal0.72 (1.24)1.1 (0.95)0.75 (0.65)ND1.52 (0.15)§ND
  Methylglyoxal16.64 (0.56)§4.64 (2.5)13.37 (0.86)§3.79 (0.63)§8.16 (7.25)1.2 (0.01)
   Total carbonyls138.53 (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.