Table 2

Demographic characteristics and confounding variables of biowaste collectors, compost workers, and control subjects

Group (n= )Age (y)Exposure (months)Workers with confounding exposuresSmoking habits
Mean (SD)(Range)Mean (SD)(Range)NeverFormerCurrent
Biowaste (53)33 (6)2-160 (21–50)18 (22)(2–126)5 9 935
Compost (58)40 (11)(19–59)37 (26)2-165 (4–112)7151033
Control (40)38 (11)(20–61) 0.4 (0.3)(0–1)710 426
  • 2-160 p<0.01 v both other groups with unpaired t test:

  • 2-165 p<0.001v biowaste collectors with unpairedt test.