Table 1.

Demographic characteristics of the subjects

Smokers of herbal cigarettesSmokers of regular cigarettesP
Sample size, n135143
Age (y), median (IQR)48 (38-56)48 (39-54)0.567*
Cigarettes per day on average
    Median (IQR)20 (15-20)20 (15-20)0.962*
Education, n (%)
    Junior high school and below70 (52)77 (54)
    Secondary technical school41 (30)42 (29)
    Junior college20 (15)18 (12)
    College and above4 (3)6 (4)0.621
Employment status, n (%)
    Employed81 (60)94 (66)
    Unemployed54 (40)49 (34)0.979
Monthly income (yuan), n (%)
    <50019 (14)30 (21)
    500-99940 (30)41 (29)
    1,000-1,99958 (43)52 (36)
    2,000-4,99917 (12)18 (12)
    ≥5,0001 (1)2 (1)0.567
Change in daily consumption after switching from regular cigarettes (14-15 mg) to herbal cigarettes, %
    Increased daily consumption47
    Decreased daily consumption30
    No change in daily consumption23
Cotinine and trans-3′-hydroxycotinine, median (IQR)
    Sample size134142
    Cotinine (μg/mg creatinine)12.8 (5.57-22.2)14.3 (8.00-23.7)0.169*
    Cotinine (ng/mL)1,142 (476-2,175)1,538 (666-2,463)0.047*
    trans-3′-Hydroxycotinine (μg/mg creatinine)33.0 (9.88-61.4)41.1 (15.6-65.7)0.146*
    trans-3′-Hydroxycotinine (ng/mL)2,799 (732-6,346)3,732 (1,518-7,230)0.058*
Total PAHs and total NNAL, median (IQR)
    Sample size4449
    Total PAHs (pmol/mg creatinine)172 (87.1-245)159 (126-225)0.554*
    Total NNAL (pmol/mg creatinine)0.454 (0.256-0.862)0.410 (0.291-0.649)0.171*
  • *Based on Mann-Whitney signed rank test.

  • Based on χ2 test.