Table 1.

Demographic data of coke-oven and non–coke-oven workers in a Chinese occupational population

VariablesNon–coke-oven workersCoke-oven workersP
n66141
Age (y, mean ± SD)38 ± 839 ± 70.43*
Sex (men/women, % of men)57/9 (86.4)128/13 (90.8)0.34
Current smokers (yes/no, %)24/42 (36.4)90/51 (63.8)<0.01
Cigarettes per day (mean ± SD)5.1 ± 7.78.3 ± 7.2<0.01
Alcohol user (yes/no, %)23/43 (34.8)60/81 (42.6)0.29
Coking history (y, mean ± SD)18.6 ± 6.9
BSM in air [μg/m3, median (range)]97.8 (2.6-149.1)328.6 (61.8-2,677.8)<0.01
Particulate-phase B(a)P in air [ng/m3, median (range)]49.1 (43.0-51.5)926.9 (250.7-3,723.1)<0.01
Urinary 1-OHP levels [μmol/mol creatinine, geometric mean (95% confidence interval)]0.7 (0.6-1.3)12.0 (10.4-13.9)<0.01§
  • * Student's t test for difference between coke-oven workers and non–coke-oven workers.

  • χ2 tests for differences in distributions between coke-oven workers and non–coke-oven workers.

  • Mann-Whitney U tests for differences between coke-oven workers and non–coke-oven workers.

  • § Student's t test for ln-transformed data between coke-oven workers and non–coke-oven workers.