Selected results from a case-control study of lymphohaematopoietic malignancies and exposure to benzene in Canadian petroleum distribution workers (Schnatter et al 1996) 25
| Exposed cases (n) | OR (95% CI) | |
| Potential confounders: | ||
| Socioeconomic job type: | ||
| Managerial or professional | 4 | 1.00 |
| Clerk or technician | 4 | 0.34 (0.03 to 3.10) |
| Operator or driver | 6 | 0.41 (0.07 to 2.33) |
| Smoking status: | ||
| Never | 0 | 1.00 |
| Ever | 7 | ∞ |
| Family cancer: | ||
| No | 8 | 1.00 |
| Yes | 5 | 2.51 (0.51 to 13.3) |
| Chest x ray film (n): | ||
| 0–9 | 7 | 1.00 |
| 10–14 | 3 | 1.41 (0.18 to 11.2) |
| 15–19 | 2 | 0.75 (0.01 to 18.8) |
| ⩾20 | 1 | 1.73 (0.02 to 156) |
| Cumulative exposure: | ||
| Benzene (by quartiles): | ||
| 0.0–0.17 | 2 | 1.00 |
| 0.18–0.49 | 8 | 5.06 (0.34 to 295) |
| 0.50–7.9 | 1 | 0.88 (0.01 to 18.2) |
| 8.0-219.8 | 3 | 2.11 (0.10 to 138) |
| Benzene (by tertiles): | ||
| 0.0–0.22 | 3 | 1.00 |
| 0.23–5.49 | 8 | 4.37 (0.72 to 48.6) |
| 5.50–219.8 | 3 | 0.92 (0.10 to 11.2) |
| Benzene (by median, 75th and 90th percentiles): | ||
| 0.0–0.49 | 10 | 1.00 |
| 0.50–7.99 | 1 | 0.22 (0.0 to 1.82) |
| 8.0–19.99 | 1 | 0.42 (0.01 to 3.95) |
| 20.0–219.8 | 2 | 0.96 (0.09 to 6.81) |
| Benzene (by regulatory standards): | ||
| 0.0–0.45 | 10 | 1.00 |
| >0.45–4.5 | 1 | 0.43 (0.01 to 4.05) |
| >4.5–45 | 1 | 0.16 (0.0 to 1.32) |
| >45 | 2 | 1.47 (0.16 to 13.1) |
| Benzene (by regulatory standards): | ||
| 0.0–0.90 | 10 | 1.00 |
| >0.90–9.9 | 2 | 0.43 (0.04 to 2.36) |
| >9.9–99.9 | 1 | 0.48 (0.01 to 4.55) |
| >99.9 | 1 | 1.03 (0.02 to 20.3) |